TN C 2> >i»iin*it>ri«naiitw aoDM «** ww wnWMkW MW tf W H ^:-iiiiIFORNIA [Rull. 152 believed that a freneral averapfo of the ore wliich lias been piled up is 40 to 45 percent maiiiianeso. The V-shaped cut 200 feet west of the main cut encloses a caved tunnel, which was driven south into the ridge. About 5 tons of siliceous ore has been stacked by the side of this tunnel. The south end of the caved tunnel reveals blocks of black oxide ore, but no bedding is exposed. Blocks of ore are also exposed in the walls of the V-shaped cut to the west and to the east, but they occur only as loose blocks and not as a definite bed. They may roughly mark the course of a bed which occurs at depth below the regolith. The east limb on the V-shaped cut shows buff to greenish chert in beds 1 inch to 2 inches thick. The west limb of the cut is 6 feet deep but reveals only a regolith containing fragments of buff, green, and red chert. The ore in the V-shaped cut is more siliceous than that of the main cut, containing considerable amounts of white chert. It averages about 35 percent manganese. This bed must be different from that of the main cut, unless faulting occurs between them. Between the main cut and the V-shaped cut red chert is exposed. About 100 feet west of the V-shaped cut is sandstone, which evidently overlies the main chert body. Approximately 20 tons of ore have been piled up along the road 1 mile east of the mine. Also about 20 to 30 tons are stacked in the canyon just north of the mine. It is said that about 5 tons of ore have been trans- ported to Fruto for shipment. No. 9. Levensaler and Speir Prospect. (From files of U. R. (geo- logical Survey, 1918.) Records indicate that 62 tons of ore containing 42 percent manganese, 2 percent iron, and 17 percent silica, was produced in 1917 from the Levensaler and Speir properties near Fruto, probablv in T. 20 N., R. 6 W. No. 10. Battlesnake Mine. (By Ivan F. Wilson, July 16, 1942.) The Rattlesnake mine is south of Salt Creek in the SE^ sec. 6, T. 18 N,, R. 6 W. It is 2 miles southeast of the K. B. No. 4 claim (Glenn 8), at an altitude of 1,250 feet. It may be reached hj driving up the road toward the K. B. No. 4 claim for 2 miles, from where the workings at the Rattle- snake mine may be seen on a low hill half a mile to the southwest. The mine is located on the BroAvn and Moore Ranch of Stonyford. It is not being operated at present. The development includes a shaft 7 by 7 feet. At present the bottom is 14 feet deep, but it is caved and may have been considerably deeper. According to Bulletin 76,^ it was 20 feet deep. A drift apparently runs northwest from the shaft for a short distance. A cut 3 to 6 feet deep and 15 feet wide extends for 40 feet southeast of the shaft. Two other cuts, made with a bulldozer, are north and west of the shaft. Neither of these cuts exposes manganese ore. Some 75 tons was shipped in 1918. The manganese ore occurs in a massive, yellow-brown quartzose chert. This is the same type of rock as that at the K. B. No. 1 claim (Glenn 7) , and is described more fully in the report on that deposit. The ore may also contain bementite. Much of it is covered with a film of black oxide, except where freshly broken. The massive chert is 20 feet thick in the vicinity of the shaft. The black oxide ore occurs in pockets and irregular masses within the massive chert, and in many places is intermingled with 1 California Min. Bur. Bull. 76, p. 32, 1918. 1950] DESCRIPTION OF DEPOSITS 63 chert. No large mass of ore is exposed now, altliovigh there is some along the walls of the shaft, especially the northwest wall. Bulletin 76 states that the ore body was 4 to 6 feet wide. Most of the ore occurs near the top (southwest side) of the massive chert body. Some of the ore is hard blue-black psilomelane, but some includes pyrolusite. A few pieces of ore were seen which might run 50 percent manganese, but most of the mate- rial now exposed contains yellow-brown chert which would lower the grade considerably. Overlying the massive chert and manganese ore to the southwest is 10 feet of thin-bedded green chert, mixed with white and red chert. The chert occurs in beds 0.5 to 1 inch thick with shale partings. A shear zone is between this green chert and the ore body. Southwest of the thin-bedded green chert is a thick-bedded to massive white chert, without shale part- ings. It occurs in a belt 10 to 15 feet thick, and is overlain to the south- west by sandstone and shale. No exposures were seen northeast of the massive chert and manganese ore. The massive chert and manganese ore, thin-bedded green chert, and thick-bedded white chert occur in belts running roughly N. 60° W. The attitude at the shaft is nearly vertical, but along the strike in both direc- tions the beds dip to the southwest, indicating that this is the top side. A white chert bed to the southeast strikes N. 60° W., and dips 65° SW. The ore body appears to be cut off to the north by a fault treading N. 80° W. A cut run in this direction 15 feet north of the shaft reveals sandstone and shale, highly sheared in part. The chert beds and man- ganese ore strike into this sandstone and shale. The extent of the massive chert and manganese ore toward the southeast is uncertain, but it is exposed for a total length of 50 feet. It seems possible that most of the ore available on this property has been removed. Only 5 or 10 tons of ore is in sight. The situation at depth cannot be determined, as the shaft is partly caved, and it is unknown whether the ore was removed down to the limit of the oxide zone, or whether some may still remain. The main possibility for future develop- ment would probably be in reopening the shaft. HUMBOLDT COUNTY No. 1. A.B.C. Manganese Claim. (From files of U. S. Geological Survey, 1918.) The A.B.C. claim is 11 miles north-northwest of Blocks- burg on the trail to the Woods mine. It is N. 67° W. of Lasseck's Peak, in the NE^ T. 1 S., E. 4 E. The claim was located by Mrs. Dave Murphy of Blocksburg. The ore is found in a narrow irregular layer in thin- bedded chert. It is very siliceous, the best ore containing 35 to 40 percent silica. No development work had been done. This prospect is of little eco- nomic importance because of the high silica content and the distance from the railroad. No. 2. Burns Prospect. (From files of U. S. Geological Survey, 1918.) The Burns prospect is 6 miles north-northwest of Blocksburg and 1 mile northwest of the Blocksburg-Bridgeville road. It is on deeded land belonging to Mr. C. W. Manning and is in the southwestern part of T. 1 S., R. 5 E. It was discovered by Mr. Burns of Blocksburg. The pros- pect is on a flat west of, and above, Basin Creek, a tributary of Larabee Creek. It is 0.5 mile from a branch road which joins the main road 5 miles northwest of Blocksburg, 64 MANGANESE IK CALIFORNIA [Bull. 152 Because of the heavy covering of soil and the lack of development, no ore is seen in place and little is known as to the extent of ore. Over an area 250 feet in diameter, nothing but float of manganese ore and manganese stained chert could be found. The soil is full of small frag- ments of soft black manganese ore of good quality. Several large blocks of ore and manganese-bearing chert were found. As the slope is gentle, the blocks could not have come far. Along the east side of the flat, ser- pentine float is found. This float trends northward and seems to be the surface expression of a dike. No. 3. Charles Mountain (Woods, Hall) Mine. (By Frank S, Simons, July 5, 1942.) The Charles Mountain mine, sometimes known as the Woods or Hall mine, is in sees. 2 and 11, T. 1 S., R. 4 E., on the top of the ridge between Larabee Creek and the south fork of the Van Duzen River. It is 5.1 miles by a very steep and rough road from the Alderpoint- Blocksburg-Bridgeville road, and 26 miles from the shipping point, Alderpoint, on the NorthAvestern Pacific Railroad. The mine is on land owned by L. Windbigler, and is operated by F. M. Doak, James Warren, and Joseph Warren of San Francisco. Mr. Joseph Warren is supervising the mining at present. Five men are employed. A permanent camp has been established 0.3 mile from the mine, and an ample supply of water is at a spring 200 feet from the camp. The operators plan to work the property throughout the year, weather permitting. The production of the mine through 1920 is 742 tons. The ridge on which the mine is located is composed largely of thin- bedded red and brown chert in the northeast part of the area. The geologic relations of the ore body are shown in plate 1. The chert is faulted against sandstone along a zone trending northeast across the northwest corner of the mine area. Within the chert the structure is complex. There are probably many small faults which cannot be mapped. The east slope of the ridge is essentially a dip slope, although numerous small folds and wrinkles give a great variety of attitudes. Several open cuts are on the east slope of the ridge, all of which appear to have produced some ore, but in only one cut is ore now exposed. The relations of the different cuts to one another are not clear, as outcrops are scarce and attitudes are variable. The rocks have been faulted on a small scale, and this, together with the evident folding, has produced an apparently almost haphazard arrangement of ore outcrops. The amount of ore to be expected here cannot be estimated with the present available information. Tlie ore on the dumps along the east slope is siliceous, consisting of black oxides of manganese with cores of silica. All of the dumps, however, contain a little carbonate ore, and a few have small amounts of neotocite or bcmentite ore. The mineral probably is neotocite, as the ore is hard, brown, and apparently amorphous and opaline. None of the cuts appears to be more than 10 or 15 feet deep, so carbonate ore is found here at a rather shallow depth. Perhaps 50 tons of ore can be collected from the various dumps, carrying probably 30 to 35 percent manganese. The old workings on the north side of the hill consisted of three tun- nels and a winze along an ore bed, which presumably is a folded or faulted continuation of the ore bodj- on the east slope. The winze below the lowest tunnel is said to have been in ore all the way down to the 4th level, 50 feet below the 3d level. 1950] DESCRIPTION OF DEPOSITS 65 Most of the ore on the dump on the north side of the hill is banded gray manganese carbonate, containing probably 40 to 45 percent manga- nese. There is also a sugarj'-brown ore in small quantities, and a little low-grade oxide ore with leached white silica cores. Probabl}^ the ore to be found with further exploration will be carbonate ore, which occurs at shallow depths throughout the Charles Mountain area. Work at present is at the portal of level No. 3, which is being opened. Considerable trouble is encountered, as apparenth' the stope above level 3 has caved, allowing the dump from level 2 to sift down through the cave-in. More than 300 cars of muck have been removed so far, and the end is not in sight. As none of the old tunnels is accessible now, the under- ground conditions are not known. Probabl}' a considerable amount of ore remains below tunnel 3, as the old map gave no indication that any ore below that level had been removed. There were 4 feet of ore in the No. 4 level, which indicates that the ore ma}' persist at some depth below level 4. Extent along strike at anj' of the levels is, however, unknown. Inasmuch as accurate information on any part of the mine is lack- ing, an estimate of possibilities of the mine would be somewhat premature, and such estimate will have to be withheld pending the successful open- ing of the No. 3 level. However, it appears to the writer that core drilling might help to find ore in the area. No. 4. Fort Baker (Porter Ranch) Mine. (By Frank S. Simons and Max D. Crittenden, Jr., July 1942.) The Fort Baker mine, also known as the Porter Ranch mine, is in sec. 32, T. 3 N., R. 4 E., on the north side of Indian Creek. It is 15 miles by road from Bridgeville and 35 miles from Carlotta, the nearest rail point. The road is fair from the mine to Bridge- ville ; good from Bridgeville to Carlotta. The mine is on land owned by the Russ Company, and was idle at the time visited. The mine was operated by F. M. Doak in 1918, and 473 tons of ore averaging 47 percent manganese and 13 percent silica, was shipped. It was worked until 1920, when it was abandoned. The total production was 654 tons. The mine is on a small low knob, conspicuous because of the almost total lack of vegetation other than grass. The geologic relations are shown in plate 2. The rocks are sandstone and chert of the Franciscan group, with two small areas of greenstone on the east side of the ore body. The sandstone in several places appears to grade without perceptible break through a fine-grained siltstone and mudstone into thin-bedded chert, both laterally" and vertically through the section. The critical areas are without outcrops, so these gradational contacts are shown by dotted lines. The sandstone is a soft brown feldspathic rock, which crops out at oiil}' one place in the area mapped, and its presence in the area mapped is inferred from the predominance of sandstone tioat. The chert is gen- erally red, thin-bedded, with partings of shale, and is the rock which encloses the ore bodies. Nearly eveiy outcrop of chert carries thin films of black manganese oxide. The main chert body appears to be folded into an anticline pitching gently northeast and faulted along the southeast limb. In the ore zone the fault splits, and the rock between the two branches is a much sheared reddish slate with abundant fault gouge and breccia. The main ore bodies appear to have been in this brecciated zone, enclosed in red shale. 3 — 11208 66 MANGANESE IN CALIFORNIA [Bull. 152 < LxJ T' CO o Z o Q. z :s U- < (T < 2 O o ? o C3 Q a: >- (S> O _J z Z) o fr < 1- o o o LxJ o 1x1 UJ 0) 1- D H o o: o o CO U- 5 X 1950] DESCRIPTION OF DEPOSITS 67 The attitude of the fault is not known, but tlie northwest side has been upthrown or has moved northeast relative to the southeast side. Little ore was in sight in 1942. All the old workings are caved and the cuts are partly filled with debris. Apparently there were at least two ore bodies, the largest in the long open cut at the east side of the area, and a smaller one about 60 feet west. According to E. F. Davis and A. O. Woodford, who examined the mine in 1918, three ore bodies were exposed in the east workings. All the ore seen on various dumps and stock piles will carry at least 30 percent manganese, and scattered around the propert}^ are small amounts of ore that contain perhaps 45 to 50 percent manganese. The high-grade ore is hard, blue-black psilomelane, which evidently lies in thin seams in the red shale. The small amount of ore exposed in the present workings is a rather siliceous oxide, probably corresponding to the border zone of Davis and Woodford. The complex structure of the rocks makes the discovery of new ore bodies difficult, but the chances for finding additional high-grade ore seem favorable. No. 5. Fort Seward Mine. (By E. F. Davis and A. 0. Woodford, August 27, 1918.) The Fort Seward mine is owned by the Humboldt Land and Development Company, and is operated by F. M. Doak of San Francisco under a lease. Wilson Wood of Harris, first located the manganese. The mine is in sec. 15, T. 3 S., R. 4 E. It is 6 miles by road to Fort Seward on the Northwestern Pacific Railroad. The roads are fair, the haul all down hill, and ore is transported by motor truck, 3 loads of 5 tons each per day being the the usual haul. The principal workings are near the top of a small knob on the side of the ridge west of Fort Seward (fig. 1). They consist of two open cuts following an ore zone. The two open cuts come together at the top of the knob, at a place where the ore zone was offset by faulting. The northwest cut has been worked to a depth of 30 feet, the east cut to a depth of 15 feet. The larger part of the ore exposed in the open cut has been removed, but from the blocks still remaining it is clear that the ore lay in lenses parallel to the bedding of the enclosing radiolarian chert. The chert and the ore zone stand nearly vertical, though the dip varies slightly to one side or the other as the ore zone is traced along the surface, and in the deeper workings the dip is to the east. The central part of the ore zone is offset 10 feet by a fault. The ore zone varies in thickness from 5 to 20 feet. Locally, it contains lenses of massive chert and is underlain on the southwest by a body of chert 100 feet thick. Below this chert is sandstone. Above the ore zone on the northeast side is a belt of thin-bedded red radiolarian chert, 5 to 15 feet thick, which in turn is overlain by a medium-coarse-grained sandstone. A body of greenstone is within this sandstone, but it does not persist in a direction parallel to the general bedding and it seems to be an intrusive body. The ore body varies considerably. Near the surface, the ore consists of black oxides with varying amounts of intermixed silica. The greater part of the black oxide ore is hard and of very compact texture. Only a small amount of soft ore is present. One specimen typical of such ore gave the following assay: manganese, 55.0 percent; silica, 14.2 percent; iron, 0.9 percent; available oxygen 3.01 percent. The oxide ore varies in its silica content. Hand sorting is necessary. The amount sorted per man averages 0.5 ton a day. The primary ores appear in the deeper part of the workings and in cores in blocks of ore near the surface. For the most part the primary 68 MANGANESE IN CALIFORNIA [Bllll. 152 niatorinl consists of a brown, yollow-brown or cj-oain-oolorotl manganese (.-arbonate and a brown ore consistin''' of an intimate mixture of silica and manjjanese oxide in a lower form of oxidation than is present in the black oxides. This ore material has a resinous luster and is spoken of as "rosin jasper." A sample of somewhat siliceous brown carbonate ore jrave manganese, 2^3. 9 percent; insoluble, 20.0 percent; iron, 0.5 percent; available oxygen, O.OI) j)ercent ; carbon, 22.5 percent. These primary ores are cut by scattered veins of pink rhodochrosite or more rarely by veins of a lavender-pink hydrous manganese silicate. Numerous transitions from brown carbonate or brown ore to black oxide may be seen along joint cracks or bounding surfaces of the ore body. Operations began at this mine on November 1, 1917. In 10 months 450 tons of ore had been shipped to the Noble Electric Steel Company. The car shipments varied between 15 and 20 percent silica. One ear averaged 2)5 percent silica and one car was rejected because of high silica. In addition to the ore shii)ped, 275 tons of second-grade siliceous ore are piled on the property. This ore consi.sts of black oxide, which is separated from the shipping ore in sorting, and also it includes a considerable proportion of unoxidized brown carbonate and brown ore that was too siliceous to ship. A general sample gave manganese, 34.4 percent ; insolu- ble, 37.8 percent; iron, 1.3 percent. Six hundred feet S. 50° E. of the open cuts on top of tlie knob, an irregular open cut exposes ore. It may be that the ore here is a con- tinuation of the ore zone farther up the hill. This is not certain, however. There is some faulting, the effects of which are visible in the lower cut; furthermore, the strike of the chert beds between the two workings changes abruptly in places. About 40 tons of ore has been removed and only a very small amount of ore remains. Owing to the presence of several minor faults the relation of chert and ore is not certain. It is not possible to predict the future production of this working place. Fort Seward Mine. (Supplementary report by M. 1). Crittenden, August 1944.) The Fort Seward mine was Avorked by shallow open cuts during World AYar I, and a production of 450 tons is reported. It was leased to Mr. J. P. AVarren in 1943 (?), Avho has made the following production : Long tons Year (Nat.) Mn Fe SiO- H=0 1943 1,370 41.00 1.75 25.0 5 (est.) 1944 1,640 42.(X) 1.5 28.0 2.6 Total 3,010 41.6 The total production including the ore produced in World War I is 3,460 tons, averaging 42.3 percent manganese. The recent production has come from a bulldozer cut through the top of the knoll, and from two adits on the eastern slope. In August 1944, the upper adit had been driven 160 feet, and the ore stojied from there to the surface. A second adit was begun 35 feet lower, and the ore was being stoped between them. The ore bed was encountered in the lower adit, 56 feet from the portal, but a cross fault which displaced the ore to the north w-as not recognized, and the working was continued in the barren footwall for some distance (fig. 1). The ore zone was picked up again in a small crosscut 115 feet from the portal. The ore zone in the Fort Seward mine occurs near the top of a lens of chert, enclosed in sandstone of the Franciscan group. The genera] 1950] DESCRIPTION OP DEPOSITS 69 strike is N. 50° W., and the dip is steep to the northeast. The ore zone is reported to have been as mneh as 15 feet thick in the upper adit, but the average is probably 6 to 8 feet. Several steep cross faults which displaced the ore a few feet north on the v^^est side were exposed in tlie workings. The displacement was 5 to 6 feet on the two faults near the portal of the upper adit. The operator, however, has made no attempt *to locate the displaced segment of the ore west of the fault near the face of the upper adit. This block should be prospected by a crosscut northwest of the fault. The wall rocks above and below the ore are thin-bedded gray chert with more or less hematitic shale partings. Ten feet below the ore, massive red and yellow jasper, at least 10 feet thick, is exposed in the face of the lower adit. The ore itself occurs as a single massive bed of dense black material that was identified by means of its X-ray powder pattern as braunite mixed with silica. The only other mineral recognized is pink hydrothermal rhodochrosite, found in veinlets cutting the older braunite. A block of ore 4 feet thick, 30 feet high, and 180 feet long lying between the lower and upper adits was indicated by the exposures, in August 1944. Additional ore can be inferred to exist below this level and in the offset segment of the bed at the west end of the upper level. No. 6. Janes Creek Prospect. (By A. 0. Woodford, September 10, 1918.) William Dawkins of Eureka and associates have a mineral lease on 320 acres of land belonging to N. H. Falk of Areata. The lease includes the Janes Creek manganese prospect, tirst found by David Miner, a good seeker of Areata. The prospect is in sec. 21, T. 6 N., R. 1 E. It is 3 miles north of Areata and 0.5 mile from the Northwestern Pacific Rail- road on Janes Creek. The altitude of the prospect is 100 feet. The road to the railroad is in poor shape. Since September 1918, the small prospect hole has been enlarged to a cut extending 20 feet into the hill, at which point the cut is 15 feet deep. The average width is 5 feet, but the ore body pinches out within a short distance. Most of the exposures in the Areata district are of a soft buff sand- stone, presumably of late Tertiary age. At three places other hard rocks were observed. A street cut in Areata shows a feldspathic sandstone (Franciscan?) unconformably below the soft buff sandstone. Five miles north of Areata, on Warren Creek, a large knob of greenstone of the Franciscan group contains euhedral feldspars and is locally spotted with chlorite. Between these two exposures is the manganese deposit on Janes Creek. The ore body is an almost vertical bed in a decomposed feldspathic rock, probably a tuff. The ore is 12 to 18 inches wide. Parallel to the ore body, and 2 or 3 feet from it, is a zone of chert nodules. Shale is inter- bedded with the ore. The ore zone strikes N. 10° W., and dips 80° E. The ore is entirely black oxide and most of it breaks up very easily. Analysis of material submitted by the owners to Mr. Gallagher, a Eureka assayer, gave 51 percent manganese, and less than 1 percent silica. In the field the average grade of the ore body was estimated to be 40 per- cent manganese and 15 percent silica. A sample collected for analysis from various parts of the face, gave manganese, 41.5 percent ; iron, 5.5 percent ; silica, 8.1 percent. Some ore is hard and steely, and undoubtedly is high in manganese. The ore is jointed every few inches, and all joint planes are thickly coated with sticky yellow clay or ocher. Near the footwall are numerous thin partings of red shale, parallel to the wall. This shale is similar to 70 MANGANESE IN CALIFORNIA [Bull. 152 the thicker laminae of sliale in tlie country rocks near by, and to the shale seen elsewiiere in manganese deposits of the Franciscan jrroup. The small accessory- ore body on the footwall side of the main mass bounded on one side by chert, may be a faulted portion of the main body. In that case the interveninp: tuft' abruptly lenses out. The main ore body seems to be entirely enclosed in a decomposed feldspathic igneous rock, probably tuif. On the hanging-wall side this rock is massive and coarse- grained, and though easily broken with the hands, is good standing ground. It shows manganese films along joint planes. The footwall mate- rial is similar, but finer-grained. Neither wall of the ore body is sheared. The lenses of chert near the footwall are of a number of types. Some of them have probably been separated by shearing along the enclosing red shale. The surfaces of some nodules of chert are sliekensided, and a peculiar green clay or gouge is present in small amounts. The large lenses are greenish or brownish massive chert typical of the Franciscan group. Some of the smaller chert nodules are brilliant red, with white porous cores and manganese stains along fractures. Other brilliant red nodules are composed of porous bright red ocher. Still other nodules are hard, dense, and bright yellow, and some are heavy, brown, and submetallic, evidenth' containing considerable iron. The long axes of the ellipsoidal cherts are usually, but not always, roughly parallel to the walls of the ore body. No thin-bedded red chert with shale partings Avas found. No radiolaria could be seen with a hand lens. About 12 tons of ore was mined. No. 7. Leaning Tree No. 2 Claim. (By Frank S. Simons, July 30, 1942.) The Leaning Tree No. 2 claim is in the NEj sec. fl and the NWi sec. 10, T. 6 N., R. 4 E., on the ridge west of Ruby Creek, a tributary of Willow Creek. The claim notice is near Highway 299. The claim was located by Thomas 0. Millett, Mae Stinson, and Jess L. Millett on June 23, 1942, and trends 1,500 feet east from the discovery point. It is 7 miles w-est of Willow Creek and 40 miles east of Areata, the nearest railroad point. In this vicinity the cuts along Highway 299 expose quartzite and slate, which strike approximately east and dip south at different angles. These rocks are intruded by, or faulted against, hornblende diorite and greenstone. In a gouge zone in the greenstone the sheared material is thinly filmed with purplish manganese oxide. The zone is 3 feet thick and is exposed for 15 feet in the face of the road cut. No ore was found, and the best material seen probably carries less than 5 percent manganese. The prospect is of little value, and no development work has or should be done. No. 8. Live Oak Deposit. (By Parker D. Trask, April 8, 1942.) The Live Oak deposit is in the NW^ sec. 6, T. 4 S., R. 6 E., a few hundred feet west of the east border of Humboldt County, at an altitude of 3.000 feet. The deposit is on the Kohrbough ranch, and is under lease to Rae F. Helmke. It is reached by a crude bulldozed road 0.3 mile from the end of the existing road 8 miles from Alderpoint. The dejiosit lies in thin-bedded red chert adjacent to a large mass of greenstone in a countrv character- ized by landslides. The chert strikes N. 55° W., and dips 15° NE. The ore body consists of a thin lens of oxide 6 inches in thickness exposed in a cut for a distance of 6 feet. The grade is high, 45 percent manganese, but the quantity of ore is small, as the ore body is cut off by greenstone within a few feet of the present exposure. 1950] DESCRIPTION OF DEPOSITS 71 No. 9. Martin and Murphy Claim. (From files of U. S. Geological Survey, 1918.) Messrs. Charles Martin and Thomas Murphy of Blocks- burg have a manganese claim in T. 1 S., R. 5 E., about 2.5 miles east of the Charles Mountain mine (Humboldt 3). The ore body is said to be 18 inches wide. A sample of this ore showed a core of gray manganese car- bonate surrounded by a shell of oxide. No development has been done. No. 10. Mnrpluj Prospect. (From files of U. S. Geological Survey, 1918.) The Murphy prospect is 5.5 miles by road and trail northeast of Alderpoint, 0.3 mile from the Trinity County line. It is 0.5 mile south of the Alderpoint-Zeuia road, probably hi the W^ sec. 7, T. 3 S., R. 6 E. This prospect is on deeded land belonging to Mr. Jean and was discovered by Dave Murphy of Blocksburg. Siliceous manganese ore and manganese-stained chert crop out at several places along a north-northeast trending ridge north of Dobbin Creek. The best prospect occurs in thin-bedded crumpled and contorted red chert near the saddle where the telphone line crosses the ridge. Con- siderable float of siliceous ore is seen, and one small layer 4 inches wide was found in place. A few narrow veins of psilomelane cut the bedding of the chert. The ore consists of siliceous psilomelane and pyrolusite and seems to have been derived from a manganese carbonate and chert. The general strike of the rocks is N. 25° W., at right angles to the trend of the ridge. The dip is to the north. The chert is overlain by sandstone. About 80 to 90 yards up the ridge N. 25° E. from this outcrop is another belt of chert, 75 feet thick. This chert strikes N. 50° W., and dips 60° to 65° NE. Near the middle of this chert belt is a 6-ineh bed of siliceous manganese ore. The unaltered cores of chert are pink to red in color and are dotted with numerous dull white specks which seem to be manganese carbonate. This ore is too siliceous to be of economic importance. Several similar layers were seen within a radius of half at mile. No development has been done on any of these outcrops. The first out- crop mentioned is the only one of any promise and here only 20 tons of rather siliceous ore are in sight. Since the prospect is near a good road and only 5.5 miles from the railroad, prospecting would be justified but only on the outcrop first described. No. 11. Prior No. 1 Deposit. (By Parker D. Trask, April 9, 1942.) The Prior No. 1 deposit is on the Prior Ranch in the SWi sec. 25, T. 2 S., R. 5 E., at an altitude of 2,500 feet. The deposit is about 2 miles by trail from the end of a road and 8 miles from Fort Seward, the nearest rail point. It is under lease to Rae F. Helmke of Alderpoint. The ore body consists of a bed of oxide 1.5 to 2 feet in width and 20 feet long. It is in thin-bedded chert that extends up the hill for at least 600 feet. The ore body has not been outlined completely by present explor- ation, and may extend farther up the hill than current development indicates. The grade of the deposit is estimated to be 45 percent manga- nese. About 5 tons of 45 percent ore lies on a stock pile. No. 12. Bed Knoll Deposit. (From files of U. S. Geological Sur- vey, 1918.) A deposit called the Red Knoll, located near Fort Baker, is listed in the files of the U. S. Geological Survey. The operators are said to be J. M. McKnight, et al. No. 13. Sam Brown (World War No. 2) Prospect. (By Frank S. Simons, August 4, 1942.) The Sam Brown prospect is on the Hoopa Valley Indian Reservation, in sec. 15, T. 8 N., R. 4 E., on the north flank of 72 MANGANESE IN CALIFORNIA [BuU. 152 Seottisli Point. Tt is lield by 8ani Drown of Hoopa, anrl is named the World War Xo. 2 claim. Tt trends northwest 750 feet from the npper out- crop. The claim is .S miles by trail from a poor road, which leads 3 miles to Iloopa. Iloopa is 41 miles from Areata, the neai'est railroad point. No development has been done. A thick bed of qnartzite forms a low bridp:e. Interbedded Avith the quartzite is a bed of rhodonite ore averapin*; 6 feet in thickness and exposed for 40 feet alonjr the strike, which is approximately east. Coarse- ofrained <2:abbro crojis out 50 feet east of the east end of the ore bed, and the contact may be either intrnsive or a fanlt. It is not exposed at any place. The west end is buried, but 400 feet west of the last exposure is an outcrop of siliceous rhodonite ore 6 feet thick. There are no intervening exposures of ore, so this outcrop may be either a continuation of the upper ore bed or, more likely, a large piece of float. The rhodonite at the upper outcrop is a very fine-grained bright pink dense rock. Small amounts of pyrite, natiA'e copper, and malachite (?) are present. Some of the ore resembles siliceous brown ore found in the Mad River district in Trinity County (Trinity 20, 87, 44). Excluding the lower outcrop, 250 tons of rhodonite ore averaging 10 to 35 percent manganese is reasonably expectable. A small amount of oxide ore is also present, but probably not more than one ton, averaging 40 percent manganese. If two exposures are parts of the same ore body, a much larger tonnage is available. Any estimate of this tonnage would be highl}' conjectural, however. No. 14. Windbigler No. 1 Mine. (By Frank S. Simons, July 6, 1942.) The Windbigler No. 1 mine is in T. 1 S., K. 4 E., probably in sec. 15, on land owned by L. Windbigler of Bridgeville. The mine is on the west side of Charles Mountain, 1 mile from the road to the Charles Mountain Mine (Humboldt 3), and 24 miles from Alderpoint, the near- est railroad point. It is being operated by James and Joseph Warren of San Francisco. A series of landslide benches forms part of the west slope of Charles Mountain. At the edge of one of these benches, a ledge of sandstone strikes north, and along the east slide of this ledge numerous boulders and fragments of manganese ore have been found in an area 100 feet long and up to 25 feet wade. Prospecting has been carried on to a depth of 6 feet, entirely in landslide material and soil. The ore is fouiul as fragments ranging in weight from a few pounds to 600 pounds. Most of the ore is soft black manganese oxide, and gen- erally contains leached silica skeletons which make the ore rather porous. A few of the fragments have cores of gray laminated manganese carbon- ate, similar to the ore found at the Charles Mountain mine (Humboldt 3), and one fi-agment was oxidized to a depth of only 0.5 inch. The source of the ore has not been found, and, as several landslide benches are above the deposit, the source will be difficult, if not impossible, to find. The operators plan to prosjiect by stripping the surface with a bulldozer. No. 15. Windhif/lrr No. 2 Pi'o.'ipccf. (Bv Frank S. Simons. July 5, 1942.) The Wi)i(l])igler No. 2 prospect is in sec. 11, T. 1 S., R. 4 E., on patented land owned by Tj. AVindbigler of Bridgeville. It is 1 mile by trail from tlie road to the Charles Mountain mine (Humboldt 3), and 26 miles from Alderpoint, on the Northwestern Pacific Railroad. It is leased 1950] DESCRIPTION OF DEPOSITS 73 to James and Joseph Warren of San Francisco. The prospect lies on the north slope of Charles Mountain in a hnmmocky area that is probably part of a large landslide. The ore is found on a small knoll composed largely of brown and white Avell-bedded chert striking N. 45° W. and dipping 70° SW. The chert crops out for 100 feet along the strike. At the southeast end of the exposure of chert are numerous fragments of high-grade manganese oxide ore. The only ore in place consists of a few thing stringers in the chert. A mass of altered gabbro crops out 70 feet south of the chert, and 150 feet west is an exposure of sandstone. Sandstone also crops out 30 feet stratigraphically above the chert. Probably less than 10 tons of ore, averaging 45 to 50 percent manganese, will be found here. IMPERIAL COUNTY No. 1. Claim of Unknown Name North of Chocolate Drop Group. (By Ivan F. Wilson, March 12, 1943.) A claim of unknown name is 0.5 mile north of the Chocolate Drop group, on the west side of the road running south from Wiley Well. The deposit is probably in sec. 9, T. 9 S., R. 20 E. It is 32 miles by road from Bhi:he, the nearest shipping point. A few surface cuts have been developed. It is unlikely that there has been any production from the property. The deposit consists of manganese oxide, which forms a cement in sandstone and conglomerate. The host rocks are similar to the fan- glomerate wall rock of the Chocolate Drop deposit (Imperial 3). The manganese oxide may partly replace the matrix of the sandstone and conglomerate, but the individual grains and fragments appear to be coated by oxide, and not replaced to any great extent. The manganese oxide seems to follow certain layers of the sandstone, although in detail its distribution is irregular. The open cuts are on a dip slope of the manganese-bearing formation. The strike is northwest and the dip is about 15° NE. The manganiferous material is exposed over an area of 100 feet square. The thickness of the zone of material completely coated by oxide is 1 foot. An assay of a representative sample shows a manganese content of 12.07 percent. The deposit closely resembles the Orchard or Dunbar deposits near Lake Havasu (San Bernardino 16). The Orchard deposit is thought to have been derived from m.anganese oxide solutions spreading out into fanglomerate from fissures, and it is likely that this deposit may have formed in the same way. No definite fracture zones seem to cut the deposit, but numerous fissures are in the vicinity, as described in the report on the Chocolate Drop group (Imperial 3). Economic possibilities of this deposit are negligible, because of the low grade of the material. It is difficult to see how any form of mechanical concentration would be successful. The deposit is of about the same type and grade as the Orchard deposits, but is much smaller. Unless some use is found for the ore in the Orchard deposits, there is little reason to attempt to develop this deposit. No. 2. Anson Prospect. (From files of U. S. Geological Survey, 1918.) A deposit near Glamis is reported to have produced 72 tons of manganese containing 36 percent manganese, 1 percent iron, and 15 percent silica. The owner is given as W. J. Anson. 74 MANGANESE IN CALIFORNIA [Bull. 152 No. 3. Chocolate Drop (Big Bear, Black Jack, Black Queen, Ehonij) Group of Claims, {\^y Ivan F. Wilson, March 12, 1943.) The Chocolate Drop ••roup of chiims is at the west end of the Palo Verde Monntains in sec. 9, T. 9 !S., R. 20 E. It is reached by proceeding 17 niilos west of Blythe, then tnrning south for 15.5 miles. The mine is 6.5 miles south of Wiley Well, a total distance of 32.5 miles by road from ]>lyllie, the nearest shipping point. The claims are owned by 0. H. Tetzlart' of Banning, and were leased January 30, 1942, to the Mine Development Company, of which U.S. West of Los Angeles, is president. The group comprises four claims, called the Chocolate Drop, Black Queen, Black Jack, and ]iig Bear. The major development is on the Chocolate Drop claim, which has provided all the production known so far. The Ebony group is a old name for the deposits. The Black Queen claim Avas not seen. According to the report by Sampson and Tucker,^ the Chocolate Drop group in 1917 had a production of 300 tons of ore, which averaged 46 percent manganese, 2.2 percent iron, and 2 percent silica. During 1942 the present lessees shipped 30 tons of ore containing 42.18 percent manganese to the Metals Keserve stock pile at Phoenix, Arizona. The property was idle when visited, and it was understood that operations had been abandoned because of the difficulty of sorting ore of shipping grade. The Chocolate Drop group consists of fissure deposits of manganese oxide occurring in fanglomerate, and, in one place, in andesite. Several different fissures occur over an area half a mile wide. The fissures strike approximately north and are vertical or steeply dipping. Brecciated zones along the fissures are cemented with manganese oxide and the matrix is partly replaced by manganese oxide. Veinlets of manganese oxide and of later white calcite cut the fissure zones. The manganese oxide is mainly hard, black, botryoidal material of the psilomelane type. In places bands of this hard oxide alternate with bands of soft black crystalline oxide which is presumably pyrolusite, or possibly mauganite. Most of the fissure zones are of low grade, although in a few places the veinlets of manganese oxide are sufficiently concentrated to give a product containing about 40 percent manganese. The fanglomerate in which the fissures occur is orange to brown, coarsely stratified, and poorly sorted, containing subangular pebbles averaging 2 to 3 inches in diameter, but ranging up to 1 foot or 2 feet. The pebbles are mostly of andesite. There are interbeds of sandstone 2 to 3 feet thick. At the Chocolate Drop claim the fanglomerate strikes N. 35° W., and dips 10° NE. The nuijor development is along a fissure on the Chocolate Drop claim from which all production to date has been ol)tained, so far as known. Ore has been stoped on this fissure over a length of 95 feet, and followed by an oi)en cut to the north an additional 65 feet. The fissure continues farther north for several hundred feet, but is nearly barren over this distance. The fissure strikes N. 10°-20° W., and is vertical for the most part, or in places dips steeply to the west. At the face of the stope the ore zone is 2 feet thick at the roof, tapei'ing down to a thickness of 1 foot at the lloor. The ore body seems to have been 3 or 4 feet thick in the main part of the stope, but it pinches out at the bottom. > Samp.son, R. J., and Tucker, W. B., Mineral resources of Imperial County: Cali- fornia Div. Mines Rept. 38, p. 129, 1U42. 1950] DESCRIPTION OF DEPOSITS 75 The stope readies a maximum depth of 28 feet below the surface at the south end. The stope is open to the surface for the most part, but in two places pillars were left on the roof. Two small open cuts, 15 and 25 feet south of the shaft, reveal only barren fanglomerate ; however, it is possible that they are off the line of strike of the fissure. Parts of the stope wall are lines with botryoidal psilomelane, but this psilomelane does not extend far into the wall rock, except as narrow veinlets. A sample from the 2-foot zone of ore at the south face of the stope contains 41.15 percent manganese. The bottom of the stope is inclined upward to the north, running into an open cut 65 feet long and 5 to 6 feet deep in which the material was apparently too low in grade to provide shipping ore. The fissure con- tinues as a barren zone still farther north. A fault surface is well exposed in a cliff near the south end of this canyon. It has a smooth surface with prominent grooves pitching 15° N. The fault at this point strikes N. 15° W., and dips 75° W. It is followed by a layer of jasper 0.1 to 0.2 inch thick. Farther north the fault contains a psilomelane breccia 2 inches thick, consisting of fragments of psilomelane and wall rock cemented by soft black oxide. Still farther north the fault splits into two branches. An open cut along one of these branches has followed a psilomelane veinlet 2 to 4 inches thick. Other branching narrow veinlets occur in the vicinity. Another fissure lies 300 to 400 feet west of the main fissure. It is exposed by open cuts and trenches over a length of 75 feet. It strikes N. 5° E., and dips vertically. One open cut reveals a zone 5 feet wide contain- ing psilomelane type veinlets 1 inch to 4 inches thick. The proportion of wall rock is too great to make mining of this material feasible. Small veinlets of psilomelane are exposed 300 feet to the south along the same fissure. The Big Bear claim is 1,000 feet west and slightly south of the Chocolate Drop claim. Four open cuts have been developed along a fissure zone followed by narrow veinlets of psilomelane. At the north end a cut 15 feet long exposes 0.5 to 1 foot of breccia impregnated with manganese oxide. Psilomelane veinlets crop out on the surface to the north and south. Another open cut, 70 feet S. 10° E. from the first cut, is 20 feet long and 4 feet deep. It exposes psilomelane vein material, containing a few brec- ciated fragments of wall rock, and is 3 to 4 inches thick. The fissure here strikes N. 20° W., and dips 70° E. Cut number 3, 50 feet S. 18° E. from cut Number 2, is 60 feet long and 2 to 6 feet deep. The fissure here strikes N. 20° W., and dips nearly vertically. The cut exposes several diverging psilomelane veinlets, some of which contain brecciated material. The vein- lets attain a maximum thickness of 6 inches, but most of them are thinner than this. Cut number 4, located 190 feet S. 30° E. from cut number 3, is probably on a different fissure. Psilomelane veinlets are exposed at inter- vals on the surface between cuts 3 and 4, but they strike at an angle to the line between the cuts. Cut number 4 is 70 feet long and 3 to_ 8 feet deep. It exposes the best ore on the Big Bear claim, attaining a thickness of 0.5 to 1 foot. The ore averages 0.5 foot in thickness over a length of 50 feet. In part it is a high-grade banded and botryoidal oxide of the psilo- melane type, in part it consists of fragments of wall rock. The average grade of "the zone is perhaps 25 percent manganese, but a little 40 percent ore could probably be obtained by careful sorting. The main vein at this cut strikes N. 20° W., and dips 85° W. On the whole the Big Bear claim is less favorable than the Chocolate Drop claim. 76 MANOANESE IX CALIFORNIA [Bull. 152 The Black Jack claim is about half a mile west of tlie Chocolate Drop claiui. This deposit occurs iu aiulesite, which underlies the faujrlomerate of the Chocolate Drop and Bif^: Bear claims. The andesite, weathering: to a reddish color, is amyjrdaloidal, the amyg:dules beinj? lined with a pale- jrreen mineral. At least three separate veins are exposed, and numerous other veinlets cut the andesite on the surface. The westein vein crops out in three open cuts over a leufrth of 230 feet. It sti'ikes N. 15° W., and dips 65° p]. At the south end is a vein of solid oi-e 3 to 4 incites thick, wid- ening out into 8 inches of brecciated material. Thin veinlets extend into the hane is dissected by numerous barrancas. The northerly sloping benches ])etween the barrancas are underlain by a few feet of Recent or Quaternary, iniconsolidated desert gravel, whereas the barrancas are cut into the Tertiary deposits lying uneonformably benoatli the gravels. The Tertiary deposits dip to the southwest at 5° or less. The most important of the manganese bearing beds in the April Fool claim lias a thickness of 18 inches. The ore is very low in specific gravity and may be described as a porous, tuflFaceous bog manganese ore. Thin layers of pink clayey material give the ore a decided banded appearance. An assa.v of the material in ])lace yave manganese 32.2 percent ; insoluble, 30.2 percent. An assay of luuid sorted material taken from a stock pile ran : manganese, 42.9 percent; insoluble, 14.9 percent. 1950] DESCRIPTION OF DEPOSITS 81 Terfiary secfwn exposed north of Oicl Lake Thickness a. Well-consolidated conglomerate, having same general characteristics as the conglomerate at the Owl Hole mine. Unknown On the "Mn" No. 4 claim (Inyo 8) , a 0.5- to 3-foot vein of manganese oxide cuts this conglomerate. b. Gap of 125 feet, section concealed bj- gravels. c. Gray and yellow, thin-bedded, spheroidal weathering marl. 10 ft. d. Sandy gray and brown limestone, platy near the base, more massive above. 6 ft. e. Fine-grained, dusty, buff-brown sandstone with numerous thin layers of ocherous iron-stained chert. Many veinlets and druses of white opal. 75 ft. f. Sandy, porous "bog" manganese ore. 1 to 2 ft. g. Fine-grained gray and buff sandstone (tuff) . 25 ft. h. "High-grade" manganese ore — manganese oxides, principally as matrix in sandstone and as heavy coatings of grains. 1.5 to 2 ft. i. Fine grained buff and gray tuff with several thin intercalations of ore, similar in character to "h". 20 ft. j. Late boulder beds unconformably overlying members a to i, and under- lying the terrace, sloping gently northward toward the floor of the valley. No. 2. Black Bream (Wingate Wash) Deposit. (By Charles B. Hunt, 1941.) The Black Dream deposit is in Wingate Wash, probably in T. 20 N., K. 1 E. It is said to be owned by Eoy C. Troeger and leased to Cuddeback, Dorris, and Flaharty of Bakersfield. The ore body is a fissure deposit in a Tertiary conglomerate and sandstone and is broken by many small cross faults. Sooty manganese is found in short lenses throughout a zone 50 to 75 feet wide. Iron oxide and calcite are plentiful. The largest individual lens is 3 feet wide. Many lenses are less than 8 inches in thickness. The average grade is estimated to be 25 percent man- ganese. The deposit was undeveloped when visited. No. 3. Campbell Deposit. (From files of U. S. Geological Survey, 1918.) A deposit owaied by W. D. Campbell of Bakersfield is reported from Death Yalle}'. The location is unknown. It may be one of the claims in the Owls Head district. Many small fissures less than 1 foot in thick- ness are found throughout a zone 50 feet wide. The deposit has not been developed. No. 4. Connard Brothers Claims. (California Min. Bur. Bull. 76, p. 36, 1918.) "The Connard Bros, of New Jersey own 3 manganese claims on the northeast slope of the Panamint ^Mountains, opposite the south end of Death Valley, and 32 miles west of Zabriskie, a station on the Tonopah and Tidewater Railroad. They are near the old Borax road to Death Valley. The deposit consists of streaks of psilomelane 6'' to 8" wide on both Avails of a bed of calcite striking north and south in rhyolite. A spur vein 2 ft. in width which strikes N. 60 degrees E. and has a dip of 60 degrees, cuts into the main north and south vein at an elevation of 1,000 ft. Only a small amount of development work has been done, but sufficient to show this deposit to be limited to narrow veins from which but little ore could be produced. " No. 5. Death Valley (Manganese Nos. 1 to 6) Claims. (Modified slightly from original description in California Min. Bur. Bull. 76, p. 36, 1918.) The Death Valley or Manganese Nos. 1 to 6 claims are crossed by the old Death Valley Borax road and are located in the immediate vicinity 82 MANGANESE IN CALIFORNIA [Bull. 152 of the Conuard Brothers (Inj'O 4) claim. The deposit is of the same general character. The owners are E. P. Underwood, L. G. Henderson, and associates of Barstow. On the southwest side of tlie road are a number of stringers of manganese oxide cutting rliyolite and andesitic breccia. The stringers range from a few indies to 8 inches in width and form a series of parallel veins, wliich strike N. 50° E. The altitude is 1,400 feet. Of the nine full claims embraced in this property, six called the Manga- nese Nos. 1, 2, 3, 4, 5, and 6 are on the northwest side of tlie road. Through these claims extends a series of calcite veins that cut the volcanic rocks. The veins strike N. 50° W., and dij) to the northeast. The ore occurs as streaks 6 to 8 inches wide along both walls of these veins. It is high grade psilomelane but the quantity is small. No. 6. Gcronimo Prospect. (By Spangler Kicker, 1942.) A small deposit called the Geronimo prospect is 10 miles east of Olancha, probably in T. 19 S., K. 38 E. Ben Grier of San Pedro is said to be the owner. The deposit consists of low-grade oxide in lava. It has not been developed. No. 7. Lillie (Mature Consotidated) Mine. (By Ivan F. Wilson, October 17, 1942.) The Lillie mine is on the west slope of the Slate Range in sees. 14, 15, 20, and 21, T. 23 S., R. 43 E. It is 11.1 miles by road north- northeast of Trona; 7.8 miles north along the road toward Ballarat, then 3.3 miles east along an unimproved dirt road. The nearest shipping point is Trona on the Trona Railroad. The mine is on the side of a canyon on a steep south slope at an elevation of 3,000 feet. This canyon heads near B. M. 3927 on the Searles Lake quadrangle. A claim notice states that Lillie Claim No. 1 was recorded July 8, 1937 by Harold Chappelle of Bakersfield. This is probably the claim known during the last war as Mature Consolidated owned by F. "W. Chappelle and L. B. Crow. The property was idle when visited, and appeared to have been for some time. Most of the development on the property was for gold, silver, and perhaps copper. A long tunnel has been driven into the slope starting from near the bottom of the canyon. The only manganese development consists of a few small shallow cuts. The largest of these is an L-shaped cut, 3 feet wide and as much as 12 feet deep at the face, extending north- ward into the hill across the strike, and eastward following the strike, about 20 feet in both directions. The manganese ore is in a series of metamorphosed sedimentary rocks on the hanging wall of an intrusive granite. The bottom of the canyon is granite and its upper contact occurs about a third of the Avay up the slope to the north. Iri-cgular shaped apophyses of granite and several quartz veins extend into the metamorphic rocks. The metamoi'phic series includes two belts of gray crystalline limestone or marble. These strike east and dip 30° N. The manganese occurs in a gossan zone in irregular areas, mostly at the footwall of the limestone. The gossan includes manganese and iron oxides, accompanied by bi'own jasper and (puirtz vein material, and in places by sulphur and gypsum. In the upper limestone is one gossan area about 20 by 20 feet, and some othei- masses 1 foot to 3 feet thick and 20 to 30 feet long along the footwall. ^Mucli of the manganese in these areas is in tlie form of crusts or stains. The lower limestone contains at the footwall a gossan zone 2 to 3 feet thick expo.sed for 30 feet in the L-shajied cut mentioned. Another zone 20 feet long crops out 70 feet to the west. 1950] DESCRIPTION OF DEPOSITS 83 In addition, thin veinlets of oxidized material 2 to 3 inches thick lie in the limestone. Microscopic studies in 1918 showed that the manganese oxides are derived from a gedrite rock associated with anthophvllite, and from a garnet rock occurring in a quartz-garnet-amphibole rock enclosing the limestone bodies. It was concluded that the manganese might be a meta- morphosed sedimentary bed, and that the quartz-garnet-amphibole rock represents altered siliceous sediments. About 20 tons of ore has been piled on the dump at the bottom of the canj^on. It includes psilomelane, in part botryoidal, pyrolusite, iron oxides, and unoxidized pyroxene (?). The grade is estimated to be between 20 and 30 percent manganese. Assays from previous investiga- tions showed 28 percent manganese, 14 percent iron, and 23 percent silica. No. 8. Manganese No. 1 and No. 4 Claims. (By F. S. Hudson and R. R. Morse, October 11, 1918.) The Manganese No. 1 and No. 4 claims are a quarter of a mile southeast and three-eighths of a mile east, respec- tively, of the April Fool deposit (Inyo 1). They are in see. 33, T. 21 N., R. 2 E. and are owned by Thomas Keegan, J. D. Gray, and Ed Miley of Tecopa. The claims are undeveloped. The deposits consist of impure bedded manganese oxide in a series of sandstone and conglomerate. In the No. 1 claim the maximum thickness of the ore bed is 30 inches, of which the upper 8 inches is the richest. A sample across the entire thickness of 30 inches contained 20 percent manganese and more than 40 percent silica. In the No. 4 claim, the sediments are cut by a vein of hard, metallic, black oxide carrj-ing scattered boulders of waste rock. This vein strikes N. 60° W., and dips steeph^ toward the north. It ranges in thickness from 0.5 foot to 3 feet and is exposed for a distance of 25 feet. The manganese oxide appears to be of good grade, but the deposit had not been developed when visited. No. 9. Orr Claim. (From files of U. S. Geological Survey, 1942.) A deposit owned by Frank W. Orr of Bakersfield is 40 miles from Sho- shone, probably in T. 20 N., R. 1 E. It may be in the same area as the War Baby deposit of Wingate Wash (Inyo 11). If so it probably is a bedded deposit low in manganese. No. 10. Runge Claim. (From files of U. S. Geological Survey, 1918.) A deposit, said to be owned by Chris Runge of Keeler, is in T. 18 S., R. 38 E., 8 miles south of Keeler and 1 mile west of the road to Darwin. About 6 tons of ore is said to have been mined but the grade was too low to ship. No. 11. War Baly (Wingate Wash) Deposit. (By C. B. Hunt, 1941.) The War Baby deposit is in the Wingate Wash, in T. 20 N., R. 1 E., in the same general area as the Black Dream deposit (Inyo 2). It is said to be leased to Cuddeback, Dorris and Flaharty of Bakersfield. The ore body consists of bedded manganese oxide in conglomerate and sand- stone, in contrast with the Black Dream deposit which is a fissure deposit. Three beds of manganese are found in a zone 10 to 12 feet thick. The grade is low, probably not over 5 percent manganese. 84 MANGANESE IN CALIFORNIA [Bull. 152 KERN COUNTY No. 1. Apache Claim. (By Span^ler Ricker, 1942.) The Apache claim is 5 miles west of Garloek, ])robably in T. 29 S., R. 38 E. It is said to be owned by Richard Hamilton of Randsbure Avest of Lebee, in the mountainous region at the head of Pleito Creek. It is in the Mt. Finos quadrangle in the Los Padres National Forest, probably in sec. 12, T. 9 N., R. 21 W. The property is reached by driving west from Lebec along the road through Fi-azior Park into Cuddy Valley for 13 miles, then turning north along a Forest Service dirt road, signed "Neason Ridge Trail," for l.G miles to the top of the ridge and end of the road. From here a trail is taken toward the west for 350 feet, thence a branch to the north for 3 miles along the ridge to its end in a saddle. One deposit is on the southwest slope 850 feet below the top of the ridge and another is 400 feet farther down the slope. The total distance from Lebec is 17.5 miles (14.5 by road, 3 by trail). The nearest rail point is 53.5 miles south- east at Saugus on tlie Southern Pacific Railroad. The owner of the claim is R. C. Cuddy. Siliceous manganiferous rock enclosed in a highlj* quartzose coarse- grained quartz-mica schist is found over a fairly large area. Granitic rocks undei'lie most of this area. A few exposures of schist and marble are found on the property. They presumably are roof pendants in the granite. The schist has variable attitudes, but the general strike is northeast and the dip is steep to the southeast. The exact nature of the manganiferous rock is uncertain. It con- sists largely of manganese stained ([uartz. It may be a silicified part of the schist, or it originally may have been a (puirtzite which was cut by quartz veins. Manganese oxide thoroughly stains a large thickness of silicified rock, and more or less penetrates the rock. It is mostly hard psilomelane, but some soft black oxide also occurs. In places limonite stains are found. No primary manganese minerals were seen. The manganiferous rock covers one area 250 feet long and 40 feet wide in the southern part of the property. At the south end is an open cut 15 feet long, 3 feet wide, and 6 feet deep. Another small cut lies 30 feet northwest. Manganese stained rock is exposed continuously between these two cuts. The boundaries on each side are indefinite. A composite sample across the entire 40 feet contained ;5.34 percent manganese. The first mentioned cut is in a canyon trending southwestward and the manganiferous rock is not exposed south of this canyon. To the south are exposures of schist and marble. The manganiferous zone is po.ssibly truncated by a fault roughly parallel to the canyon. Fault gouge is exposed in the face of the cut in the canyon. A second cut lies at the east edge of the manganiferous zone, 150 feet northeast of the first cut. This cut is 12 feet long, 3 feet Avide, and 6 feet deep. It trends N. 50' AV. The numganilerous rock ex])osed is of a higher gratle than in the first cut. The ore body is 12 feet wide and 50 feet long. A .sample taken across the 12-foot zone contained 12.98 percent manga- 1950] DESCRIPTION OF DEPOSITS 87 nese. Lower-grade material extends west of the second cut for a total thickness of 50 feet. About 125 feet north of the second cut is a third cut which exposes a manganiferous rock that is probabh^ not continuous with the large area previously mentioned. This third cut is 15 feet long, 4 feet wide, and 6 feet deep. The attitude and boundaries of the manganiferous zone are uncertain, but the thickness is at least 5 feet. The grade is similar to that of the second cut. Two small outcrops of manganiferous rock occur up the hill to the north, 30 feet and 70 feet, respectively, from cut No. 2. Beyond this to the north is float of marble, schist, and granite. No. 10. Walsh and McChiude Claim. (From files of U. S. Geo- logical Survey, 1942.) The Walsh and McClaude claim is said to be located in T. 28 S., R. 39 E., 8 miles west of Garlock. The owner is W. J. Walsh. LAKE COUNTY No. 1. Arroyo Loho Claim. (By E. F. Davis, July 13, 1918.) The Arroyo Lobo claim is owned by Charles R. Dow of Lower Lake. It is in the NE^ sec. 3, T. 14 N., R. 7 W., and is 4 miles northwest of Arabella schoolhouse. It is 40 miles to Calistoga via Lower Lake and Middletown. The manganese deposit is northwest of the Dow Ranch in a large area of radiolarian chert. At the place where the ore is found are two zones of massive chert stained with manganese oxide. These zones strike N. 30° W. and are nearl}- vertical. They are enclosed in, and conformable with, thin- bedded red and gray chert. They may be traced 1,000 feet down the hill to the south. At several places along the course of these chert zones are exposures of siliceous black oxide ore. The westerly zone shows the largest amount of ore. In one place a short tunnel was driven years ago in an attempt to find silver beneath the outcrop of manganese. The material exposed here is a black oxide containing cores and skeletons of porous silica and also streaks and bands of compact jasperj^ silica. It is cut by veins of quartz. The thickness of the ore bed ranges from 2 to 4 feet and the exposures have a total length of 75 feet. The average grade is estimated to be 30 percent manganese and 30 percent silica. No. 2. Bell Deposit. (From Files of U. S. Geological Survey, 1918.) The Bell deposit is in sec. 31, T. 12 N., R. 5 W., in Morgan VaUey near Lower Lake. It consists of opaline iron manganese ore. The grade is reported as low. No. 3. Black Point Claim. (By E. F. Davis, July 21, 1918.) The Black Point claim was located by M. Walter Clark of Cobb Valley, upon an abandoned prospect tunnel said to have been driven years ago in search of silver ore. No development has been done recenth\ The prospect lies in sec. 21, T. 11 N., R. 8 W., on the west side of Cobb Mountain. It is 3 miles from the Calistoga-Kelseyville road and 31 miles from Calistoga. It is within 0.3 mile of an old road to a sawmill on the west side of Cobb Mountain. The country rock is mainh^ thin-bedded, red radiolarian chert. In the immediate vicinity of the prospect, the chert is discolored \>y stains and films of black manganese oxide. The ore occurs as pockets and small lenses in a thick bed of massive chert. The more siliceous parts of the ore bed form bold outcrops. The ore bed is exposed in the old prospect tunnel, which is now caved. At the upper surface the contact of the ore is essen- tially parallel to the bedding of the enclosing chert, although the contact 88 MANGANESE IN CALIFORNIA [Bull. 152 is not sharply defined. The ore body ean be traced for 300 feet. It shows a rude bandiufr in its ujjper part. The best ore occurs in pockets and lenses. A sample of a hi^h-^i-ade lens contained 42.2 percent manganese, 18.4 percent silica, and 10.4 jiercent available oxygen. No. 4. The Black I'ou-drr Claim. (By p]. F. Davis, July 15, 1918.) The Black Powder claim was located by T. ]\I. Smith of Lower Lake. It is in the NW]NE^ sec. 31, T. 12 N., R. 5 W., 1.5 miles southwest from Prank Ebenhanser's Ranch at the base of a high point composed of greenstone of the Franciscan groui>, locally known as Butte Rock or 8haly Cliflf. ]\Iotor trucks could come within a mile of this deposit if a road 0.5 mile long were built. It is then 45 miles to Winters by wagon road. The ore zone consists of a series of manganiferous beds having a total thickness of 25 feet and exposed over a length of 30 feet along the strike. A section in a creek at the nortliwest end of the ore zone exposes the beds for a length of 20 feet along their dip. The beds strike nearly northwest and dip 40° NE. The lower and middle parts of the ore zone consist of soft red, rather impure iron oxide mixed with layers of opaline iron manganese ore. The impure iron oxide, or "paint rock," is bright red to red brown in color, is soft and crushes easily to a fine powder. The opaline iron manganese ore is brittle, has a hardness of 3 to 4, and breaks witli a smooth curving fracture. Both the opaline iron manganese and the soft impure iron oxide contain considerable manganese, shown by the fact that on exposure to the air they become coated with films of black manganese oxide. A peculiar feature of this deposit is beds of nodular green chert which have a maximum thickness of 2 feet. The nodules in this chert are ellipsoidal nuisses of manganese which have the plane of longer dimension parallel to the bedding. Some nodules are 6 inches in length and 1.5 inches thick. These nodules maj- be separated easily from the matrix. When removed they are cracked as though they had shrunk. The oxide in the nodules shows a granular texture, the grains being 0.2 to 0.5 millimeter in diameter. On striking a nodule with a ham- mer one gets the peculiar imjiression that the nodule is plastic. This is probably due to the interlocking of the grains of oxide that compose the nodule. Some of the nodules show a peculiar concentric banding due to thin films of extremely fine textured manganese oxide running through the otherwise granular material. In the central parts of the larger nodules are cores composed of interlocking grains of a yellowish-green mineral with a bright vitreous luster. This mineral is probably a silicate of manganese, since all transi- tions may be fouiul between tlie fresh mineral and the soft but granular manganese oxide. Little regularity is seen in the distribution of man- ganese nodules and the bodies of chert. They may occur at any horizon in the shaly matrix. Also, the manganese nodules are not limited to one zone and the chert lenses to another. The bodies of different material may lie anywhere in the enclosing matrix. The only regularity observable in their arrangement is that the planes of longer dimensions are parallel to the bedding of the lower parts of the ore zone. The ore zone is enclosed in greenstone of the Franciscan group, but the relations of the ore to the greenstone are not clear. The ore ends abruptly at the creek, and no manganiferous rocks are found on the northwest side of the creek. The places in the creek where the base and top of the ore zone would be expected are covered with boulders. 1950] DESCRIPTION OF DEPOSITS 89 The nodnles of manganese oxide now exposed in the upper part of the ore zone are small in number. The material is a new variety of man- ganese ore in this region and it is, therefore, impossible to speak with certainty about it until analj'ses are at hand and the minerals are deter- mined in the laboratory. It is not possible to predict what changes may occur in depth, though it seems certain the primary manganese mineral is a silicate. In sec. 30, about 1,000 feet northeast of the Black Powder outcrop, a siliceous iron ore contains a little manganese. It is too low in manganese and too high in silica to have any value, though the amount present apparently is large. No. 5. Cohh Mountain (Oyster Rock) Prospect. (By E. F. Davis, July 21, 1918.) W. A. McCombs and George Hill, both of Middletown, have a prospect on the west side of Cobb Mountain near the Lake County line, probably in sec. 21, T. 11 N., R. 8 W. The location notice and prospect pit are 250 feet soutliAvest of Geyser Rock, a large rock that stands near the county line. The prospect lies 3.5 miles from the Middletown-Kelsey- ville road and is 30 miles from Calistoga. A mass of greenstone is exposed in a cut. This greenstone contains inclusions of jasper that have been metamorphosed by the heat of the intrusion. The fractures and cracks in the greenstone and jasper are stained black with manganese oxide. Fresh breaks are free from man- ganese oxide and the total amount of manganese here is small. No. 6. Coleman Prospect. (By B. F. Davis and F. S. Hudson, August 13, 1917.) The Coleman prospect is in sec. 29, T. 12 N., R. 9 W. It lies about 3 miles west of Cobb Post Office and 2 miles west of Cole- man's Ranch. A road from the ranch crosses the creek at the southeast end of the property. The owaiers are J. H. Coleman of Cobb, and J. D. Sullivan of Kelseyville. A body of massive metamorphosed red and vermilion chert, 20 to 50 feet thick, runs along High Valley Creek, trending northwest, and may be traced for 1,300 to 1,400 feet along the strike. This chert is stained on fracture planes by manganese oxide. Shearing along these fractures has developed "mirrors" of manganese oxide. In places the chert passes into a fair grade of ore but no workable body has yet been uncovered. A smaller body of chert containing manganese is exposed at a point 1.3 miles downstream. It is of the same nature as the larger body. No. 7. Copsey and Moore Prospect. (By E. F. Davis, July 5, 1918.) Arthur Copsey and AV. P. Moore of Middletown have a manganese prospect in sec. 33, T. 12 N., R. 2 W. The ore crops out in an area of ser- pentine and lies within a few feet of an exposure of greenstone of the Franciscan group. The relation of the ore to the igneous rocks is not apparent. The manganese ore is black and hard. Apparently it is a man- ganif erous chert and too siliceous to have value as a source of manganese. No. 8. Dow Prospect. (By Prank S. Simons and i\Iax D. Critten- den, Jr., July 25, 1942.) The Dow prospect is in sec. 4, T. 14 N., R. 7 W., on land owned by Carol Dow of Lower Lake. The prospect is 2 miles by trail from the Dow Ranch, which is 6 miles by a good gravel road from the Williams-Clear Lake road and 36 miles from Williams, the nearest railroad point. The prospect is 600 feet above the bottom of Quartz Canyon, a tributary of Wolf Creek. A road could be built to it rather easily. Little development has been done. 90 MANGANESE IN CALIFORNIA [BuU. 152 Tlie Dow prospect is on a ridge composed of thin-bedded red chert and siliceous siialc, with some thick bands of sandstone lying between cliert areas. Tlie oi-e bed can be traced more or less continuously for 140 feet along the strike. The lianging wall, Avhere exposed, is white chert overhiin by sandstone; the footwall is wliite chert with some interbedded shale, and is underhiin by platy red chert. The maximum thickness of ore exposed is 3 feet near tlie middle of the outcrop, and the maximum depth of exploration is 2 feet. The ore appears to be irregularly distributed along the strike of the ore bed. The strike varies from N. o5°-80° W., and the dip from 45° to 50° SW. The ore thus far exposed is soft black pyrolusite, containing cores of white to reddish brown leached chert. The best ore contains about 45 percent manganese; the average grade is nearly 35 percent. The silica content is 20 to 30 percent. The surface ore is cut by many thin quartz veins, which cause the otherwise soft ore to make resistant ridges. No. 9. Downey Estate Prospect. (By Max D. Crittenden, Jr., August 5, 1942.) The Downey Estate prospect is in the NW^ sec. 8, T. 10 N., K. 7 W., on the road from Middletown to the Helen mine, 0.1 mile west of the road to the Von CJlahn Ranch, and about 3 miles from Middle- town on land of the Downey Estate. The country rock is thin-bedded red chert, striking N. 60° W. and dipping steepl}^ northeast. A 3-foot bed of manganese ore is exposed in the edge of the creek, but the lack of development precludes estimation as to possible length or continuity. The ore consists of a smoothlj^ rounded surface of dull black oxide, but whether this is merely a coating due to leaching of manganese, or Avhether it represents an actual bed of work- able ore, is unknown. The average grade is thought to be 40 percent manganese. About 2 tons of such ore is exposed. No. 10. Ehenhauser Prospect. (By E. F. Davis, June 13, 1918.) Frank Ehenhauser of Rieff has a manganese prospect in the SW^ sec. 20, T. 12 N., R. 5 W. It is on the road from Monticello to Lower Lake, 25 miles from Monticello and 18 miles from Rumsey. The prospect is on the main road 0.5 mile east of the house. The material exposed is opaline iron manganese ore containing less than 10 percent manganese. Associated with this ore are lenses of a yellow, rather porous chert, together with some lenses of red compact jasper. A fine-grained greenstone is exposed at several points within a few feet of the ore bed, but it was not possible to determine the relationships. At one point an old tunnel runs into the ore for a few feet. About 250 tons of this opaline iron manganese ore is present. No. 11. Elliott Prospect. (By Frank S. Simons and Max D. Crittenden, Jr., July 24, 1942.) The Elliott prospect is in sec. 25 or 26, T. 12 N., R. 9 W., near the county boundary point common to Lake, Mendocino, and Sonoma Counties. The prospect is on government land controlled by Frank Elliott of Whispering Pines, and is leased to the Strategic Minerals Company, Ltd., of San Francisco. Tlie prospect is 3.8 miles from the Cobb-Kelseyville road, 6.8 miles from Cobb, and 43 miles north of Santa Rosa, the nearest railroad point. Water is available a few hundred feet from the prospect. An open cut 300 feet long exposes massive, sheared and slickensided, manganiferous brown chert. The face exposed is 30 feet high. The atti- tude of the chert is concealed by faulting but it is about northwest in 1950] DESCRIPTION OF DEPOSITS 91 strike. Greenstone forms the southwest wall at the southeast end of the cut. At the northwest end, the chert is faulted apainst a fresh porphyritic greenstone. The strike is N. 45° W., and the dip 35° NE. The fault is vertical and strikes N. 80° W. The ore found thus far consists mainly of manganiferous chert, con- taining 5 to 10 percent manganese, and 60 percent silica. Small amounts of hard blue psilomelane and soft black pyrolusite are present, but these oxides usually are in thin seams and along shear zones. The ore zone is at least 20 feet thick, and can be traced intermittentl.y for 0.5 mile south- east along the strike. At no place, however, is anything but manganiferous chert exposed. No. 12. Gravelly Valley Deposit. (By Max D. Crittenden, Jr., October 6, 1942.) The Gravelly Valley deposit is near the center of sec. 3, T. 18 N., R. 10 W. The nearest shipping point is Ukiah, a distance of 35 miles. The Gravelly Valley mine is owned by Ed George and the McCullough brothers. At the time the mine was examined, a bulldozer was on the property ready to begin construction of an access road. The work at the property consists of two adits and a number of open pits and prospect holes. The Gravelly Valley mine is in an intensely folded and sheared area of chert and sandstone of the Franciscan group. The general trend of the beds seems to be N. 60° W., parallel to the ravine in which they lie. Small scale faulting is common, and has produced many local brecciated areas. Manganiferous beds, originally present in the chert, have been sheared and broken by this deformation, and are thus especially suscepti- ble to the leaching and oxidizing action of surface water. The result has been the formation of friable, medium-grade oxide ores in locally brecciated areas, from primary material that appears to have been manganiferous chert, hydrous manganese silicates, or disseminated man- ganese carbonate. The grade of the primary ore is thought to have been 20 to 30 percent manganese. The ore exposed is friable black oxide, with powdery and ocherous cores representing the original cherty or siliceous parts of the primary ore. This ore has been exposed at several places, only three of which appear to hold promise. These are along the northern side of a ravine that trends N. 30° W., and slopes toward the upper end of Lake Pillsbury. The horizontal linear distance between the outermost exposures is prob- ably 150 feet. There is but one intermediate exposure of ore, and in detail, the bodies that have been followed in the development work appear to be lenticular faulted masses. No. 13. The Hermann Claims. (By E. F. Davis, June 8, 1918.) Henry Hermann of Middleton has located several claims on bodies of manganiferous iron ore near the Hermann Ranch on Bucksnort Creek, 11 miles east of Middletown. The Hermann claim is near the center of sec. 20, T. 11 N., R. 5 W., 1.5 mile northeast of the Hermann Ranch. A shallow trench has been sunk on an outcrop of massive manganese- stained jasper. The trench exposes a little siliceous iron ore carrying small amounts of manganese. A sample taken here gave 6.1 percent manganese, 52.0 percent iron and 18.3 percent silica. No. 14. Herndon (Manganese No. 1) Claim. (By E. F. Davis, July 2, 1918.) The Herndon claim was located by N. W. Herndon of Lower Lake. It is in sec. 22, T. 14 N., R. 6 AV. It is reached from Lower Lake by going 10 miles east on the Sulphur Creek road from Lower 92 MANGANESE IX CALIFORNIA | Bull. 152 Lake to "Williams, to the north lork of Cache Creek, then following the north fork of Cache Ci-eok to lion Moore Canyon, and up Ben Moore Canyon to the Old llern(h)n sheep camp 18 miles from Lower Lake. The claim lies east of Ihe old camp, 0.8 mile from the summit of the ridjre on the east side of Ben Moore (Janyon. If ore were hauled from this claim it could he hrou.<>ht down in a wagon, with a little brush cutting, to Ben Moore Creek. With a small amount of work a road could be built down this creek joining the road along Cache Creek. The total distance from the railroad at Calistoga is 4G miles. The Avork on this ]n"operty consists of a single trench 20 feet long. The ore occurs in a body of radiolarian chert of the Franciscan group which dips 45° N., and strikes N. 60° W. The total thickness of the ore and the radiolarian chert is 25 feet. The beds of ore and the chert are parallel throughout the section. The chei't is bounded on the north by greenstone. The geologic relations between the chert and the green- stone are not clear. Near the base of the exposed section of radiolarian chert is a massive bed of red chert containing curving veinlets of white ([uartz. Li some places this type of quartz veining is in radiolarian chert found near the contact with intrusive basalt of the Franciscan. With this exception, there is no evidence of intrusion or metamorphism of the chert by the greenstone. The radiolarian chert and manganese ore beds are cut by small faults which render the sequence uncertain. The radiolarian chert is deep brick red. Li part it is massive ; in part thin-bedded. The aggregate thickness is 10 feet. Where thin-bedded, the chert is generally separated by thin joartings of soft red impure iron oxide (paint rock). The aggregate thickness of iron oxide beds is 5 feet. Green chert beds with a granular texture are also present. These beds range from 2 to 4 inches in thickness and are separated by partings of impure red iron oxide. They have a total tiiickne.ss of 3 feet. One 6-inch bed ajjpears within a zone of massive green chert and red iron oxide partings. It is laminated, the laminae being about one-eighth inch in thickness and consisting of bands of a dark steel-gray to black mineral and of siliceous yellow limonite. The dark-colored mineral is crystallized in minute grains. Its streak is dark red, and it was determined in the field as hematite. In a few places it appeared to be mixed with psilomelane. About 7 feet of the exposed section is composed of opaline iron manganese ore. This ore is generally massive and does not show the tendency to thin bedding exhibited bj' the associated cherts. It has a hardness of about 4, and is brittle, crushing easily to a dark brown to red powder; and on fresh fractures shows a brilliant waxy luster. The color varies with the proportion of iron and manganese in the opal. Some varieties are bright cherry red. These show no change on exposure to the weather. Others ar(> pale chocolate brown to reddish brown. On exposure to the weather these varieties become quickly coated with a film of black manganese oxide. The red-bi'own variety may show a tendency to spherulitic structure. On examining it with a hand lens, spots of light-brown color, nearly circular in outline, may be dis- tinguished in a matrix of darker material. In a few places thin partings of red-brown opaline matei-ial form the parting between thin beds of bright-red chert containing numerous radiolarian skeletons. A consider- able amount of the granular hematite in laminated form is exposed in an open pit 100 feet west of the main ore body. 1950] DESCRIPTION OF DEPOSITS 93 No. 15. Herrick Prospect. (By E. F. Davis and F. S. Hudson, August 10, 1917.) The Herrick prospect is in the SEiSE-l sec. 25, T. 11 N., R. 8 W., about 3 miles west of Middletown. The owner is S. B. Herrick of Middletown. The ore body is a massive bed, 3 feet in thickness, enclosed in well-bedded red chert, and lying parallel to the bedding. It has been exposed by a small open cut. Greenstone is seen in contact with the enclos- ing chert 120 feet north of the open cut. Apart from a few small pockets, the ore body is siliceous, consisting mostly of original massive jasper, veined by quartz and cut by thin veinlets of manganese oxide. The local pockets of manganese oxide are rendered worthless by numerous quartz veins. The bed of the creek, which flows to the northwest passing a few yards to the south of the prospect, is full of boulders and pebbles of red chert. Fifty yards upstream from the manganese prospect a 6-inch boulder of soft rich manganese ore was found. Farther upstream several boulders of low-grade ore were seen. From the amount of float in the creek it is thought that a large body of red chert is here, and the presence of many fragments of manganese ore in the creek probably indicates the existence of a considerable body of ore within this drainage area. No. 16. La Bree (Manganese No. 2) Claim. (By B. F. Davis, July 12, 1918.) The La Bree claim was located by Jack La Bree of Lower Lake. A location notice was afterward put on it by J. H. Bigelow of St. Helena, but no work was done on it by him. Only a small amount of work was done by the original discoverer. This consisted in digging a few shallow pits. The claim is in sec. 22, T. 14 N., R. 6 AV., and adjoins the claim located by N. W. Herndon and known as the Herndon or Manganese No. 1 (Lake 14) claim. It is 46 miles from Calistoga. The relations here are much the same as those on the Herndon claim. In fact La Bree's claim lies just 750 feet west of Herndon 's claim and appears to be on a continuation of the same body of radiolarian chert. The chert is bounded by greenstone. The relations of greenstone to the chert are not determinable. The chert is thin-bedded and is separated by partings of impure red iron oxide. There are also several exposures of green and yellow chert, rather massive in structure, and containing much crystalline quartz. A few thin beds of fine-grained hematite banded with siliceous yellow ocher are also present. In some of this material are bands of psilomelane. No. 17. Little Falls Deposit. (By Max D. Crittenden, Jr., August 6, 1942.) The Little Falls deposit is in sec. 25, T. 12 N., R. 9 W., and is owned by James Gunn, Jr., of Kelseyville. It is 0.5 mile from the road along Kelsey Creek. Red thick-bedded chert, locally sheared, with dark shaly material along the sheer planes, shows manganese-stained joint surfaces over a considerable area. Bedding is obscure, and the strike is highly variable. Small quantities of ore appear on or near the surface due to surface concentration. Small pieces can be found that contain 30 percent manganese, but most is well under 10 percent. No. 18. M. & G. Claim. (By E. F. Davis, July 13, 1918.) The M. & G. claim was located by Jack La Bree of Lower Lake. It is in sec. 34, T. 14 N., R. 7 W., and is 8.8 miles north of Lower Lake, and 43 miles from Calistoga. The deposit is 0.2 mile from the Lower Lake-Arabella road. An open cut has been opened into the hillside for a distance of 15 feet. 94 MANGANESE IN CALIFORNIA [Bull. 152 The ore body is uiulerlaiii by tli in-bedded, ash-colored chert of some- what i)orous textui'c separated by thin i)artings of black oxide of man- ganese. It is overlain by thin-bedded white chert containing only a trace of manganese. The ore body lies parallel to the bedding of the enclosing chert. The dip of these beds is 30° S., a little lower than the angle of the hill sh)i)e here; the strike is N. 75° W. The ore body is 2 feet thick and is low in manganese and liigh in silica. No. 19. Mead Prosjycct. (By Frank S. Simons and Max D. Crit- tenden, Jr., July 24, 1942.) The Mead prospect is on land owned by Ray Mead of Middletown in sec. 35, T. 11 N., R. 8 W., on the ridge betAveen Bear Canyon and Gunning Creeks. It is 5 miles by road and 1 mile by trail northwest of Middletown. and 20 miles north-northeast of Calistoga, the nearest railroad point. The area is heavily soil covered. On the crest of a small ridge is an outcrop of manganiferous chert striking east and dipping 50° S. One hundred feet below the ridge and scattered along the creek bottom for several hundred feet are numerous blocks of the same rock, some weighing 500 pounds. Manganiferous chert crops out at onlj'^ one place ; so the strike, length, and thickness are unknown. The best ore is a soft black manganese oxide containing about 35 percent manganese. The amount of this ore is small, and the average grade of all ore in sight is probably 15 percent manganese. Most of the ore is siliceous and is cut by numerous small quartz veins. The oxides form thin films along fractures. No. 20. Myers (Red Bay) Prospect. (By E. F. Davis, July 5, 1918.) The Ben F. M.yers or Red Bay prospect is 1 mile from the road between Clear Lake and "Williams, 35 miles from "Williams in sec. 35, T. 13 N., R. 6 W. This property was not visited but from Mr. Myers' description of the ore the deposit is chiefly composed of low-grade, opaline iron manganese ore. The best ore according to Mr. Myers contained 12 percent manganese and 60 percent iron. No. 21. Old Bougli Claim. (Modified slightly from original description in California Min. Bur. Rept. 17, p. 78, 1921.) This deposit was discovered in 1919 by J. E. Rees of Middletown, and one claim, the Old Dough, was located in 1920. It is in T. 12 N., R. 9 W., at an altitude of 2,700 feet. The nearest railroad station is Calistoga, 30 miles by good road. An ample supply of water is at hand. The deposit is said to be large and most of it is low grade. A few high-grade pockets are present. The deposit was undeveloped when visited. No. 22. Ova Hans Prospect. (By E. F. Davis, June 13, 1918.) Ora Hans of Reiff owns a manganese prospect in the S"W| sec. 20, T. 12 N., R. 5 W. It is exposed on the hillside close to the road from Knoxville to Lower Lake. The material consists of opaline iron manganese ore with less than 10 percent manganese. It contains silica in the form of porous, sometimes almost powdery cores. Greenish opal is found near the center of some of the larger blocks. The amount of manganiferous material on this propertv is small. No. 23.' Overlook Claim. (By E. F. Davis, July 23, 1918.) James D. O'Brien and R. C. INIiller of Kelseyville, have a manganese claim 0.2 mile north of the second milopost west of Highland Springs on the High- land Springs-Pieta road. The prospect is in sec. 33, T. 13 N., R. 10 W. Pieta, the ship])ing point on the Northwestern Pacific Railroad, is 13 miles distant. The deposit is a siliceous iron ore with interbedded chert. Some 1950] DESCRIPTION OF DEPOSITS 95 parts of the main body are composed of opaline iron ore. A few lenses of massive chert cut by veinlets of manganese oxide are intercalated in the iron ore. Some of the chert lenses are pink and are porous ; others are red and contain radiolaria. The radiolarian chert beds occur as groups of thin beds in the iron ore, separated from one another by thin red partings of the iron ore. The iron mineral is easily scratched with a knife and crushes readily to a soft red powder. The deposit may be described as an iron oxide deposit showing manganese stains on weathered surfaces. It is of no commercial value, as it has too much silica and too little manganese. The iron deposit is entirely surrounded by outcrops of greenstone of the Franciscan group, some of which show a marked pillow structure. The relations between the ore and the igneous rock cannot be determined as none of the contacts are exposed. No. 24. Phillips Mine. (By E. F. Davis and A. 0. Woodford, August 3, 1918.) The Phillips manganese mine is on land owned by W. S. Phillips of Bechelor, Lake County. It was formerly leased to Lew Thorne and Son of San Francisco. It is in sec. 16, T. 15 N., R. 10 W., and is best reached from Ukiah, by the wa.y of the Blue Lakes road from Ukiah to Laurel Dell. The mine lies 1.5 miles by trail from Laurel Dell, and is on the summit of a high peak which is S. 42° E. of the Laurel Dell Hotel. Ukiah is the nearest railroad point and is 21 miles from Laurel Dell over good road. The northern and lower part of the mountain on which the mine is located is composed of sandstone of the Franciscan group, but near the summit considerable radiolarian chert is intercalated in the sandstone. This radiolarian chert strikes north and dips steeply west. Almost every body of chert yields manganese ore at some place within this area. Except as noted below the ore is of one type. It is black oxide of manganese, usually rather soft and breaking easily with a hammer. On fresh fractures it shows a dull metallic luster. The specific gravity is high and the ore as examined in the field was judged to run about 45 to 50 percent of metallic manganese and 10 percent of silica. All the ore removed has come from shallow open cuts. The ore occurs in lenses in the red chert. These lenses lie parallel to the bedding. They are in some places associated with lenses of massive red or yellow chert but at other places the ore bodies are simply enclosed in red shale and chert without any associated thick chert beds. Several ore bodies have been worked near the south end of the ridge on the summit of the mountain. They consist of small bodies of chert that show black stains of manganese oxide. No other ore was seen. The No. 2 working lies at the south end of the summit of the ridge. Here an open cut across the top of the ridge has not penetrated the loose surface material. The red soil contains numerous small angular frag- ments of red chert together with blocks of yellow, manganese-stained chert. In addition many blocks of high-grade manganese ore, ranging in size up to a half ton are exposed. The No. 1 working lies on the west side of the ridge 300 feet south- west of the No. 2 working, 60 feet vertically below the summit. The ore is in the same body of chert as the ore at working No. 2. The working here was an open cut. The sides have caved so that the mode of occurrence of the ore body and its relations are not determinable. An examination of the material extracted and piled on the dump indicates that the ore occurs in 96 MANGANESE IX CALIFORNIA [Bull. 152 intimate association with a bed of red jasper cut by veinlets of manganese oxide. The ore is estimated to contain 20 percent nianjifanese. The No. '.i working lies on the summit of the ridge 200 feet north of the Xo. 2 working. Here a lenticular bed of high-grade manganese ore is enclosed within thin-bedded reil radiolarian chert and red siliceous shale. The thickness of the ore body ranges between 10 inches and 3 feet. In one place it is seen to wedge upward. The ore body and enclosing chert strike N. 20° W. and dip about 80" NE. On the hanging wall the ore is overlain by 4 to 7 feet of siliceous red shale. Overlying this red shale is coarse-grained sandstone. On the foot- wall side is red radiolarian chert with sliale partings. The No. 4 working starts at the top of the ridge 40 feet north of No. 3 working. Here an open cut 8 feet long and 4 feet deep has been dug, and ore has been removed. No important amount of ore is exposed here now, but from small pockets that are left, it seems certain that the ore lay above a bed of massive yellow and red jasper 2 to 3 feet thick and that both ore and massive jasper were essentially parallel to the enclosing thin- bedded chert and shale. The other No. 4 woi'king consists of pits and trenches sunk along the ore zone. Tlie ore zone is traceable for 100 feet down the west slope of the sunnnit ridge to a point at an elevation of 25 feet below the crest of the ridge. At its west end the massive red and yellow chert has disappeared from the ore zone and the body of high-grade ore 5 inclies thick is enclosed in thin-bedded red radiolarian chert and shale. Midway between the two extremities is a thickness of 4 feet of high-grade ore enclosed in red radiolarian chert and shale. The No. 5 working is 100 feet west of No. 3 on the west side of the summit ridge. It is 25 feet southwest of the most westerly working of the No. 4 group. At this place a trench-like open cut was run into the hillside in thin-bedded soft red shale and radiolarian chert, which strike N. 45° E. and are vertical. No ore is in sight but the form of the cut suggests that the ore body was a lens parallel to the bedding of the enclosing chert. The ore contains 42 percent manganese and 18 percent silica. The No. 6 working is 200 feet north of No. 4 at an altitude of 50 feet below the sunnnit of the ridge. Here a small open cut exposes broken blocks of chert in a red soil containing many blocks of high-grade manga- nese ore. In the extreme end of the cut massive yellow chert is exposed beneath a cover of soil. This chert contains a bed of high-grade manganese ore 3 inches thick. The soil above this massive chert is mantled by blocks of high-grade ore, indicating another source of ore farther up the hill. About 500 pounds of high-grade ore is piled here, having been removed from the open cut. The No. 7 working is near the top of the ridge on its west slope about 300 feet north of No. 6. Here a massive lens of yellow, red, and red-brown jasper, having a maximum width of 8 feet and an exposed length of 20 feet, is seen in an open cut. It stands nearly vertical and trends northwest. The jasper contains pockets of high-grade ore but the amount of such ore is small. Ten feet northwest of this lens is another small pocket of high- grade ore. The Xo. 8 working is a small open cut 200 feet west of No. 6, and is at an altitude of 75 feet below the top of the ridge. Here a quarter of a ton of high-grade ore was removed from a trench. The ore was all in loose blocks in the soil and none Avas in place. 1950] DESCRIPTION OF DEPOSITS 97 This property was visited by Max D. Crittenden, Jr., in 1942. It had been idle since World AYar I but had been worked after it was visited by E. F. Davis in 1918, the total production being 400 or 500 tons. No. 25. Eainhow Ledge Prospect. (By Max D. Crittenden, Jr., August 6, 1942.) The Rainbow Ledge prospect is on the property of 0. B. Tj-rer and a Mr. Ersldne of Lakeport, in the SE^NWi sec. 35, T. 15 N., R. 10 W. To reach this deposit from Lakeport, take the Scott Valley road, turn right at 5.9 miles across a small bridge, and at 6.7 miles turn right again over a small bridge. The property is 1.4 miles beyond this turn, on a ranch road. An open cut, 20 b}- 12 by 8 feet, comprises the development on this property. The cut is located in a narrow lens of chert. The maximum thickness of the chert is 20 feet. The rocks have been sheared. A cross fault at the mouth of the cut appears to offset the ore. The ore bed shows a length of 15 feet, and ranges from 2 inches to a foot in width, but aver- ages 10 inches. The ore is largely oxide, containing 45 to 55 percent manganese, and 10 to 22 percent silica. The ore body is reported to widen downward. No. 26. Rattlesnake Deposit. (By E. F. Davis, June 8, 1918.) The Rattlesnake deposit is in the SW^ sec. 29, T. 11 N., R. 5 W., near the Hermann claim (Lake 3). It is owned by 0. E. Hermann. The ore con- sists of blocks of siliceous manganiferous iron ore in greenstone and serpentine. The blocks are found over an area of 60 by 40 feet. The largest blocks are 8 feet in diameter. The deposit has produced no ore. No. 27. Rose Ranch Prospect. (By Max D. Crittenden, Jr., August 7, 1942.) The Rose Ranch prospect is owned by F. H. Rose of Upper Lake. It is in sec. 10, T. 15 N., R. 9 W., and is 6.2 miles by road northeast of Upper Lake. The deposit is located on a good-sized landslide in terrain typical of the Franciscan group. North of the house, in the scarp produced by the slide, lenses of thin-bedded red chert are interbedded or associated "with sandstone, greenstone, and conglomerate of the Fran- ciscan. Two open cuts have been made, one 350 feet northwest of the house, the other, 500 feet east of the house, but both expose only stained red chert with greeni.sh shale interbeds. The general strike of the chert north- west of the house is N. 65° E., the dip, 35° to 40° N. No ore is exposed except some landslide blocks southeast of the house. Here surface concentration produced thin layers of oxide ore that gave assa.vs as high as 54 percent manganese. The primary material, however, probably did not assay over 10 percent manganese. No. 28. SmytJie Manganese Prospect. (Condensed from original description in California Min. Bur. Rept. 17, p. 79, 1921.) The Smythe deposit, owned by T. A. Smythe of ]\Iiddletown, is on a branch of Dry Creek, 3 miles west of Middletown in T. 10 N., R. 7 W. A good road runs within 0.5 mile of the prospect. The deposit was discovered in 1918. It crops out high on the steep side of a hill at an altitude of 1,800 feet. A lens of good ore crops out for 30 to 40 feet. It is 2.5 to 3 feet wide, strikes nearly north and dips into the hill at an angle of 45°. The country rock is sandstone and chert. Two or three tons had been taken out at the time of visit. No. 29. Spring Bill Farm Deposit. (By E. F. Davis, June 7, 1918.) R. Peterson has discovered float of manganese on his ranch, the Spring Hill Farm, 5 miles west of Middleto^vn on the road to the Helen 4 — 11208 98 MANGANESE IN CALIFORNIA [BuU. 152 mine. The deposit is believed to be in sec. 30, T. 11 N., R. 7 W. No ore body 1ms been discovered though some prospecting lias been done. In places along the road to the Helen mine, at a distance of 3 to 4 miles from Middle- town, massive beds of chert are enclosed in thin-bedded chert showing stains of manganese and small amounts of ore. Nothing of commercial imijortance has j^et been found in this vicinity. No. 30. Summit Deposit. (By Max D. Crittenden, Jr., August 7, 1942.) The Summit deposit is located on the summit of the ridge west of Clear Lake, 0.8 mile south, by trail, of the highest point of the Lakeport- Hoplaud road. The probable location is sec. 2 or 11, T. 13 N., K. 11 W. It was located by A. H. Iloyt of Kelseyville. An open cut 30 feet long by 10 feet wide, and 5 to 6 feet deep exposes rather massive red chert, contain- ing veinlets and interbeds of secondary oxide ore of good grade, separated by chert beds 1 inch to 12 inches thick. The chert strikes roughly east and dips 30° S. Small scale faulting and shearing is common. The total length exposed is 30 feet. The average grade of the ore body is estimated to be 30 percent manganese. No. 31. Vann Ranch (Black Rock, Grizzly Canyon, Middle Creek) Prospect. (By Frank S. Simons and Max D. Crittenden Jr., July 23, 1942.) The Vann Ranch or Middle Creek prospect is in sec. 34, T. 17 N., R. 10 W., on the south slope of Horse Mountain between Grizzly Creek and the west fork of Middle Creek. It is 11.4 miles north-northwest of Upper Lake, and 37 miles from Ukiah, the nearest shipping point. The last 2 miles of the road are rather rough, especially at the fords of Middle Creek and Grizzly Creek. The road extends to within a quarter of a mile of the mine, at which point is a sulphur spring. The ore was sledded down the last quarter of a mile. The ore deposit is in a rather narrow band of thin-bedded buff, shaly chert, bordered by brown, somewhat micaceous sandstone. The ore body is exposed intermittently for 125 feet along the strike. At the last exposure at the southeast end, an open cut exposes 6 feet of manganiferous chert, striking N. 80° W. and dipping 40° NE. into the hillside. The chert here contains a few thin partings of high-grade pyrolusite ore, but the greatest part of the ore has less than 20 percent manganese. Seventy feet north- west of this cut are several ver}- promising outcrops of manganese ore, and 30 feet farther northwest an open cut and an adit 40 feet long expose 3 to 4 feet of siliceous manganese oxide ore, striking N. 35° W., and dipping 45° NE. A shallow winze at the end of the adit shows that the ore extends at least 15 feet below the surface. The ore at this depth shows no improvement over the ore near the surface, and there is no reason to think that additional depth will result in any higher-grade ore. Twenty feet northwest of the adit, an open cut in brecciated buff chert exposes a small amount of oxide staining the chert. The chert here strikes N. 60° W. and dips 10° NE. (probably somewhat slumped). The ore wherever seen is a siliceous oxide ore, cut by many quartz veins. No ore was seen that contained more than 35 percent manganese, except a few thin pyrolusite partings, and the average grade is probably not over 25 percent manganese. The deposit could not be worked profitably at present market conditions. No. 32. Von Glahn Prospects. (By Max D. Crittenden Jr., August 5, 1942.) The Von Glahn prospects are in the SW^ sec. 5, T. 10 N., R. 7. W., on the property of Henry Von Glahn of Middletown. They are 1950] DESCRIPTION OF DEPOSITS 99 located 0.2 to 0.5 mile off the road to the Von Glahn house, and 3.5 miles from Middleto-wTi. In 1935 about 20 tons of ore was shipped from this property. It is reported to have assayed from 18 to 47 percent manganese, but to have been rather high in silica. Several prospects are present, but all are low in grade and small in size. One prospect lies along the stream above the Von Glahn ranch, and is 20 feet above the creek. The workings consist of a 15-foot trench cut into the hill, and three small open pits. These expose sheared chert of the Franciscan group striking N. 20° W., and dipping 20° to 30° NE. The openings along shear planes are filled with secondary quartz and man- ganese oxides. The over-all grade of the ore is low. The second prospect is located 250 to 300 feet up the slope from the first, and consists of an open cut 20 feet long. Here the chert strikes N. 60° W., dips 50° SW., and is heavily stained with manganese oxides. Near the center of the cut is a 2-foot bed of cherty ore, which lenses out in both directions, and does not appear to extend bej'ond the end of the cut. A 6-inch zone lies along the hanging wall, which consists of cav- ernous oxide ore that contains about 35 percent manganese, but the quantity available is small. The greater part of the bed is manganiferous chert, which probably has less than 20 percent manganese. A 20-foot adit was dug here in 1935 in an effort to follow a stringer of cinnabar in the face of the cut above the manganiferous chert bed, but the adit was begun too high to intersect the bed, and no manganese ore was found. About 500 feet downstream from the first prospect, a small pit 20 feet above the creek exposes thin-bedded red chert interbedded with reddish manganiferous shale. These rocks strike N. 60° W., and dip steeply into a fault contact with sandstone of the Franciscan about 50 feet to the southwest. The ore contains less than 20 percent manganese. On the east side of the creek, opposite the Von Glahn house, a small open cut exposes nearly flat-lying thin-bedded red chert which shows some manganese stains. The ore here contains less than 10 percent man- ganese. Another prospect is located beneath two prominent Digger pines a quarter of a mile N. 62° W. from the Von Glahn house. Here, two open cuts expose highly sheared chert, and possibly some sandstone, with iuterbeds of manganiferous cherty ore. On the surface, the ore may contain from 20 to 30 percent manganese, but the ore that could be obtained by mining would not average over 10 to 20 percent manganese, and would be high in silica. No. 33. Witter Springs Mine. (By E. F. Davis and A. 0. Wood- ford, August 4, 1918.) The Witter Springs mine is owned by the Witter Medical Springs, Inc. Blake Brothers of San Francisco are mining the ore under a contract with the owners. The mine is near the center of the south line of sec. 32, T. 16 N., R. 10 W., and is 2,000 feet northwest of the Witter Springs Hotel, 1,000 feet from the road. Ore is hauled from the mine to the road in sleds and then hauled to Ukiah by auto truck at a cost of $6.00 a ton. The distance from the loading place to Ukiah is 26 miles but it is only 22.5 miles to the nearest railroad crossing. The ore body is a thick bed enclosed in thin-bedded radiolarian chert and shale. The bedding planes of the chert are parallel to the walls of the ore body and where the walls curve due to variation in the thickness of the ore body, the chert bends to conform with this curvature. The chert 100 MANGANESE IN CALIFORNIA [Bllll. 152 along: tlio walls of tlie ore body has been crushed and sheared. The ore body and tlie eiich)sinjj: chert strike in jjeneral N. 30° AV., and dip 55° E. The ore body is exposed over a lenj>th of 30 feet and is cut off at its south end by a fault. It ranj^es in thickness between 4 and 8 feet. The internal structure of the ore body is rather complex as it con- sists of interlayered bands and lenses of different materials. In some places there are gradual transitions between tlie different materials, whereas in otliers the boundaries are abrupt. The.se boundaries are in general parallel to the bedding of the enclosing chert, so the ore bed shows a rude stratification. The ]n-incipal constituent of the ore body is massive jasper. This jasper is mostty cream to yellow in color. Some is black, some brown, and a small amount is red. A little white or gray jasper is also present. The jasper is cut by a complicated network of veinlets of manganese oxide. Generally the cream colored variety shows streaks and small lenses of other colors but though these streaks parallel the bedding, the rock does not part along them. The cream colored variety occurs in lens-like masses within the ore bed. The ore beds have a maximum thickness of 3 feet. Associated with the jasper in the ore bed is a brown manganese ore of a variety which previous tests have shoAvn to consist of a mixture of opal and manganese oxide in a state of oxidation lower than the ordinary black oxides. Along water channels and at exposed surfaces this material becomes changed into a siliceous black oxide of manganese with bright vitreous luster. The brown opaline ore occurs as irregular pockets or as bands in massive chert. The boundary between brown ore and enclosing jasper may be a transitional boundary. The brown ore also is found in thin lenticular beds separated from one another by soft shale partings. Some of these thin beds occur together as a lens-like body within the ore bed. The brown opaline material is generally cut by numerous veinlets of a pale-pink manganiferous carbonate. The ore bed also contains small lenses of thin-bedded red radiolarian chert with red shale partings. These chert beds occur in groups of lenticular beds separated by shale, each group of thin beds forming a lens in the ore bed. Workings consist of an open cut 55 feet long and varying in width from 35 feet at its lower end to 5 feet at the upper end. The lower end of the cut is at an elevation of 40 feet below the upper end. A flat bench was cut into the hill just below the point where the ore is offset by the fault. Here a depth of 10 feet below the surface was attained in the farther end of the cut. The ore above this point is exposed in a cut, the bottom of which parallels the former surface and is nowhere more than G feet below it. The ore is extremely siliceous, not exceeding 20 percent man- ganese, and probably contains only 10 percent. ITnless the ore can be concentrated, it has no value under present market conditions. LOS ANGELES COUNTY No. 1. Bind- Brothers Claim (Amargosa Group, Llewellyn Iron Property). (By Ivan F. Wilson, November 4, 1942.) The Black Brothers claim is on Poi'tal Bidge, 4.3 miles bv road west of Palmdale; it is pro1)ably in the NE] sec. 30, T. 6 N.. R.'l2 W. Palmdale is a rail point on the Southern Pacific Railroad. No claim notice was found on the property, and no one in the vicinity knew the name of the owners. However, the location corresponds to that given on the "Black Brothers" 1950] DESCRIPTION OF DEPOSITS 101 claim in the Bureau of Mines files. This is probably part of the Amar- gosa group of claims of the last war. An old caved shaft and adit on the property presumably dated to World War I, but a bulldozer worked either in 1941 or 1942. This property contains a manganiferous bed of quartzite, probably a metamorphosed chert, enclosed in quartz-mica schist, believed to be the Pelona schist of pre-Cambrian age. Portal Ridge contains a fairly large area of this schist, just north of the San Andreas fault. The manganiferous bed ranges in thickness from 1.5 feet in the northernmo.st cut to 9 feet in the shaft. The average thickness is 3 feet. The ore bed crops out for 165 feet. The maximum depth exposed is 10 feet, in the shaft. The bed strikes N. 20° -45° W., and dips 55° to 65° NE. It is offset by small cross faults. One of these faults in the bottom of the shaft strikes northwest and dips 35° SW., and has a reverse type of displace- ment of 4 feet. The manganese ore consists of partly oxidized rhodonite and spes- sartite scattered among the quartz grains of the quartzite. It is cut by quartz veinlets ranging from a fraction of an inch to 3 inches in thick- ness. The spessartite occurs in yellow brow^n dodecahedral crystals. The rhodonite, which is more abundant, occurs in pink prismatic crystals as much as an inch in length. These minerals in places have been oxidized to hard psilomelane and soft black oxides; here and there patches of cellular silica are stained yellow with limonite. Very little good oxide ore has been found. Most of the black oxidized material still reveals crystal outlines of the original rhodonite or spessartite. The average grade of the bed is about 20 percent manganese. Probably none of the material contains over 35 percent. No. 2. Gladwin and Peet Claim. (Modified from original descrip- tion in California Min. Bur. Bull. 76, p. 38, 1918.) The Gladwin and Peet claim is in sec. 36, T. 6 N., R. 14 W., at an altitude of 4,900 feet, some 2,000 feet above the end of the wagon road in the canyon. It was first located many years ago and was relocated in September 1917 by G. L. Gladwin and H. G. Peet of Los Angeles. The manganese oxides are in small pockets along siliceous outcrops in the schist. The material is siliceous and in general low grade. Two small pockets, only a few feet deep, have been uncovered. Several tons of this low-grade oxide are on the dump. There are several other siliceous outcrops on the claim, but no other manganese outcrops were seen. The deposits are too small to be commercial. No. 3. Purple Sage Group. (By Ivan F. Wilson, October 21, 1942.) The Purple Sage group of claims is in Texas Canyon, a branch of Bouquet Canvon, on the south flank of the Sierra Pelona in the NE^ sec. 7, and SW^ sec. 5, T. 5 N., R. 14 W. The claims were located May 30, 1942, by Clarence Cruzan of Los Angeles. They may be reached by driv- ing 6.5 miles along the Forest Service road up Texas Canyon from its junction wdth Bouquet Canyon. From here one group of outcrops is located 0.5 mile by trail farther up Texas Canyon, and another is located about a mile by trail along a ridge just east of Texas Canyon. The area is covered by thick chaparral. The nearest rail point is 15 miles southwest, at Saugus on the Southern Pacific. The claims are idle, and little develop- ment has been done. On the ridge just east of Texas Canyon is an outcrop of a manganifer- ous banded quartzite (probably a metamorphosed chert) enclosed in 102 MANGANESE IN CALIFORNIA [BuU. 152 quartz-mica schist, which is believed to be the pre-Cambrian Pelona schist. The quartzite is 9 to 10 feet thick where it crops out on top of the ridge, and is said to extend for several hundred feet, although it was not traced by the writer. It stril^es east and dips 60° S. A small shallow open cut has been opened on top of the ridge. The quartzite contains pockets and len.ses of partly oxidized pink rhodonite. In places the rhodonite is coated Avith thin fdms of black man- ganese oxides. Elsewhere pockets and lenses of manganese oxides a few inches to 2 feet thick are present. These oxides are mostly soft pyrolusite, but in part are psilomelane. Both the quartzite and manganese minerals are cut by quartz veins from a fraction of an inch to 3 inches thick. A few of the smaller pockets of manganese oxides may have as much as 40 percent manganese, but most of the material contains considerably less and the general run of the bed would probably not be over 10 per- cent manganese. It would require very careful sorting to obtain any ore of shipping grade. In the bottom of Texas Canyon is an open cut 4 by 4 feet and 8 feet deep on a 2-foot bed of banded quartzite, likewise probably a metachert, cut by quartz veinlets and stained with manganese. A few small pockets of manganese oxides, mixed with considerable quartz are also present. Small garnet crystals occur. Some of the small pockets here may contain 30 jDcrcent manganese, but the general run of the bed is less than 10 per- cent, perhaps less than 5 percent. The quartzite strikes N. 70° E., and dips 70° NW. In the cut the bed is repeated by a sharp drag fold. The bed is said to crop out over a distance of several hundred feet. No. 4. Red Feather (La Frentz) Claim. (By Ivan F. Wilson, October 30, 1942.) The Red Feather claim is on the crest of Portal Ridge west of Palmdale in sec. 24, T. 6 N., R. 13 W. It is reached by driving along the main road west of Palmdale for 5.5 miles, then turning north along a dirt road for 0.9 mile. The total distance from Palmdale, the nearest rail point, is 6.4 miles. The claim was located July 20, 1942, by 11. E. La Frentz and M. M. La Frentz of Palmdale, It has been leased to G. T. Humphreys of Los Angeles. This claim is presumably part of the Amargosa group of World War I, which consisted of nine claims. Another part of the Amargosa group is probably the Black Brothers claim (Los Angeles 1), farther east along Portal Ridge. Production of 168 tons has been reported from the Amargosa group of claims. Judging from the size of the workings, most of this amount probably came from the Red Feather claim. Several old workings are on the property. The manganese ore at this property is found in a series of lenses of quartzite (probably metamorphosed chert) in a coarse-grained quartz- mica schist. This schist is believed to be the pre-Cambrian Pelona schist, which forms a large belt along Portal Ridge just north of the San Andreas fault. The quartzite and manganese ore are cut by quartz veins ranging from a fraction of an inch to 2 feet in thickness. The quartzite lenses are 1 foot to 6 feet thick. The various workings are scattered over a total length of 750 feet, but they are thought to be located upon a series of discontinuous lenses rather than on a continuous bed. The attitudes are variable, the strike ranping from N. 35° W. to N. 55° E., and the dip from 20° N. to 80° S. The average strike is N. 80° W., and the dip is 40° N. Several small cross faults cut the ore beds, one of which strikes N. 15° E., dips 55° E., and has a normal offset of 2.5 feet. 1950] DESCRIPTION OF DEPOSITS 103 The manganese ore consists of partly to completely oxidized pink rhodonite. In places pockets 1 foot to 2 feet thick of fairly pure rhodonite occur ; elsewhere the rhodonite is scattered among the quartz grains of the quartzite. Much of the rhodonite has been incompletely oxidized. However, in places considerable oxide ore has been developed. This oxide ore consists of hard psilomelane and soft black oxide, with patches a frac- tion of an inch to 2 inches in diameter of cellular silica, stained yellow brown by limonite. The best sample of oxide ore contained 31.07 percent manganese. Even in this sample the crystal outlines of the original rhodonite could be seen. Most of the ore contains between 10 and 20 per- cent manganese and much silica. MADERA COUNTY No. 1. Agnew Meadoivs Deposits (Mammoth Lakes). (By Parker D. Trask, September 20, 1941.) The Agnew Meadows deposits are at an altitude of 8,500 feet in the upper part of the canyon of the Middle Fork of the San Joaquin River in unsurveyed land near the center of T. 3 S., R. 26 E. They are situated at the position of the letter "d" in the word "Meadows" at Agnew Meadows in the Mount Lyell topographic sheet. They lie on the east wall of the canyon 200 feet above the bottom of the canyon, 0.8 mile by trail from the dirt road to Mammoth, 10 miles distant. Mammoth is 175 miles by paved highway from Mojave, the nearest rail point. The deposits were located by Charles Summers of Agnew Meadows. Dr. Henrj^ A. Stevens of Los Angeles is considering developing them. The ore bodies are hydrothermal deposits of vein origin. The ore occurs at the intersection of the vertical mineralized zones and schist. Three such zones in a distance of 2,000 feet were seen. The schist strikes N. 30° W. and dips 75° NE. It seems to be a partly recrystallized felsite and is highl}^ impregnated with epidote. The mineralized zones strike N. 40° E. and are essentially vertical. They have a maximum width of 7 feet, but are exposed for only 50 feet. They are covered by talus at the base, but they seem to divided and feather or fade out at the upper end. They are characterized by garnet, some of which is typical skarn, and by pyrite, epidote, rhodonite, rhodochrosite, piedmontite ( ? ) , and a green mineral that weathers to a black manganese oxide ( johaunsenite ?) . The rhodonite seems to be localized mainly in a single stratigraphic zone 2 to 3 feet wide, and the rhodochrosite occurs in a similar zone 2 to 3 feet above the rhodonite. The total width of the manganese deposits is not over 6 feet and the length along the strike in each of the three zones is less than 10 feet. In no locality is the rock completely replaced by manganese minerals. The grade is less than 30 percent manganese. At the northernmost exposure fine-grained hematite was seen in a thin bed just below the manganese zone. No. 2. Hazelton and Kennedy Claim. {Bj N. L. Taliaferro and Theo Crook, June 15, 1918. ) The Hazelton and Kennedy claim was located by J. W. Hazelton and W. C. Kennedy of Madera Countv. It is in sec. 28, T. 9 S., R. 22 E., 12 miles east of O'Neals Post Office, and 35 miles north- east of Madera. It is 3 miles by trail from the nearest road. Development work consists of a small pit 7 feet deep. This pit is on the west side of the canyon of the San Joaquin River 800 feet above the river and at an 104 MANGANESE IX CALIFORNIA [Bull. 152 altitude of 1,800 feet. Lenses of rhodonite-spessartite-quartz rock occur in a quai'tz schist. These lenses are ])arallel to tlie schisto-sity. The belt of schist in wliich the riiodonite rock is found is not over 60 feet wide, being a schist inclusion in a body ol" g:ranite. The manganese rock and the enclos- ing schist liave been tliorouglily nietaniorpliosed by dynamic and contact action. The schist Avas originally a rock composed almost wholly of silica, perhaps chert and siliceous shale. No. 3. Krolin Prospect. (By N. L. Taliaferro and Theo Crook, June 15, 1918.) A manganese claim was located in sec. 22, T. 7 S., R. 21 E., by n. A. Krohn of Coarsegold. It is 4 miles north-northeast of Coarse- gold and 18 miles northeast of Raymond. Development consists of an open cut 12 feet long and 8 feet deep. A few small lenses of partly oxidized rhodonite rock occur in quartz-mica schist, which may be referred to the Calaveras formation. No ore of commercial value has been found and there is no likelihood of any being encountered. Onh' a few pounds of rhodonite rock is in sight. No. 4. Scott Prospect. (From files of U. S. Geological Survey, 1942.) A letter in the files of the U. S. Geological Survey from Wm. A. Vinson of Madera mentions a manganese deposit owned by S. A. Scott of Coarsegold. The location of the deposit is not given. No. 5. Stewart and Nuss (Teaford) Prospect. (By Ivan F. Wil- son, September 25, 1942.) The Stew^art and Nuss prospect is located on the crest of a high ridge known as Thornberry Mountain in sec. 1 or 2, T. 8 S., R. 21 P]. It is 9.4 miles by road east of Coarsegold; 4.3 miles northeast along Highw^ay 41, then 5.1 miles southeast along dirt roads. The nearest shipping point is 28 miles to the southwest at Raymond on the Southern Pacific Railroad. The prospect is owned by George and Otis Teaford of North Fork. It has been leased to Stewart & Nuss, Inc., of Fresno. No ore has been shipped ; and as far as known, the property is now idle. Development consists of cuts on both sides of the ridge. On the north side of the ridge is a cut 87 feet long and 20 feet deep, which extends southward into the hill. This is called the "north cut." A shaft is sunk at the southeast end, 7 by 6 feet and 35 feet deep below the level of the cut ; and 200 feet to the southeast on the south slope of the hill a large cut has been made with a bulldozer. This cut, which is 200 feet long, 50 feet wide, and 30 feet deep, is called the "south cut." The cuts reveal a series of lenses of manganiferous, massive meta- chert which has been recrystallized to a fine-grained and to a coarse- grained graj' and white quartzite. Quartz veins cut the chert. The massive metachert is interbedded with quartz-mica schist which may represent original siliceous shale or impure thin-bedded chert. The beds are 0.5 inch to 1.5 inches thick averaging 1 inch. Both the massive metachert and the enclosing schist are cut by flat dikes of granite. In the north cut one dike 0.5 to 1 foot thick extends nearly horizontally around the east and south walls of the cut, 5 to 9 feet above the floor. From 2 to 6 feet below tliis cut is anothcn- mass of granite which extends 3 feet above the floor of the cut and continues down below the floor. The rock is a highly decomposed white, coar.se-grained biotite granite, close to an alaskite in nature. It contains a little biotite and ortlioclase, altered to kaolin. A similar horizontal granitic dike 2 to 3 feet thick occurs in the south cut. Three pegmatite dikes 4 to 6 inches thick were also noted. 1950] DESCRIPTION OF DEPOSITS 105 The north cut reveals three beds of manganiferous, massive ni eta- chert which from northeast to southwest are 1.5, 4, and 3.5 feet thick respectively. The south cut reveals six beds which from northeast to south- west are 5, 5, 2, 3, 5, and 2 feet thick respectively. As the ridge between the north and south cuts has few outcrops, it is impossible to determine which, if any, of these beds extend between the two cuts, but the interven- ing area contains float and manganiferous metachert. The schist and metachert strike N. 20°-40° W., and dip 35° to 50° SW. This area is mapped on the State geologic map as granite. The schist exposed at the prospect may be a roof pendant in the granite. The rocks have been subjected to contact metamorphism in addition to dynamic metamorphism. The beds of massive metachert contain brown manganese garnet (spessartite) and pink rhodonite scattered among quartz grains. The spessartite is more abundant than the rhodonite and occurs in fairly large dodecahedral crystals. Locally it is found in nests, but more com- monly the grains are disseminated through the quartz of the metachert. The garnet and rhodonite tend to be stained and coated with manganese oxide, and in places there are crusts and small pockets of the oxide. How- ever, hardly anj^ masses of oxide of a minable size were seen. All the oxide material appears to be low grade, and most would probably not exceed 10 percent manganese. The manganiferous ore in this deposit is low grade. Very little oxidized material is present, and even the primary spessartite and rhodonite are low grade, being mixed with much quartz. No tonnage of shipping ore was seen. Some 10,000 tons of spessartite and rhodonite running lass than 10 percent manganese may be present. No. 6. Thorn'berry Prospect. (By Spangler Ricker, 1942.) The Thornberry prospect is in T. 7 or 8 S., R. 21 or 22 E., about 5 miles from the railroad. The owner is S. A. Vaneman. The ore consists of films of manganese oxide in a quartzite bed 20 feet thick. Assays run from 2.1 to 6.3 percent manganese, and 1.4 to 2.2 percent iron oxide. MARIN COUNTY No. 1. Fort Baker Deposit. (Modified slightly from original description in Lawson, A. C, San Francisco folio : U. S. Geol. Survey, Geol. Atlas 193, p. 23, 1914.) A deposit of manganese is exposed in a road cut near Fort Baker in T. 1 S., R. 6 W. It consists of a stratified deposit of hard, clean psilomelane about 18 inches thick, grading off in its upper part into a lean ore consisting of chert and shale highly charged with the black manganese mineral. There is no definite boundary between this lean ore and the normal radiolarian chert, for the proportion of psilomelane decreases till it ceases to color the rock. The thickness of the chert impregnated hj ore above the layer of psilomelane is about 12 feet. This body of ore lies within a few feet of an intrusive contact of ellipsoidal basalt with the chert, the contact plane being parallel to the bedding, and may be traced for 90 feet on the outcrop of the formation, which dips about 40° SW. In several samples taken by D. C. Billick, the psilomelane contains gold not exceeding 40 cents to the ton. No. 2. Knutte Deposit. (From files of U. S. Geological Survey, 1942.) The Knutte deposit is in the NW^ sec. 19, T. 3 N., R. 6 W., east of Novate. It is under lease to L. R. Knutte and is typical of deposits in chert of the Franciscan group. 106 MANGANESE IN CALIFOKNIA [Bull. 152 No. 3. Mailliard Ranch Prospect. (Modified sli^-litly from original description in California Min. Bur. Bull. 76, p. 38, 1918.)"^ On the Mail- liard ranch, 8 miles northwest of San Rafael and 0.5 mile south of Wood- acre Lodjre, probably in sec. 13, T. 2 N., R. 8 W., stains and irrcfiular patches of man<>anese oxide occur in rexl jasper which apparently has been caught up as blocks in serpentine. The material is high in silica and has not been developed. The property is in lot 9, block 33, of a tract owned by the Lagunitas Development Company of San Francisco. No. 4. The Mazza Prospect. (By E. F. Davis and F. S. Hudson, March 3, 1918.) The Mazza prospect is located on the property of R. Mazza, 6.5 miles south of Petaluma. It would lie in the SW| sec. 28, T. 4 N., R. 7 W., if the sections survey was made. Development consists of a pit whose horizontal dimensions are 20 by 20 feet. The ore body lies parallel to the bedding of the enclosing chert and strikes N. 25° E., and dips 60° SE. The hanging wall consists of soft brownish iron-stained chert ; the footwall is covered by alluvium. The ore zone is at least 15 feet thick. The ore minerals consist of a mixture of manganese carbonate and silica. Both gray and pink carbonate are present. Silica seemingly increases toward the footwall of the ore body. The material in the lowest exposed part of the ore zone consists of scattered spherules of carbonate in a gray chalcedonic matrix. The better ore occurs in bunches up to 2 feet in diameter, enclosed in more siliceous material. Numerous quartz veins traverse the ore body. Cubes and irregular masses of pyrite are found locally in the ore. A few specks of cinnabar were seen. Along the hanging wall, a small amount of oxidation has occurred, resulting in black oxide that contains considerable amounts of silica both disseminated within the oxide and in the form of residual cores. Oxidation has also taken place along joints within the ore body. As far as can be judged from the exposed material, no ore here could be profitably extracted. No. 5. Petal uma-Poi7it Reyes Prospect. (By E. F. Davis and F. S. Hudson, March 3, 1918. ) On the north side of the road from Petaluma to Point Reyes, 1 mile south of the Union School in the north center of sec. 30, T. 4 N., R. 7 W., a bed of massive manganese ore crops out. It may be traced on the surface for 40 feet and appears to be at least 3 feet thick. The material in the outcrop consists of black manganese oxide with iron stained spherules of silica. The silica content probably runs from 20 to 35 percent. No. 6. SausaUto Point. (Modified slightly from original descrip- tion in Caliroruia Min. Bur. Bull. 76, p. 39, 1918.) About 1 mile west of Sausalito Point in T. 1 S., R. 6 W., manganese oxides are associated with massive chert. The oxide is mostly of low grade, but one lens of good ore has a thickness of 15 inches and can be traced for 6 feet. No attempt has been made to develop the prospect. MARIPOSA COUNTY No. 1. Caldwell (Daly) Mine. (By Ivan F. Wilson, September 21, 1942.) The Caldwell mine, known as the Daly mine during World War I, is 8.5 miles southwest of Coulterville in the NE:} sec. 14, T. 3 N., R. 15 E. It is reached by proceeding along the road west of Coulterville 6.9 miles to the Granite Springs School, turning south for 1.5 miles, then west through a gate into the Caldwell Ranch. From here a road branches to the right (northwest) for an additional 0.2 mile to the northern 1950] DESCRIPTION OF DEPOSITS 107 workings, and another branches to the left for an additional 0.4 mile to the southern workings. The workings are situated in an area of fairly gentle topography partly covered with manzanita brush. The northern workings extend over two low ridges, across a ravine; the southern workings are near the crest of another ridge to the south. The nearest shipping point is 8 miles by road to the south, at Barrett Station on the Yosemite Valley Railroad. The property is o^vned by Claude C. Caldwell, ]\Iarguerite Caldwell, and John J. Caldwell. It was formerly leased to Gertrude Hickman and Walter Mc Vicar, but is now leased to Walter Hixson of Raymond, Madera County. The property is idle at present. The principal development consists of a shaft inclined 45° south- east, and 57 feet long. From the bottom of this shaft a drift extends 26 feet southwest. A second shaft, 10 feet deep, lies 500 feet south of the main shaft, and a third shaft, 15 feet deep, is 300 feet south of the second shaft. In addition, 30 open cuts of varying sizes have been opened along the ore zone over a distance of more than 1,000 feet. The manganese ore at this property is a bed or series of lenses enclosed in chert. The chert includes thick-bedded to massive red chert, thin-bedded buff to gray chert, and massive to thick-bedded white chert. The chert is enclosed in gray to greenish metatuff and metavolcanics. These beds belong to the Amador Group, and the chert has been named the Hunter Vallej^ chert by Taliaferro. The northern group of workings has followed an ore bed over a total length of 750 feet in a northerly direction — as far north as the inclined shaft. The bed may not be continuous over this length, as it probably is lenticular. The manganese bed and enclosing chert strike on the average N. 5° E. over this distance, but the beds curve from place to place and the strike varies locally from N. 30° W. to N. 45° E. The dip in general is to the east, ranging from 50° to 80°, but in two or three places the dip is 80° to 85° W. Starting 85 feet north of the inclined shaft, a series of cuts follows the chert an additional distance of 320 feet to the northwest. A little manganese ore, mostly low grade, was encountered in these cuts. The strike of the beds in these cuts ranges from N. 25°-50° W., and the dip, 75° E. The southern group of workings is a quarter of a mile south of the northern group, and exposes a manganese ore bed in what is apparently the same belt of chert. These workings cover a length of 170 feet. The chert here is thin-bedded with shale partings and is red, white, and pale green in color. The chert occurs in beds an inch or so thick, separated by shale partings an eighth to a fourth of an inch thick. It contains what appears to be radiolarian remains. There are also bold outcrops of massive red chert. The beds in the southern workings strike north to N, 45° "W., and dip 55° to 75° E. Ore is now exposed mainly in the third shaft at the south end of the northern workings, and in the inclined shaft. It is also exposed in a few of the cuts, but most of these cuts, which date back to World War I, have caved. The third shaft exposes 2 feet of high-grade oxide ore (mostly psilomelane). This bed of oxide seems to split into two parts each about 1 foot thick at the southwest end, separated by a metavolcanic rock resembling a metabreccia. 108 MANGANESE IN CALIFORNIA [Bllll. 152 The inclined shaft reveals 2.5 to 5 feet of ore on the southwest side, which wedpes out toward tlie northeast. This ore is partly oxide ore (mostly psilomelane) but in larg:e part is unoxidized ore, which is a brown to p:ray or rose colored cherty manp'aniferous calcium carbonate (man- panocalcite). Analyses made in 1918 indicated that this material ran 20 to 23 percent manp:anese, 30 to 40 percent silica, and was hig:h in lime, indicating the probable presence of manganocalcite. An exposure about half way down the shaft reveals 2.5 feet of hard, brittle carbonate and psilomelane ore surrounded on each side by 1 foot of soft, black oxide ore. Some psilomelane ore is exposed in the drift at the bottom of the sliaft, but most of the material here is the primary carbonate ore, which is 3 to 4 feet thick. The dump at the inclined shaft contains 10 or 15 tons of carbonate ore which has been discarded. Near the top of the shaft the ore bed is cut by a longitudinal fault, forming a gouge zone, which nearly parallels the ore bed but cuts across it at a slight angle. Some black oxide ore half a foot to 2 feet thick is exposed in cuts south of the inclined shaft. Gray carbonate ore is piled on the dump beside the inclined shaft. About 6 inches of ore is exposed in cuts north of the shaft. In the southern group of workings, up to 2 feet of soft, shaly, black oxide ore is exposed at the southern end of the ore zone. An old dump here contains an estimated 13 tons of rather soft, porous ore, pyrolusite, and botrj^oidal psilomelane, with red iron oxide stains, and white patches of silica. The total past production of this mine is about 250 tons. Part of this was produced during World War I and part was shipped 5 years ago. The ore averaged 45 percent manganese. The 1918 report lists the pro- duction at that time as about 100 tons, averaging 45 percent manganese, 6 percent iron, and 13 percent silica. On the dumps at present are about 15 tons of oxide ore, probably running over 35 percent manganese, and 15 tons of carbonate ore, running 20 percent manganese. A shipment of 9 tons in 1942 ran 49.3 percent manganese, 4.1 percent aluminum, 2.1 percent iron, 0.038 percent phosphorus, 11.3 percent silica, and no zinc. This is one of the largest manganese mines seen in the Sierra Nevada south of Plumas County, from the standpoint of extent of workings, production, and reserves. If the carbonate ore could be utilized, the possibilities of the mine would be greatly increased. No. 2. Donnelly (Carrier) Prospect. (By Ivan F. Wilson, Sep- tember 23, 1942.) The Donnelly prospect, presumably at the same loca- tion as the Carrier prospect of World War I, consists of four claims owned by J. C. Donnelly, probably in sec. 17, T. 4 S., R. 19 E. The prospect is on a steep slope on the west bank of Sweetwater Creek, crossing the road to the Donnelly ranch 0.1 mile south of the ranch house. It is a mile by road north of the Sweetwater Gold mine, and 15 miles northeast of Mariposa. The manganese ore here consists of small pockets, lenses, and stringers of manganese oxides in a massive metachert (fine-grained gray quartzite) cut by gently dipping quartz veins. The metachert is enclosed in gray to yellow sericite schist. The rocks belong to the Calaveras forma- tion. The strike is N. 15° W., and the dip is 70° W. The belt of metachert is 23 feet wide in a gulch below the road, and it crops out at intervals over a distance of 300 feet up the slope above the road, where it is 20 feet wide. The only development is an open cut 300 feet above the road. 1950] DESCRIPTION OF DEPOSITS 109 The pockets and stringers of manganese oxide are mostly too small to be mineable, in general not exceeding 6 inches in thickness. In places are alternating ribs of manganese oxides and silica. The manganese oxide includes psilomelane and pyrolusite. Assays were quoted of 30 percent manganese. No unoxidized ore was seen, but in the similar Strickland prospect (Mariposa 6) to the north, the primary mineral is rhodonite. No. 3. Gale Prospect. (By Ivan F. AVilson, September 22, 1942.) The Gale prospect is in sec. 1, T. 3 S., R. 15 E., 7.3 miles along the road west of Coulterville. It is on property owned by "W. T. Gale of Coulter- ville. The deposit is on a low knoll 200 yards southeast of the Gale ranch house, on the south side of the road. No development for manganese has been done on the property. One old shaft 6 by 6 feet, and 20 feet deep, is said to have been sunk in the eighties. This shaft reveals chert, but no manganese ore. Massive to thick-bedded white, yellow, and pale-red chert is found in the vicinity. These chert beds contain manganese stains, and in one or two places they have stringers of psilomelane up to half an inch thick. The chert strikes north, and dips 70° E. It is probably part of Taliaferro's Hunter Valley chert of the Amador Group, which appears also at the Caldwell mine and at Jasper Point (Kelm prospect, Mariposa 4) on the Merced River. No manganese ore was seen at this prospect. No. 4. Kelm Prospect. (By Ivan F. Wilson, September 24, 1942. ) The Kelm prospect is located at Jasper Point, a station on the Yosemite Valle}^ Railroad, on the south bank of the Merced River (near the Exchequer Reservoir). It is in sec. 19, T. 3 S., R. 16 E. The prospect is on a steep northwest slope on the east side of a ravine 100 yards south of the railroad tracks. There is no road to the prospect, and the labor and equipment have been transported by train. The property was idle when visited. The prospect is owned by Herbert J. Kelm of Raymond and by the Allebrand Minerals Companj^ of San Fernando. Mr. Kelm operated a jasper quarry on the property for a number of years. He did some development work on the manganese prospect in 1941, but no ore has been shipped. In the jasper quarry east of the manganese deposit is chert several hundred feet thick, intercalated with green metatuff and metavolcanic rocks. There are many alternating layers of thick-bedded purplish-red and green chert. The chert has a dip of 35° to 40° E., and a strike of N. 0°-20° W. The manganese prospect is near the base of the chert sec- tion. The chert is underlain by a greenstone or pillow basalt, showing a well developed ellipsoidal pillow structure. This chert has been named hy Taliaferro the Hunter Valley chert member of the Amador Group. The manganese ore consists of a bed or series of lenses enclosed in thick-bedded red chert. It is exposed mainl}^ in an open cut 10 by 8 feet, and 15 feet deep at the face, and hj shallower cuts farther up the slope. This cut exposes a manganiferous bed up to 6 feet thick. The high-grade ore occurs as zones or lenses averaging 1.5 feet thick. These ore zones have sharp boundaries and could easily be separated from the enclosing manganiferous chert. One such lens is exposed in the bottom of the cut ; up the slope are at least two other such zones of high-grade ore. The bed is cut by small transverse faults, and the base of the ore bed is sheared. One prominent fault strikes N. 80° E., and dips 70° S. The chert here has a strike of N. 25° AV., and a dip of 45° NE. The manganiferous body is exposed on the surface for a distance of 35 feet. The surface slope at this point has an inclination of about 35°. 110 MANGANESE IN CALIFORNIA [BuU. 152 Ore crops out in two or three places 50 to 100 feet up the hill from the ore bed just mentioned. These outcrops are at about the same horizon, but there is no evidence of the continuity of the ore between. Between the main cut and these outcrops a tunnel has been cut into the hill for jasper. Tliis tunnel is 30 feet long, bordered by a cut 30 feet long, trend- ing S. 20° E. into the hill. It reveals thick-bedded red chert, striking N. 35° W., and dipping 50° NE. This place is at a horizon a few feet above and northeast of the manganese bed. The chert underlying the ore bed is cut by quartz veins 3 to 4 inches thick. Some of these contain con- siderable quantities of pyrite in cubic cr3^stals, either scattered through the vein or in nests. The ore consists of manganese oxide, in part botryoidal, hard, blue black psilomelane ; and in part soft, black, sooty pyrolusite. No unoxidized manganese minerals were seen. The high-grade lenses of ore probably run 45 to 50 percent manganese. Assays were quoted by Mr. Kelm at 46 to 50 percent manganese, with the other constituents in one assay deter- mined as 1.6 percent iron, 5.8 percent silica, 1.2 percent alumina, and 1 percent zinc. No. 5. Rohie Prospect. (By Ivan F. Wilson, September 20, 1942.) The Robie prospect is 8 miles west of Coulterville in sec. 2, T. 3 S., R. 15 E. It is on the south side of the road running west from Coulterville, 0.8 mile west of Granite Springs School, which is 6.9 miles west of Coulterville. It is on property owned by John L. Robie, Lazy J Ranch, Coulterville. The prospect is on a low ridge southeast of the Robie ranch house. One small pit 4 by 4 feet by 1 foot deep is located on the property. This bit reveals massive to thick-bedded white chert more or less pene- trated by bands and stringers of psilomelane. Most of the material exposed appears to contain about 50 percent silica in the form of white chert, and the manganese content is perhaps 20 to 30 percent. An assay of 30 percent manganese was quoted. This ore is probably about the best that could be obtained from the material exposed here. The bands of psilomelane are too small to be separated from the chert by hand sorting. The prospect is a part of a large belt of chert, mostly white, but some of it is red. It strikes N. 10° W., and dips nearly vertically. This belt probably extends south through the Caldwell mine (Mariposa 1) and the Jasper Point prospect (Mariposa 4) on the Merced River. It is part of the Amador Group of Taliaferro, and was named by him the Hunter Valley chert. No. 6. Strickland {Mehold and Camin) Prospect. (By Ivan F. Wilson, September 23, 1942.) The Strickland prospect, which is prob- ably the same as the Mebold and Camin claim of World AVar I, is in sec. 8, T. 4 S., R. 19 E. It is on the west bank of Sweetwater Creek, 3.2 miles by road north of the Donnelly prospect (Mariposa 2). It is about 16 miles by road, northeast of Mariposa. The jirospect is said to be on patented land owned by Mrs. Anna Strickland of Hollywood. A claim notice, located by Hugh Andrew Mulkern of Santa ]\Ionica, dated April 1, 1942, was seen on the property. Development consists mainly of an irregular shaped cut trending S. 15° E. This cut is 65 feet long, 3 to 15 feet wide, and 3 to 6 feet deep. It reveals a bed of manganiferous massive metachert, recrystallized to fine-grained gray quartzite, 13 feet in maximum thickness, and averag- ing 5 feet. The metachert is cut by quartz veins, and is enclosed in 1950] DESCRIPTION OF DEPOSITS 111 sericite schist. The general strike is N. 60° W., and the dip 75° SW. The rocks belong to the Calaveras formation. In one place the metachert is cut by a porphyry dike 1.5 feet thick. Some smaller shallow cuts farther up the slope, south of the main cut, reveal mostly sericite schist; evi- dently the metachert -wedges out in this direction. Manganese oxides are more or less disseminated through the meta- chert, but the highest-grade ore occurs in pockets and lenses. Some of these lenses reveal high-grade ore containing 45 percent manganese. This high-grade ore is mostly nodular, botryoidal psilomelane and to a minor extent pj'rolusite. Ore of shipping grade which could be separated by hand sorting probably averages 1 foot or 2 feet in thickness over the length of the main cut. The rest of the metachert in this cut contains between 10 and 35 percent manganese. Some patches of pink rhodonite were seen in specimens on the dump, and this is probably the main mineral from which the manganese oxides were derived in this deposit. No. 7. Surprise (M-Q) Claim. (By N. L. Taliaferro, June 22, 1918.) The Surprise claim was located by E. B. Pine of Coulterville. It is in the E| sec. 23, T. 3 S., R. 17 E., 8 miles by road and trail, northeast of Bagby, on the Yosemite Valley Railroad. There are 2 miles of trail and 6 miles of steep mountain road to the railroad. This was formerly known as the M-Q claim. Development consists of a shallow cut on an outcrop of manganese ore on Indian Creek, about 0.2 mile from its junction with the North Fork of the Merced River. Ore is exposed only in the bottom of the gulch. The general country rock is dark blue-gray to black phyllite, con- taining small lenses and layers of quartz schist, or quartzite. The phyllite strikes N. 60-70° W., and is either vertical or has a high dip to the east. These rocks may be referred to as the Calaveras formation. Their exact position in this group is not known but they are near the western edge of what may be the main eastern belt of the Calaveras. Although rocks of the Calaveras have been mapped to the west of this great belt, it is doubtful if any true Calaveras occurs outside of this belt. The ore is associated with one of these beds or lenses of quartz schist. It apparently occurs as lenses within the quartz rock and is parallel to the schistosity of the enclosing rocks. There is no evidence of veining or that the manganese has been secondarily introduced. The unoxidized ore varies considerably in character. The prevailing type is a pink to gray or fawn-colored manganese carbonate-rhodonite with scattered grains of spessartite. The ratio between the manganese car- bonate and the rhodonite varies considerably. In places the ore consists largely of carbonate with scattered grains and crystals of rhodonite ; in. other places it consists largely of rhodonite. In places small yellow to red-brown garnet is common. The garnet crystals are usually coated with a film of manganese oxide and are probably spessartite. The primary ore seems to have been a siliceous manganese carbonate. Dynamic meta- morphism has caused the development of rhodonite and spessartite through the carbonate rock. A partial analysis of a representative sample of primary ore made at the Berkeley Station of the U. S. Bureau of Mines indicated the rock was composed of equal parts of rhodonite and rhodochrosite. The oxidation has been superficial and has extended inward from the surface and along cracks only to a depth of 6 or 8 inches. An analj^sis of carefully selected oxide ore by a commercial 112 MANGANESE IN CALIFORNIA [Bull. 152 analyst reportedly gave the folloAvinp: results: Maujifanese, 41.30 per- cent; iron, 2.80 percent; silica, 8.10 percent; sulphur, .04 percent; and phosphorus pentoxide, .13 percent. MENDOCINO COUNTY No. 1. Ash Hollow Prospect. (By N. L. Taliaferro, October 31, 1917.) The Ash Hollow prospect is on deeded land belonging to W. II. Fitzhugh, and is near the head of Ash Creek. It is 2 miles northeast of Hulls Valley and 14 miles by road north of Covelo in the southwest part of T. 24 N., I\. 12 W. The manganese occurs as veinlets and mirrors in a block of thin-bedded chert and shale included in serpentine and green- stone. The serpentine appears to be later than the greenstone. The chert block is 15 feet long and 7 feet thick. The thin-bedded chert and shale are intensely filmed and mirrored with manganese on every surface and minute crack. This coating of manganese is misleading as it gives the prospector an erroneous idea as to the amount of manganese present. The thicker chert layers are cut by numerous small veins of black manganese oxide. Under the microscope the chert is reddish brown (red in reflected light) due to red iron oxide. Partial crystallization to fibrous chalcedony has begun. Numerous radiolarian remains may be seen, these having been almost wholly crystallized to chalcedony and quartz; and only slight traces of their original structure is left. The chert is veined with calcite, quartz, and black manganese oxide (psilomelane?), all of which are apparently contemporaneous. In the slide examined no trace of any original manganese mineral could be found. All the manganese is apparently secondary. No. 2. Bevins-Busch (Lee, Poiter Valley) Claim. (By E.F.Davis and F. S. Hudson, July 26, 1917.) The Bevins-Busch claims are owned by Bevins and Busch of Potter Valley, and are at present under lease to F. W. Keeney. This group of claims is in sees. 3 and 10, T. 17 N., R. 12 W., 5 miles northwest of Potter Valley Post Office. They lie on the east side of the divide between Redwood and Potter Valleys. The property has pro- duced 200 tons, mostly after 1917. Manganese stains are widely distributed, but development has been confined to four places. On the northwest end of the property a body of massive psilomelane 1.5 to 2 feet wide is exposed in a short tunnel. The ore body strikes N. 70° W., and dips 60° NE. The footwall of the ore body is composed of well-bedded red radiolarian chert the bedding being parallel to the ore body. The hanging wall is of massive chert that has been somewhat brecciated. The second working place is in the central part of the property. Here an ore body 2.5 feet thick has been exposed. The ore consists of masses of hard psilomelane mixed with soft ore, probably pyrolusite. As numerous faults cut the ore body, its relation to the wall rocks is not clear. No work was being done on the No. 3 working at the time of our visit. The fourth working is at the south end of the property. Here a thin seam of poor ore has been exposed in an open cut. The ore body strikes about east and dips 60° S. It ranges in thickness from 1 foot to a mere film. It lies within, and parallel to, well-bedded red chert and shale. On the hanging- wall side the ore is separated from the bedded chert by a 6-foot thickness of massive red and yellow chert, cut by numerous veins of quartz and chalcedony, and by seams of manganese oxide. 1950] DESCRIPTION OF DEPOSITS 113 No. 3. Big Bend Claims. (By N. L. Taliaferro, October 29, 1917.) The Big Bend claims, two in number, arc on the county road 2.5 miles east- northeast of the Covclo Ranger Station and are near the bend in the Middle Fork of the Eel River where the course of the river changes from southwest to west. These two claims are in the NJSW:1 sec. 28, T. 23 N., R. 11 W. The locators are C. V. Brereton, ISl. G. Morrison, J. D. Morrison, and W. E. Shields of Covelo. No development work has been done and no ore is exposed in place. About 0.1 mile south of the county road and on the west side of a low ridge, blocks and fragments of fairly good oxide ore are found for a distance of 250 feet in a northeast direction. The largest blocks are 1 foot in diameter. Red chert is the predominant float rock here. The ore on the surface is porous and consists of psilomelane, pyrolu- site, and dark brown to black earthy mixture of oxides, which for lack of a better name will be called wad. The ore contains a variable amount of silica in the form of secondary quartz veinlets and as residual cores of leached chert. Many of the residual cores and patches of chert are pitted with many small spherical cavities up to 0.4 millimeter in diameter. Since the manganese oxides are seen to be derived from this spherulitic chert, it is safe to assume that the small cavities were once occupied by spherules of manganese carbonate. Another tj'pe of float is seen in which the original manganese ore appears to have occurred in lenses 1 millimeter to 3 millimeters thick, separated by equally thin layers of chert containing many small spherical cavities. These small lenses, now more or less com- pletely replaced by black manganese oxide, may have originally been lenses of manganese carbonate. On the whole the ore seems to have been derived from a chert containing more or less manganese in the form of spherules of manganese carbonate. Therefore, it is probable that com- mercial ore will be found only in the oxidized zone. No. 4. Brereton 3Iine (Michaels, Roman, and Weeks; New Year; Old Countrij Deposits). (By Ivan F. Wilson, July 7, 1942.) The Brereton mine is east of Covelo in sec. 31, T. 23 N., R. 11 W., on the steep north side of the ridge sloping down toward the Middle Fork of the Eel River to the west. It is at an altitude of 2,000 to 2,100 feet, and is 100 to 200 feet above a stream to the north. It is now reached from Covelo by driving 12 miles east to the Eel River Ranger Station, then going back toward the west along the south side of the Middle Fork of the Eel River for 3 miles to the site of the old Covelo Ranger Station. Near here the bridge has washed out. Across the river from here, a road runs up the mountain to the east for about a mile to Capt. Smith's Ranch (Rancho de Manana). The mine is a quarter of a mile by trail east of Capt. Smith's Ranch. The total distance by road from the nearest shipping point at Los Rios on the Northwestern Pacific is 32 miles ; however, if the river could be crossed at the old Covelo Ranger Station, the distance would be reduced to 26 miles. The mine is on property owned by Mrs. J. Q. White of Ukiah. It has not been worked since World War I, when it was operated by C. W. Ilymer and L. E. Rufener of Covelo. Former names for the mine are : New Year, Michaels, Roman and Weeks, and Old Country. The total production is about 150 tons, all during World War I. The ore at the Brereton mine is in faulted bodies of chert striking northeast and dipping northwest. The chert is underlain on the southeast by sandstone. Chert occurs on the ridge southwest of the mine, but sand- 114 MANfiANESE IX CALIl'OKNIA [Bull. 152 stone is the chief rock there, and up the ridge to the southeast. A bed of sandstone at the top of the ridpe strikes N. 35° E., and dips vertically. Down tlie rid^e to the northwest the rock is chiefly diabase and green- stone. Sandstoiie is found below the greenstone. Most of the ore Avas obtained from oi)en cuts and stopes and at least two tunnels in the eastern part of the property. All these workings are caved and the ore is not now exposed, so the relations cannot be deter- mined. However, according to the report by Davis and Woodford given below, the ore occurred in three places separated by faulting, in each l)lace being underlain by thin-bedded red, green, and gray chert, and overlain by thick-bedded gray iron-stained chert and shale. The ore body was said to be 3 feet thick. About 5 tons of high-grade ore is piled on the dump of a caved adit driven into the hill to the south near the east end of the property. The ore is a very high grade gray manganese carbonate, covered by thin films of black manganese oxides. It is cut by veiidets of pink rhodochrosite, and by veinlets of a brown cherty material. This is probably the type of ore which ran 50 percent manganese. Sandstone is exposed at the mouth of this particular tunnel, and the distance to the ore body cannot be deter- mined. A pit 100 feet wTst of the tunnel reveals, on the dump, blocks of coarse-grained sandstone containing shale fragments. One hundred feet southeast of the caved adit mentioned above is a group of cuts or stopes and another caved adit which has been driven into the hill toward the southwest. The dump of this adit contains frag- ments of sandstone, greenstone, and chert. One of the cuts reveals shaly sandstone on the north face, slumped over by hill creep. Loose blocks of massive gray to brown chert, somewhat manganiferous, occur in one of the cuts. Two hundred and fifty feet northwest of the first mentioned adit is a bold outcrop of massive red and white chert, (probably the "massive jasper" described in the 1918 report). A cut into the north face of this outcrop exposes massive red and white chert cut by quartz veinlets and containing manganese oxide stains. Some fault gouge was seen. A cut on the southeast side reveals shale. To the northwest of the massive chert occurs first standstone, then a wide belt of diabase and greenstone, Avith minor amounts of chert. Float ore is said to have been found to the south. Between 350 and 400 feet west of the massive chert outcrop is a caved adit extending 40° E. into the hill. This is probably the tunnel over 200 feet long mentioned in the 1918 report. Greenstone and sandstone are on the dump. Seventy feet west of this caved adit is an irregular shaped pit 30 feet long. Only loose blocks of material are exposed on the sides. On the ground are a few small blocks of high-grade carbonate ore (gray, and brownish gray), cut by veinlets of pink rhodochrosite, and surrounded by fairly thick shells of black oxides. The specimens are very heavy. There are also some heavj' pieces of reddish-brown ore, possibly neotocite, cut by veinlets of rhodochrosite, and altered to black oxides. The pit also con- tains large massive red chert boulders with manganese oxide stains. At the northwest end of the property, 500 feet northwest of the last mentioned adit, is a series of small cuts or pits which do not appear to penetrate the regolith, but reveal loose blocks of manganiferous chert. Some float ore may have been obtained here. 1950] DESCRIPTION OF DEPOSITS ll5 Breret07i Mine. (By E. F. Davis and A. 0. Woodford, August 18, 1918.) The principal ore bodies have been found on the east part of the propei'ty. Here an open cut first exposed a body of carbonate ore. This ore had all been removed at the time of the authors' visit. In the north stope a small body of carbonate ore was found. This ore had also been removed, but the nature of the rocks above and below the ore could be determined. The overlying rocks are shale and a peculiar iron-stained chert. The chert is thick-bedded as compared with ordinar}^ radiolarian chert, occurring in beds 6 to 18 inches thick. Small amounts of iron and manganese in veinlets cut the chert. On fresh fractures the chert is light gray. No radiolaria were seen. The shale alternating with the chert beds is apparently ordinary terrigenous shale. It occurs in beds 4 inches to 1 foot thick. Below the ore body is a bed of thin-bedded red, green, and gray chert between 2 and 3 feet thick. The individual chert beds are from 1 inch to 1.5 inches thick. The shale partings are thin, but in appearance this chert is identical with ordinary radiolarian chert. It contains a few round spots which may be radiolarian skeletons. Underlying the thin-bedded chert are sandstone and shale of the sort common to the Franciscan group. In the central stope a body of gray carbonate ore was exposed. The relations are the same as those just described. Over the ore lies thick- bedded chert with gray shale. Under it is thin-bedded chert, which is separated from the ore b}^ a foot of soft shaly material. The ore is a fine- grained gray carbonate cut by numerous veinlets of pink rhodochrosite which are later than the primary gray carbonate. The rhodochrosite is 3 feet thick and is cut oft' on both sides by faults. The three places in these workings where ore has been encountered appear to be portions of one ore zone displaced by faulting. The hanging wall and f ootwall of the ore are the same in all these places. The ore bodies have shown similar atti- tudes, sti'iking northeast and dipping to the west at angles of about 30°. No. 5. Buck Bidge Prospect. (By E. F. Davis and A. 0. Wood- ford, August 4, 1918.) Charles B. Walsh and B. Mendenhall of Bachelor, Lake County, own the Buck Ridge manganese prospect on Cow Mountain in sec. 17, T. 15 N., R. 11 W. It is described in the location notice as being on the south side of Cow Mountain about three-quarters of a mile west of Bald Knob near the Lake County line. No. 6. Callizo Prospect. (By Frank S. Simons, May 1942.) The Callizo prospect is in sec. 33, T. 13 N., R. 12 W., 7 miles southwest of Hopland, on the property of Salvador Callizo of Hopland. The prospect is half a mile from a good road, on the crest of the ridge south of Mr. Callizo 's ranch house. The prospect is now owned by S. V. Froiue of Hopland. The ridge is composed of thin-bedded red chert striking about N. 30° W. A small cut exposes a 6-foot bed of manganiferous brown chert, which can be traced intermittently for 100 feet up the ridge. The ore is a dull brown siliceous rock, oxidized on fracture surfaces, the oxide usually being no more than a thin film. The ore bed is at least 6 feet thick in the cut, and the total thickness is nowhere exposed, but outcrops farther up the ridge appear to be very siliceous. The best ore seen, in the open cut, contains about 35 percent manga- nese and a large amount of silica. The average ore has perhaps 25 to 30 percent manganese. The ore farther up the ridge appears to be \evj low in grade, mostly less than 10 percent manganese. 116 MANGANESE IN CALIFORNIA [Bull. 152 No. 7. Cinco de Mayo Claims. (By N. L. Taliaferro, October 26, 1917.) The Cinco de Mayo claims are in sec. 27, T. 24 N., R. 11 W., on the face of the cliff above Blands Cove. They are situated N. 65° W. from D. D. McLauj2:hlin 's cabin. The locators are C. V. Brereton, M. G. Morrison, and W. R. Poster of Covelo. Several hundred feet up on the cliff, which here trends N. 50° E., is an outcrop of highly contorted thin-bedded cliert containin -;i-i >V Figure 2 Geologic map and section of tlie Foster Mountain mine, Mendocino County, California. 1950] DESCRIPTION OP DEPOSITS 123 The primary ore in the main ore body is a massive, dense black mix- ture of a manganese mineral and silica. This mineral resembles braunite from the Fort Seward mine. The average grade of this material is 40 to 45 percent manganese. No. 17. Graham Prospect. (By Spangler Kicker, 1942.) The Gra- ham prospect is in T. 20 N., R. 14 W., 3 miles south of P^'arley. It is said to be owned by Mrs. Vollie Graham of Ilopland. The deposit consists of a small knob of ore, a sample of which assayed 38 percent manganese, 1.09 percent iron, and 36.28 percent silica. No. 18. Hale Prospect. (By Frank S. Simons, May 21, 1942.) The Hale prospect is in sec. 24, T. 12 N., R. 11 ~\V., about 1 mile east of the Shaw and Matthews mine (]\Iendocino 47), and is on land owned by Mrs. Fred Hale of Cloverdale. The property has been idle since 1918. It is 1 mile from the road to the Shaw and Matthews mine, and 8 miles from Cloverdale on the Northwestern Pacific Railroad. A band of thin-bedded red and brown chert can be traced more or less continuous^ for 400 feet in a general north direction. At the north end of the outcrops a short tunnel and drift expose an irregular bed of manganiferous brown and white chert striking N. 30° W., with variable dip to the southwest. The best of the exposed ore contains less than 20 per- cent manganese ; it is high in iron and silica. An open cut 20 feet in length is 200 feet south of the tunnel along the strike of thin-bedded red chert. A small amount of porous red chert with manganese films on various surfaces is piled on the dump. Two hun- dred feet farther south a short tunnel exposes 5 feet of manganiferous brown chert. The best ore seen was probably not over 25 percent man- ganese, principally brown manganiferous opal (neotocite), oxidized near the surface. Five tons of this brown ore is piled on the dump. Fifty feet south of this tunnel an open cut exposes a dip slope of red chert, with the manganese-bearing bed 2 feet thick and very near the surface of the ground. West of the cut the slope of the ground steepens and the ore bed has been eroded away. No. 19. Harms Prospect. (By Ivan F. Wilson, June 8, 1942.) A prospect belonging to Henry Harms of Willits is about 1 mile north of the Foster Mountain mine (Mendocino 16), which is 16.4 miles east of Willits. The prospect is in sec. 34, T. 19 N., R. 12 W. It is reached by a poor road extending southeast beyond the Foster Mountain mine toward the Lazy Moon Ranch, then branching north for a total distance of 2.5 miles. A better road is being constructed northwest of the Foster Moun- tain mine. When this road is finished, the distance from Willits wuU be 17 miles by fairly good road. The prospect is in a chert lens exposed for a length of 130 feet and width of 30 to 40 feet. The chert, together with 20 to 30 feet of overlying sandstone and shale, is surrounded by greenstone. It forms a resistant knob on the crest of a ridge trending southwest, and is fairly- well exposed. The chert is intricately broken by small faults with displacements rang- ing from 2 inches to 15 feet. Most of these faults trend northeast across the strike of the chert, and dip northwest. The chert itself strikes N. 30°- 35° W., and dips 40° to 55° NE. into the slope. The faults have a gen- eral relative horizontal displacement of southwest on the northwest side. Assuming the movement to have been vertical, the faults would be normal faults ; however, the movement may have been horizontal or oblique. 124 MANGANESE IN CALIFORNIA [Bull. 152 No exposures , gs -rwcn- ssh Well-bedded white and buff chert Massive white chert Well-bedded red and white chert Fine-grained sandstone, sandy shole and shale Siliceous manganese ore High-grade block oxide ore , ._ . , 'W^,^^ 5 10 15 20 Feet KujiiKB ■"!. Map of the Harms Prospect, Mendocino County, California. Geology by I. F. Wilson, 19.',2. 1950] DESCRIPTION OF DEPOSITS 125 Tavo separate ore bodies are interbedded in the chert. Both are beds of rather siliceous ore, overlain diseontinuously by a thin zone of high- grade black oxide ore. The lower zone is the larger, being exposed discon- tiniionsly for a length of 130 feet. It is commonly displaced by faulting, along with the surrounding chert (fig. 3). The main part of this bed is a siliceous black oxide ore, containing much white and red chert. Some of it is merely a manganiferous chert. It is estimated that this bed aver- ages 15 to 30 percent manganese, although higher-grade material could be obtained by sorting. The bed ranges in width from 18 inches to 4 feet, averaging about 3 feet. It is overlain over a considerable part of its length by a thin belt of high-grade black oxide ore. This belt is 2 to 6 inches thick, averaging about 4 inches. The ore is in general fairly soft, prob- abl}^ consisting mainly of pyrolusite with some psilomelane and possibly other oxides. It appears to contain very little silica, and the manganese content is estimated to average 45 percent. An upper zone consists of 2.5 feet of siliceous ore probably averag- ing 15 to 30 percent manganese overlain by a few local lenses 1 inch to 6 inches wide, of high-grade black oxide ore similar to that described above. This ore body is exposed for a distance of 35 feet. Development at present consists of two cuts 15 and 30 feet long at right angles to the strike, two other cuts 12 and 30 feet long extending along the southeast ends of the two ore bodies, and smaller shallow pits and cuts along various parts of the ore beds. No. 20. Heughes (Frederica) Prospect. (By B. F. Davis and A. 0. Woodford, August 8, 1918.) Showings of manganese occur on the land of Mrs. Effie M. Heughes of Calpella, in the NEiSEi sec. 27, T. 17 N., R. 12 W. The prospect lies 4 miles by road from Redwood Station on the Northwestern Pacific Railroad. The property has been leased to A. S. Heughes of San Francisco. The Noble Electric Steel Company opened a T-shaped cut having a total horizontal extent of 30 feet. The rocks exposed are considerably fractured. A thick lens of massive chert varying in color from yellow to red was exposed in the working. This lens is cut by numerous veinlets of black manganese oxide and contains small pockets of black oxide ore. No material is exposed here that would pay for shipment. No. 21. Hinrichs Properhj. (By F. S. Hudson and N. L. Talia- ferro, October 16, 1917.) The Hinrichs property is in the SWi sec. 22, T. 19 N., R. 12 W., on the north end of Foster Mountain on land owned by A. Hinrichs. In the northern part of the property, at an altitude of about 2,100 feet, blocks of manganiferous chert have been taken from the red soil. The exterior of many of the blocks has been altered to good manganese ore. About ten tons of ore of fairly low silica, but high iron content, have been mined and sacked. A shaft and trenches have failed to uncover the ore in place. The blocks apparently have come from higher up on the ridge, and a trench to bed rock, started up the ridge, should uncover the ore bed within a short distance. The large size and angular outline of the blocks show that they could not have traveled far. An anal^'sis of an average sample is said to have run 19.5 percent manganese and 11 percent silica. A second working is located on the main ridge at Foster Mountain, at an altitude of about 2,475 feet. It is 100 yards south of a point where the road crosses a saddle on the ridge. Here large boulders of chert, carrying a small amount of low-grade manganese ore lie in soil. 126 MANGANESE IN CALIFORNIA [Bull. 152 No. 22. Hopper Prospect. (By E. F. Davis and F. S. Hudson, July 27, 1917.) The Hopper prospect is 1 mile east of Potter Valley Post Office in the south center of sec. 16, T. 17 N., R. 11 W. ]\Ianganese ore occurs here in a block of chert which has been included in an intrusive body of greenstone of the Franciscan group. The chert has been meta- morphosed by the action of the intrusive rock and has become massive, taking on brilliant vermilion and orange colors. In places a spherulitic structure has been developed. The manganese oxide occurs as veinlets cutting this altered chert, and in a few places the veinlets expand pro- ducing a small amount of siliceous ore. No. 23. Impassable Rock Dejjosit (Rhodochrosite, Mount Sanhe- (Irin). (By Frank S. Simons and Ivan F. Wilson, May 1942.) The Impassable Kock manganese deposit is in the SW| sec. 31, T. 20 N., R. 11 W., and the NE-1 sec. 6, T. 19 N., R. 11 W. It is on the southwest side of Impassable Rock, about 3 miles hy trail from Rackout Spring, which is 27 miles from Willets, the nearest railroad point. The owners are said to be 0. Haslett, L. Winchel, and 0. M. Woodward. Three small ore bodies lie in the face of Impassable Rock. One of these consists of a small block of high-grade slightly oxidized carbonate ore that appears to have been faulted into its present position. The other two ore bodies are seen, on close examination, to consist of heavily stained chert. The relationships of these ore bodies are obscure because of com- plex faulting and intrusion of greenstone in the vicinity. The ore bodies however are small. Numerous blocks of siliceous ore litter the talus slope at the base of Impassable Rock. Just below the talus slope a small amount of carbonate ore is exposed in an open cut, and 50 feet northwest of this cut a block of carbonate ore is exposed in a low cliff face. No rock crops out between the two bodies of carbonate, but the ore is probably not continuous, as all the rock exposed shows considerable faulting. Blocks of the carbonate ore are found in the talus slope beneath the open cut. The ore is light-gray carbonate, cut by small veins of rhodochrosite. The total amount of ore in sight is small, and most of the ore, espe- cially the oxide ore, is of low grade. The prospects of developing a large body of oxide ore in the face of Impassable Rock are slight, as the small amount of carbonate ore below the upper talus slope indicates that no large amount of this ore will be found. No. 24. Jumpoff Claims. (By Frank S. Simons, May 25, 1942.) The Jumpoff claims are in sec. 32, T. 23 N., R. 10 W., on government land. The claim was recently relocated by Elmer Bauer of Covelo. The road from Covelo to Willows runs within 600 feet of the deposit. The Jumpoff deposit was described by Davis and Woodford in August, 1918. A short tunnel has been driven under the exposed ore to cut it at depth, but no ore was found. The deposit appears to be a small fault block of ore com- pletely separated from the parent ore body and containing not more than 50 tons of ore, of about 45 percent manganese. The countrj'^ rock is badly faulted, and any effort to find the main ore body would be expensive. No. 25. Knight Prospect. (By Ivan F. Wilson, July 11, 1942.) A prospect owned by Mrs. Mamie C. Knight, Sunny Brook Ranch, Wil- lits, is 3 miles southwest of Willits, probably in sec. 30, T. 18 N., R. 13 W., or sec. 25, T. 18 N., R. 14 W. It may be reached by driving along the highway south of Willits for 2 miles, then turning west just before reaching the Sunny Brook Ranch. One proceeds along this road to the 1950] DESCRIPTION OF DEPOSITS 127 west for 0.7 mile where an old wagon road turns to the northwest, crossing Baechtel Creek. The prospect is 0.8 mile west along this wagon road, now impassable to automobiles, on top of a hill at an altitude of about 1,850 feet. The only development at this prospect is a small pit on the top of the hill. In this pit siliceous oxide ore is exposed. The best material is soft and punky, containing yellow cores of silica averaging perhaps 35 percent manganese. Most of the material now exposed contains large amounts of white chert, and probably contains 10 to 20 percent man- ganese. The ore bed is 2 or 3 feet wide. The attitude in the pit could not be determined. However, 20 to 30 feet west are some large outcrops of massive to thick-bedded white chert which strike N. 70° E., and dip 60° NW. No. 26. Leap Prospects. (By E. F. Davis and A. 0. Woodford, August 24, 1918.) H. Leap of Laytonville has several manganese pros- pects on his property in the northern part of sec. 11, T. 22 N., R. 15 W., 20 miles from Longvale by road. The workings consist of three small pits sunk on manganese-stained outcrops. The manganese occurs in association with iron oxide in schist. The nature of the schist varies from bright green to a typical blue giaucophane schist. At places in this schist are layers containing large amounts of iron in the form of specular hematite. The flakes of specular iron are parallel, giving a schistose structure to the ore. Some of this schistose iron ore contains bands and streaks of quartz and giaucophane. A few small bodies of nearly pure psilomelane are present but they are of no importance since none con- tains more than a few ounces of manganese ore. A sample of ore con- tained 10.9 percent manganese, 43.5 percent iron, and 32.3 percent silica. No. 27. Leach Lake Mountain (Line Gulch) Claims. (By N. L. Taliaferro, October 26, 1917.) C. V. Brereton and M. G. Morrison have a claim on Leach Lake Mountain and one on Line Gulch on the northwest side of the mountain, probably in sec. 16 or 21, T. 24 N., R. 11 W. These claims were not visited, but a specimen of the ore from the Line Gulch claim was obtained from Mr. Morrison. This is a very good grade of gray carbonate ore similar to that from the Cinco de Mayo (Mendocino 7) claims. No development work has been done on either of these claims. No. 28. Leona Deposit. (From files of U. S. Geological Survey, 1918.) The Leona deposit, in the NE^ sec. 27, T. 17 N., R. 12 W., a short distance south of the Thomas mine (Mendocino 55) is owned by J. L. Taylor et al. of Ukiah and is leased to the Noble Electric Steel Company. Production of 100 tons of manganese ore has been recorded. No. 29. Liberty Claim. (By E. F. Davis and F. S. Hudson, July 26, 1917.) The Liberty claim was located by F. W. Keeney and lies in the SW^ sec. 15, T. 17 N., R. 12 W. The discovery monument is situated on a prominent mass of radiolarian chert, known as "Black Rock." The chert is red in color, has numerous shale partings, and is cut by small fissures filled with manganese oxide. No ore body is apparent here and no work has been done. No. 30. Li7iser Mine. (By Max D. Crittenden, Jr., August 15, 1944.) The Linser mine is in sec. 32, T. 5 S., R. 5 E., 11.6 miles by airline southeast of Garberville. The property is owned by Chester Linser, and operated by Rae F. Helmke of Garberville. The property has been worked entirely by open cut methods, using a large bulldozer for stripping overburden, and exposing the ore bed. A small bulldozer was used to haul 128 MANGANESE IX CALIFORNIA [Bull. 152 ore from the workin y///M LONGITUDINAL SECTION OF TUNNELS 25 50 FEET 1 1 1 1 1 1 .1 Figure 4. Vertical sections of the Big Reef deposit, San Bernardino County, California. Geology by I. F. Wilson. 19^3. 1950] DESCRIPTION OF DEPOSITS 191 below the surface. It is judged that the limiting depth of ore of the type occurring at the surface is about 25 feet in this particular deposit. The manganese oxide is mostly of the psilomelane type, black and hard, possessing botryoidal and concentric structures. There is also a con- siderable amount of a soft, black crystalline mineral with a black streak, which is possibly pyrolusite. This mineral lines vugs and occurs in eon- centric forms. A fibrous dark-gray or black mineral is also present, along with impure soft black oxide. Typical samples had the following composition : Lower tunnel Upper tunnel (percent) (percent) Mn 32.97 35.70 Fe 1.29 1.78 SiOz 17.85 19.07 About 1,000 feet north of the tunnels another ore zone is exposed in open cuts. This zone is along the line of strike of the fissure at the tunnels, but the ore body cannot be traced between the tunnels and open cuts. Several fault surfaces are exposed in the intervening distance. An ore zone 2 to 5 feet wide is exposed in two open cuts, one 62 feet long and 8 feet deep, and the other, 50 feet farther north, 25 feet long. This ore zone consists of veinlets of psilomelane and a fibrous manganese oxide sur- rounding fragments of andesite. The individual veinlets range from a fraction of an inch to 5 inches in thickness. The wall rock is so thick that it would probably not be economicalh^ feasible to mine this type of material. The economic possibilities of the mine would seem to lie chiefly in the possibility of utilization of ore containing less than 35 percent manganese. No. 3. Black Beauty Deposits. (By Ivan F. Wilson, October 31, 1942.) The Black Beauty group of claims, Nos. 1, 2, 3, 4, and 5, is in the Granite Mountains, east of the road between Barstow and Death Valley, in T. 15 N., R. 6 E. The location notices give the location as 14 miles south- west of Silver Lake, 20 miles southeast of Cave Springs, and 9 miles east of the sign on the Barstow-Cave Springs road which reads 56 miles to Barstow. The total distance to Barstow is 65 miles. The claims were located June 19, 1940, by R. A. Koontz of Anaheim ; W. H. Kimball, Jr., of Seal Beach; and H. E. Ellis (deceased). The interests of the locators are handled by Newton E. Anderson, Attorney, of Los Angeles. A small amount of development was done on the claims in 1940. Since the claims were located, the property has been included in the Mojave Anti- Aircraft Range of the U. S. Army. The attempted visit of the writer was prevented by firing on the range. No. 4. Black Mountain (Oallagher) Claims. (By R. R, Morse, September 25, 1918.) A few small outcrops of manganese ore occurring on the Black Mountain claims are scattered over several copper claims situated 8 to 10 miles northwest of Needles, on the southern slopes of the Dead Mountains, in what is sometimes locally referred to as the Ibex Mining district. The claims are in sees. 17 and 20, T. 10 N., R. 22 E., comprising an area of 930 acres. The distance to Java Station, the nearest railway point, is 2 to 4 miles. The Colorado River passes 4 to 5 miles east of the claims. The altitude in the vicinity of the outcrops varies from 1,000 to 1,500 feet above sea level, the lowest being about 100 feet above 192 MANGANESE IN CALIFORNIA [BulL 152 the siding at Java. The claims may be reached from the latter point by crossing a sandy flood plain known as Sacramento Wash. No water or timber is to be had from points nearer than Needles or the Colorado River. These claims were originally located as a copper prospect. Several pits and a 30-foot shaft exposed faint copper stains. Several small dis- continuous bunches of manganese ore were discovered after a severe rain- storm in the spring of 1918. Since this event, the present owners, T. E. Gallagher and J. W. Arrington of Needles, have removed a few hundred pounds of the ore and have opened several pockets not previously exposed. The ore occurs in small scattered lens-shaped bodies in granodiorite gneiss. So far as determinable from present outcrops these ore bodies are discontinuous and follow no apparent structural feature. The bunches of ore are generally less than 10 feet long, and 6 inches to 3 feet wide. Wherever prospected sufficiently the bodies have been found to extend but a few feet in depth. The contact with the gneiss is sharp, the ore generally being encased in a thin selvedge of cream-colored lime car- bonate. The gneiss ranges from coarse-banded porphyritic augen gneiss to finer gneissic granite porphyry. Typical augen gneiss is of common occurrence, the augen consisting of quartz and feldspar, both orthoclase and oligoclase, surrounded by wavy layers of darker ferromagnesian minerals, chief of which is biotite. From the similarity to published descriptions of gneiss occurring in nearby districts, these rocks are probably pre-Cambrian. The ore is chiefly psilomelane with calcite. The psilomelane shows a strong tendency to develop concentric structures in which thin layers of dull sooty oxide alternate with wider bands of steel-blue psilomelane. Many thin bands of red iron oxide also are present. Locally in the massive areas of psilomelane is a faint spherulitic structure which is believed to be due to minute aggregates of crystalline pyrolusite. The ore is of a homogeneous character. It is hard and breaks out readily from the enclosing gneiss. A characteristic sample gave the fol- lowing analysis: manganese, 40.2 percent; silica, 7.9 percent; ferric oxide, 8.4 percent; pliosi)horus, trace. A second sample taken from a small lens cropping out 1 mile distant from that represented by the above analysis gave the following results: manganese, 39.43 percent; iron, 6.96 percent ; calcium, 12 percent ; phosphorus, trace ; insoluble, 1.30 percent. From the appearance of the ore of the various small bodies now exposed, it is probable that an average analysis would run about as follows : Estimated composition averafje ore Percent Mn : 35 FeoOa 5 to 15 CaCO., 15to25 SiOo 5 to 15 No. 5. Black Prince Group (Manganese Cliff, Manganese King). (Modified slightly from original description in California Min. Bur. Bull. 76, p. 61, 1918.) The Black Prince holdings consist of four claims on the 1950] DESCRIPTION OF DEPOSITS 19;{ north slope of the Avawatz Mountains in sees. 4 and 5, T. 17 N., R. 4 E., about 35 miles west of Riggs Station, on the Tonopah and Tidewater Railroad. Massive iron-stained outcrops of breeciated andesite strike east and are cut by a series of small veins of manganese oxide. The silica content of these veins is high. Tlie claims are owned by C. S. Van Horn and C. E. Burckhardt of Daggett. No. 6. Black Raven (Lonkin) Prospect. (By R. R. Morse, Sep- tember 21, 1918.) The Black Raven prospect consists of three lode claims in the volcanic rocks on the north face of Newberry Mountain, about 1 mile south of the railwa^^ station in sec. 4, T. 8 N., R. 3 B. The locator and present owner is Hans von Lankin of Wagner, San Bernardino County. Newberry Mountain presents the usual bare and rugged aspects common to the ranges of the desert, rising abruptly from the arid plain without transitional slopes. The north half of the mountain consists of red weathering rh3'olitic flows and agglomerates, forming extremely resistant and rugged outcrops, at the basis of which steep aprons of loose angular talus make approach difficult. The volcanies are frequently cut by small veinlets of calcite and less often by veins a few inches in width in which the calcite commonly takes the form of dog-tooth spar. A few veinlets consisting of chalcedony and opal in places banded with iron and manga- nese oxides, follow irregular courses across the volcanies. The claims were located to include a belt of conspicuous outcrops in which coarse- and fine-grained calcite, chalcedony, and opal, with varying amounts of massive psilomelane, occur in a shattered zone along an east west line of faulting, cutting rhyolite agglomerate. This zone appears prominently 1,000 feet up the mountainside above the highway, in the vicinity of the Lankin well. From this point the zone ra&j be traced westward for 1,500 feet to an altitude of about 500 feet above the desert plain. The shear zone, partly occupied b,y the introduced minerals, ranges in width from a few feet to 50 feet. On the south it is generally limited by a sharp slickensided M'all of hard deep-red agglomerate. On the north the limits of the zone are less definite ; rhyolite and rhyolite agglomerate occur in the form of firmly cemented breccia and in shattered or sheeted layers for many feet out from the hard agglomerate wall. Beyond this zone to the north are gray rhyolitic ash and fine agglomerate. The deep-red agglomerate is composed of unsorted coarse and fine angular fragments of gray rhyolite in an ashy matrix stained red by an abundance of finely disseminated iron oxide. The lighter-colored agglom- erate to the north of the shear zone lacks the iron-stained matrix and coarser fragments of rhyolite so characteristic of the agglomerate south of the zone. The constituent fragments are pinkish orthoclase, quartz, and rhyolite, generally less than one-tenth of an inch in diameter, and the matrix is extremely fine rhyolitic ash. Within this sheared zone occur stringers and wider veins of black calcite, with thin selvedges and a few narrow irregular bodies of psilome- lane and a minor amount of intermixed calcite. These calcite veins vary in width from a few inches to 14 feet. They are broken b}^ thin bands and irregular included blocks of sheared rhyolite agglomerate. The included psilomelane masses are never more than a few inches in width. Though the calcite filling is traceable practically continuously along the shear zone, the psilomelane bodies occur in the calcite as isolated discontinuous masses or shoots of but a few feet in length. 7 — 11208 194 MANGANESE IN CALIFORNIA [Bull. 152 The calcite is coarsely crystalline, occurring both as bands of long slender needles, arranged at right angles to the walls, and as stocky rhombohedrons. It appears jet black to the eye, but under the microscope the fragments are seen to consist of colorless calcite within which are scattered finely disseminated and larger aggregates of black manganese oxide. Small amounts of fault breccia ore consist of angular agglomerate fragments cemented by calcite and psilomelane. The rocks gradually become less shattered west of the fault zone, and the ore body narrows in width, until at the west end of the claims it is represented only by a thin vein, 1 foot to 3 feet in width, consisting of light and dark banded chalcedony and opal. A center band 2 to 6 inches in width consists of an intimate mixture of manganese oxide and calcite. No. 7. Black Stone Deposit. (Modified slightly from original description in California Min. Bur. Kept. 17, p. 354, 1921.) The Black Stone deposit is 3 miles southeast of Afton, a station on the Salt Lake Railroad in sec. 28, T. 11 N., R. 6 E. on a ridge east of the Mojave River at an altitude of 2,600 feet. A series of lenses of manganese are on the contact between granite and limestone, throughout a distance of 1,000 feet. The strike of the contact is north and south, and the dip is 70° E. The largest lens is 50 feet in length and 8 to 10 feet wide. The mangani- ferous zone can be traced for a mile, and at intervals shows from 8 inches to 4 feet of ore. Manganese occurs in form of psilomelane with a small amount of pyrolusite. The property is undeveloped. The owner is J. H. Massen of Yernio. No. 8. Dawson Deposit (McDowell, Black Chief). (By Ivan F. Wil- son, March 21, 1943.) Some undeveloped claims located by E. W. McDow- ell in World War I have been relocated under the name of Black Chief by J. II. Dawson of Parker Dam. The claims are half a mile west of Lake Ilavasu, 2 miles by boat northwest of the Dawson boat landing. This boat landing is at a point opposite the Thompson mine on the Arizona side of the lake and is near the Orchard deposits (San Bernardino 16). The boat landing is 14 miles northwest of Parker Dam and 30 miles from Parker, Arizona. The deposit is probably in sec. 32 or 33, T. 4 N., R. 26 E. It is in the lower end of what was known as Little Chamehueve Valley, before this was flooded by Lake Ilavasu. The deposit consists of stringers of manganese oxide filling fissures in a flow of vesicular and amygdaloidal basalt. The basalt is 100 feet wide and may be traced for perhaps 500 yards. It strikes east and dips 30° S. On the north it is in fault contact with granite. On the south it is overlain by brown sandstone which has a similar strike and dip. A trans- verse fault brings granite against the sandstone to the west, and another transverse fault was noted farther east along the northern granite belt. Gray limestone is interbedded with the sandstone farther east, and a copper prospect that contains chrysocolla and is said to carry gold, occurs in the limestone. The stringers of manganese oxide strike north, ranging from N. 10° W. to N. 10° E. and stand vertically or dip steeply to the west or east. A series of a dozen or so stringers ranging from 1 inch to 4 inches in thickness was seen over a distance of several hundred feet. The stringers may be traced for a few feet to 50 feet along the length. All terminate against the granite to the north. A few smaller stringers strik- 1950] DESCRIPTION OF DEPOSITS 195 ing east, branch off, but all of the major ones strike north. The stringers consist mainly of banded psilomelane accompanied by soft black oxide. In a few places a dark-gray crystalline oxide was noted. The manganese is accompanied by calcite and in some places by hematite. The larger veins contain brecciated fragments of wall rock. One vein carries narrow bands of chalcedony along its borders. Another vein widens to a thickness of 1 foot for a short distance, and two others reached a thickness of 6 inches. These seem to contain greater amounts of wall rock and of hematite than the smaller stringers, although it is likely that they would run around 35 percent manganese. No. 9. Emma (Black Magic) Deposit. (By C. B. Hunt and Edgar Bowles, 1942.) The Emma or Black Magic deposit is located in sec. 16, T. 18 N., R. 3 E., in the Owlshead Mountains 35 miles from the railroad. The owners are S. F. Brock, John Rayburn, and J. W. Hilliard. The property is leased to Harry Nasland and associates of Beverly Hills. The deposit is a typical fissure deposit. It consists of a mixture of hard and sooty manganese oxides in a breccia of limestone and granite. The man- ganese is found in pockets containing at most only a few tons of ore. It is estimated that at least 10 tons of waste must be removed for each ton of ore. The brecciated limestone and granite belong to the Virgin Spring phase of the Amargosa chaos. The deposit is a few miles north of the Garlock fault. Development consists of an inclined shaft 40 feet in depth. Production up to the time the property was visited in 1942 was 302 tons, averaging 34.8 percent manganese. No. 10. Lee Yim Deposit (Garringer, Lavic Mountain, Manganese 1-10). (By Ivan F. Wilson, March 28, 1943.) The Lee Yim deposit is 5 miles northwest of Ludlow in T. 8 N., R. 7 E. It is reached by proceeding along the highway west of Ludlow for 0.5 mile, then turning northwest along a dirt road for 4.4 miles. The mine lies 0.3 mile east of the end of the road up a steep slope. During World War I a rail tramway went up this slope. The manganese deposits are scattered over an east-west length of 1,500 feet on the surface of gentle relief bordered by steep slopes to the northeast and southwest. These scarps probably are fault scarps. The surface is on a spur running southeast from the Cady Mountains. Ten claims have been located, called Manganese Nos. 1 to 10. They are owned by A. N. Rabe and L. W. Yim. The mine was leased March 10, 1942, to J. M. Elmer and Walter W. Johnson of the Gold Hill Dredging Company, San Francisco. During World War I this mine was known as the Garringer mine. It has also been known as the Lavic Mountain deposit. Production during World War I is recorded as 100 tons containing 38 percent manganese, 1 percent iron, and 10 percent silica. Some develop- ment was done during 1942, but no ore was shipped, so far as known. Previous development consists of 17 open cuts, and one shaft 42 feet deep near the west end of the main zone. The shaft is inclined 70° SW. From the bottom a drift was run 35 feet S. 80° W. Another drift was run to the east about 10 feet. At a depth of 25 feet down the shaft a drift extends S. 10° W. for 10 feet. The deposit consists of three brecciated zones 250 feet apart along fissures cemented, impregnated, and partly replaced by manganese oxide. The ore is accompanied by calcite, jasper, and hematite. In the shaft very little manganese oxide occurs below a depth of 20 feet. Hema- tite and calcite persist to the bottom of the shaft, however. In two or three of the open cuts, oxide appears to give way to hematite at a shallow depth, 1!JG MANGANESE IN CALIFORNIA [BuU. 152 as little as 5 feet below the surface. The fissures occur in rhj'olite and rhyolite breccia. The rock is brownish grray when fresh, but weathers reddisli. Shiny films of hematite appear alon*? many joints. The rhyolite contains a few small phenocrysts, in an aphanitic firoundmass. The rhyolite has a general northwest strike, and gentle dip to the southw^est. Several fissures occur on the property, of which at least three contain manganese oxide. The principal fissure may be traced for 2,300 feet. Manganese oxide occurs at intervals over onlj^ a small part of this dis- tance, however. This fissure has an average strike of N. G5° W., and a dip of 70° NE. Toward the north Avest end it is offset and splits into en echelon branches. At the extreme northwest end the fault is overturned and dips 70° SW. The dip passes through the vertical about 400 feet southeast of the shaft. The fissures are marked by smooth f ootwalls, which in many places stand up as scarps several feet high, all facing northeast. They possess smooth, polished surfaces, on which are seen narrow seams of calcite and jasper. The fissures are accompanied by brecciated zones commonly 1 foot to 10 feet wide. In places narrower zones of breccia extend at an angle into the wall rock. Some of the cemented brecciated zones appear to be more resistant than the surrounding wall rock and stand up in a manner resembling dikes. Manganese oxide occurs at various places along the fissure zones. Zones cemented by manganese oxide ordinarily have a width of 2 to 3 feet and a length of 30 to 100 feet. At one place northwest of the shaft, manganese oxide veinlets are scattered through a brecciated zone 20 feet thick. The manganese oxide is partly hard botryoidal psilomelane, and partly soft black oxide. In places concentric bands of hard oxide alternate with bands of a softer gray fibrous mineral. The impurities include vein- lets of later white calcite, hematite, a little chalcedony, and numerous rock fragments. The average grade of most of the ore zones is 25 or 30 percent manganese. It is thought that sorting of a product containing over 35 percent manganese would be very difficult. Assavs made bv the IT. S. Bureau of Mines are as follows : Percent Mn Fe SiO= 30.] 1.82 2S.7S 28.4 15.86 13.00 33.G 2.22 17.20 31.1 2.00 30.50 22. S 2.38 43.74 Lee Yim. Deposit. (By R. R. Morse, September 22, lf)18.) The main ore body in the Lee Yim deposit rests in sharp contact against hard red i-]iyolite agglomerate along the southwest. The pyroclastic nature of this "footAvall" is sometimes slightly obscured on the immediate fault face by a polished mirror of brick-red iron oxide. Commencing at the southern- most pit, where the contact of the ore body has been well exposed, this agglomerate footwall extends N. 80° E. for a distance of about 800 feet, weathering out prominently above the bench level. It then turns abruptly west and is easily traceable for an additional 700 feet, beyond which the region was not examined. Throughout this distance the hard footwall (lips 75° NE. The manganese oxide ore which rests against it, ranges in width between 2 and 15 feet. About midway along this zone, a second and parallel belt of oxide ore crops out about 200 feet southwest. Dense, dark-red platy rhyolite lies 1950] DESCRIPTION OF DEPOSITS 197 between. This ore likewise occurs witliin rhyolite aj^glornerate, the hard polished footwall of agg:lomerate dipping steeply northeast. The ore body is traceable at the surface for a distance of 400 feet, its outcrops ranging: in width from 1 foot to 4 feet. In this same locality and for 75 feet northeast of the main ore zone, a third and similar outcrop of ore occurs. This zone, however, is irregular and is not traceable at the surface. Farther northeastward from the ore- bearing agglomerate, and forming the top of the scarp, a red-weathering, greenish-gray rhj^olite flow crops out. The rhyolite agglomerate, because of its superior resistance to weathering, its peculiar texture and bright color, and its association with the ore bodies, is the most prominent member of the bedrock series. It consists of unsorted coarse and fine fragments of fine-grained brownish- gray porphyritic rhyolite embedded in a dense brick-red matrix made up of smaller fragments of rhyolite, quartz, and feldspar, through Mdiich a fine red dust of iron oxide is uniformly distributed. The fragments range in size from microscopic particles to 1.5 inches in diameter, sizes of 0.5 to 1 inch predominating. Boundaries of these fragments with the dense matrix are ever^^where clear cut ; their edges are sharply angular. These coarser fragments consist entirely of rhyolite in which small phenoerysts of orthoclase are sparsely distributed in a fine-grained crys- talline groundmass of alkali feldspars and quartz, glass being entirely lacking. The phenoerysts are 1 millimeter or less in diameter. Minute tabular feldspars with indices of refraction below 1.530 predominate in the groundmass in which also occur scattered grains of magnetite, and a minor amount of quartz. Scattered here and there, probably as original inclusions of the ferromagnesian minerals now partly or completely destroyed, occur small terminated prisms of apatite and an infrequent, highly birefringent needle perhaps representing zircon, but too minute for recognition. An irregular shred of pale-greenish ferromagnesian mineral showing characteristic cleavage angles of amphibole suggests a remnant of hornblende. Numerous dark, largely isotropic patches strongly suggest resorption of original ferromagnesian minerals. Many of these exhibit partial prismatic or tabular outlines and consist largely of fine magnetite, within which are remnants of highly birefringent cores, with the fine magnetite and considerable secondary red hematite dust trailing out in a manner suggesting flowage of the groundmass. These are believed to result from the magmatic resorption of primary hornblende, and perhaps in part biotite. In the groundmass, quartz is not recognizable in great abundance, the texture approaching ortho- phyric. The dense red matrix in which these rhyolite fragments are embedded owes its color to an abundance of fine red iron oxide dust. After removal of much of this hematite by leaching, the matrix is seen to consist of rock fragments and of finally comminuted dust of rhyolite, quartz, and orthoclase, all showing ragged edges. The smallest particles are so fine that they are scarcely resolvable by the microscope. The rock is thus seen to be pyroclastic, consisting of rhj'olitic tuff and fragments of lava of the same character, and may be termed rhyolite agglomerate. A second rock type is platj' red rhyolite, which crops out between the main ore zone and the adjacent zone to the southwest. Scattered equant 198 MANGANESE IN CALIFORNIA [BuU. 152 or slightly tabular phenocrysts of orthoelase and a few crystals of sodic plagioclase showing simple twinning, occur in a dense microcrystalline grounduiass carrying a large amount of red iron oxide. This rock evi- dently represents a thin rhyolite flow. A third type is greenish-gray rhyolite. The light colored rhyolite occurring northeast of the ore-bearing agglomerate exhibits scattered phenocrysts of orthoelase and oligoclase with the usual types of twinning in a light colored microcrystalline groundmass. Tender the microscope, flowage is indicated by the rough parallelism of the small laths of oligoclase and shorter tabular orthoelase, as well as by a tendency to orientation of the longer phenocrysts. In addition to the phenocrysts visible in the hand specimen are many phenocrysts showing micrographic intergrowths of quartz and orthoelase, as well as microperthitic inter- growths of the feldspars. The larger feldspar phenocrysts are frequently zoned. Embayed quartz boundaries and partly or completely destroyed hornblende prisms indicate magraatic resorption. Other areas of alter- ation products suggest resorbed biotite. These indications of original ferromagnesian minerals are of more frequent occurrence in this rock than in the two types of rhyolite above described. The manganese of the ore bodies of these claims is in the form of psilomelane with a minor amount of pyrolusite. Calcite, silica, chiefly in the chalcedonie form, and varying amounts of unaltered rhyolite frag- ments, constitute the gangue. A sample representing the average char- acter of the ore gave the following analysis : manganese, 32.6 percent ; ferric oxide, 1.2 percent ; total insolubles, 28 percent. The insolubles include a small amount of chalcedony and an abun- dance of small rhyolite fragments with which the ore minerals are closely intermixed. Calcite is present in numerous small veinlets cutting the ore minerals. Larger patches of calcite have grown about the other constitu- ents; so a single cleavage face frequently shows included areas of ore minerals and rhyolite fragments. It is probable that ore of higher man- ganese content than that of the above analysis could not be economically recovered by ordinary methods of hand sorting. Except for a narrow seam along the polished fault face of the agglomerate forming the "footwall" of the main ore zone, the ore is everywhere characterized by an agglomeratic texture ; sharply angular fragments of rhyolite occurring within and adjacent to masses of psi- lomelane, which in places serve as an apparent matrix and in other places appear as sharply angular fragments. Locally along the foot- wall, the ore is massive or faintly banded, or carries veins of coarser calcite up to half an inch in widtli. Irregularly shaped, barren or nearly barren "horses" of rhyolite agglomerate, and bunches of manganiferous calcite with a few bands or stringers rich in red iron oxide, occur in the ore. The agglomerate of the hanging wall is not so firmly indurated as that of the footwall. Distinction between low-grade ore and barren agglomerate of this transition is rather abrupt. A polished surface of the ore having the characteristic agglomeratic texture shows sharply bounded fragments of brown rhyolite embedded in and adjacent to areas of steel-blue psilomelane, also bounded by sharp and fre(juently angular borders, and a few patches of fibrous pyrolusite. Where these abrupt borders are lacking, the psilomelane serves as a matrix. Pyrolusite occurs as shining radiating fibers in numerous small 1950] DESCRIPTION OF DEPOSITS 199 spots, commonly giving the enclosing psilomelane an oolitic or spherulitic appearance. Dull brownish-black powder fills the interspaces between the fibers in a manner suggesting that the fibrous pyrolusite alters to the powder. In many of these spots nearly all the material is now powder, whereas in others, closely packed radiating or stellate fibers occupy most of the area. In many specimens, a central spherule of fibers and powder of the pyrolusite is surrounded by wavy banded rims of steel-blue psilomelane, or by alternating botryoidal psilomelane and very thin partings of the dull powder, passing outward into a broad area of massive psilomelane, which is sometimes bounded by an outer rim of calcite. These calcite halos are generally connected with one or more of the numerous minute veinlets of calcite which cut the ore at random. Within the inner wavy bands of psilomelane small bunches of pyrolusite fibers may be seen standing at right angles to the banding. On a polished surface of the ore the soft powder largely drops out, leaving the psilomelane with a notable pitted surface. In many specimens an angular area of massive bright psilomelane contains a small, more or less central kernel of unaltered rhyolite. Care- ful search fails to reveal embayment of edges or transitional borders of partly replaced rhyolite. On the contrary, the edges of the included fragments are everyM^here sharp. In specimens of ore close to the stringer along the footwall is an occasional small irregular patch of hard reddish- brown jasper. In the thin section no manganese minerals other than the oxides mentioned above are evident. It is evident that a passageway for the solutions depositing manga- nese minerals has been afforded along the fault cutting the rhyolite agglomerate. The massive ore of the stringer along this hard wall is evidentl}^ of vein origin. It would appear that the now softer rock of the hanging-wall side of this fracture was of sufficient permeability to favor a somewhat limited circulation, resulting in the deposition first of manganese minerals, and later of calcite, within the ashy matrix of the agglomerate. To what extent the extremely fine interspacial filling of rhyolitic ash may have been replaced by material from such solutions is not now determinable. It is certain that in many places in the ore, psilomelane is now the chief cementing material, but no definite evidence of the replacement of fragments was observed. Clues as to the nature of the original manganese mineral deposited are lacking. The oxides present no common features that might be interpreted as inherited structures. One possible exception may be noted, consisting of a small isolated cavity now partly filled with psilomelane, in which may be seen a faintly reticulated structure and parallel parting resembling what in certain other deposits of the state appears to be oxidation of bladed rhodonite to a siliceous oxide ore. The frequent sharp outlines of areas of massive psilomelane in this ore are partly, if not wholly, due to the intersection of calcite veinlets, more or less darkened by admixed manganese oxide powder. One somewhat different occurrence of psilomelane on the Lee Yim claims should be mentioned for the sake of completeness, though no com- mercial value is attached to it. This consists of shallow joint or fissure fillings, composed of small angular rock fragments and a few pieces of hard psilomelane embedded in a compact reddish or yellowish-brown 200 MANGANEWF. IX CALIF'ORNIA [Bull. 152 matrix of ealciiim (^•arhonate. This matrix dissolves readily in cold liydro- ehlorie acid leavin«>: suspended a fjreat quantity of fine particles of red liematite and an unattached residue of frajrments of psilomelane and rhyolite, a few small shreds of bleached mica, and many travel-worn {>rains of quartz evidently of detrital oriorin. The veinlets often have thin outer selvedges and inner bands of massive psilomelane, 1 inch to 2 inches in thickness. The fillings as a whole are seldom over 6 inches thick. They are vertical, or nearly so, and may be traced 50 to 75 feet, cuttinj;- the ore zones nearly at riirht aufrles. The ore of these de])osits is of a unifoi-mly low jrrade. The past ship- ment of carefully sorted ore averao:ed only 38 percent mangranese. It is doubtful that a product of better than 30 percent manfranese can be l)rofitably recovered by ordinary methods, (iwing to the nature of the impurities the ore would seem better adapted to some form of mechanical concentration, rather than sortinji: to hi inches thick, mostly dipping northeast. One vein (5 indies thick is about half calcite and half psilomelane. I'silomelane bands are on outside, calcite in center 22 7. Breeciated zone 10 feet thick, more or less penetrated with psilome- lane and calcite veinlets. and containing numerous large rock frag- ments. Some thick veins of coarsely crystalline calcite. Also veins of neaidy pure psilomelane 8 to 4 inches thick — in places G to 8 inches thick 10 Total H~> 202 MANGANESE IN CALIFORNIA [BuU. 152 No. 12. Monument King Deposit (Manganese King, Hidden Treas- ure, Cross Roads). (By Ivan F. Wilson, March 17, 1943.) A deposit known as the Monument King, Manganese King, or Hidden Treasure is 2.5 miles west of Monument Peak in the Whipple Mountains, 8 miles west of Cross Koads. Cross Roads is 8 miles north of Parker, Arizona, the site of a Metals Reserve depot. From Cross Roads a road is taken north- west toward Copper Basin. At 4.6 miles from Cross Roads a right turn is made, and the manganese camp is at a total distance of 7.9 miles by road from Cross Roads and 15.7 miles from Parker, Arizona. The main part of the deposit is about 1 mile from the end of the road. This distance is covered by a tractor trail which is too narrow and steep to be used by trucks. Ore has been hauled over this trail by a trailer towed by a tractor. Workings are scattered at intervals along the steep southwest slope of a northwest trending ridge near the head of Whipple Wash. The deposit is in sec. 1, T. 2 N., R. 25 E., and sec. 6, T. 2 N., R. 26 E. It is joined on the southeast by the Moulton deposit (San Bernardino 25). The power of attorney for the property is held by Fred M. Hall of Los Angeles. This property was formerly leased to Moulton and Clark but is now leased to Bowen and Cady. Five or six men have been working on the property. The deposit was mined during World War I, and was described in reports at that time by Jones ^ as the Hidden Treasure group and as the Hidden Cross properties. This deposit and the Moulton deposit (San Bernardino 13) to the southeast, have been referred to as the Cross Roads deposit. The production from these two mines together was 160 tons in 1917 and 1918, containing 46 percent manganese, 3 percent iron, and 3 percent silica. It is not known what proportion of this came from each mine. In 1943 the property shipped 12 tons containing 39.01 percent manganese to the Metals Reserve depot at Parker, Arizona. Mr. Moulton states that 1,800 tons was shipped from the Monument King (San Ber- nardino 12) and the Moulton properties during the last w^ar, but this figure seems large in view of the size of the workings. Development consists of about a dozen open cuts scattered over a length of 3,000 feet. The largest of these is 30 feet long, 12 feet wide, and 15 feet deep, from which ore has been stoped. The deposit consists of manganese oxide and hematite occurring in lenticular bodies associated with jasper in limestone. The limestone is enclosed in a thick series of sediments, mainly brown sandstone and volcanic breccia. The manga- nese oxide in general lies parallel to the bedding of the limestone ; how- ever, in places it seems to cut across the bedding. It is nearly everywhere accompanied by jasper. The manganese oxide is often underlain by jasper ; in places it seems to wedge into it along the strike. The manganese oxide consists mainly of hard blue-black material of the psilomelane type, along with soft black oxide, accompanied by a small amount of calcite and by considerable hematite. The psilomelane is not so markedly botryoidal as in the typical fissure deposits of the desert region. Nearly all of the pieces of manganese oxide are coated with hematite. In some of the deposits fairly large bodies of hematite occur with the manganese oxide, or in place of it. Apparently the manganese oxide may be separated readily from the bulk of the hematite, inasmuch as the ore shipped in World War I carried only 3 percent of iron. The 1 Jones, E. L. Jr., Deposits of manganese ore in southeastern California: U. S. Geol. Survey Bull. < 10 E, pp. 185-208, 1919. 1950] DESCRIPTION OF DEPOSITS 203 ore is massive, and much of it is high grade, containing probably 45 percent manganese. No. 13. Moulton (Red Cross) Mine. (By Ivan F. Wilson, March 17, 1943.) The Moulton mine, known during the last war as the Red Cross, adjoins the Monument King property (San Bernardino 12) on the southeast in the Cross Roads district, in sees. 6 and 7, T. 2 N., R. 26 E. It is reached by proceeding northwest from Cross Roads tOAvard Copper Basin and turning right 4.6 miles from Cross Roads. The manganese camp at the end of the road is 7.9 miles from Cross Roads and 15.7 miles from Parker, Arizona. The workings are then 0.1 to 0.2 mile to the north up a steep ridge. A cable tramway down the slope of this ridge was being constructed when the mine was visited. The property is owned by C. E. Moulton and leased to Wm. Bradbury of Parker, Arizona. Five men have been working on the property since January 25, 1943. The deposit was mined during World War I, along with the Monu- ment King deposit (San Bernardino 12). The production from the two mines together has been listed as 160 tons in 1917 and 1918, containing 46 percent manganese, 5 percent iron, and 3 percent silica. It is not known what proportion of this came from each of the two mines. No ore has been produced from the Moulton property during the present war, but the operators were preparing to ship at the time the property was visited. Development consists of 5 open cuts and 2 small caved tunnels. The general geology is the same as at the Monument King deposit and the report on that property is referred to for the details. The deposit consists of lenticular bodies of manganese oxide and hematite associated with jasper in limestone, which in turn is enclosed in brown sandstone and volcanic breccia. The manganese oxide may have resulted from replacement of the limestone, or it may represent an original bedded deposit. Very little ore is now seen in the old workings, which date to World War I. A new open cut was being developed at the time of the writer's visit, and this revealed a bed of solid ore 2.5 to 3 feet thick, exposed for the length of the cut and for an additional 40 or 50 feet. Between 10 and 15 tons of ore has been mined. This ore probably runs over 45 percent manganese. The ore is mostly of the hard psilomelane type, with some calcite and coatings of hematite. The ore body strikes N. 35° W., and dips 70° to 80° SW. About 1,000 feet north of the open cut mentioned above is an expo- sure of ore which has been undeveloped, but which the operators are planning to explore in the future. Ore having a thickness of 1 foot to 2 feet is exposed at intervals over a distance of 150 feet. The ore is associ- ated with jasper in limestone, and appears to be a long lenslike body paralleling the bedding of the limestone, although in places it appears to cut across the bedding. The general strike is N. 40° W., and the dip is 40° SW. The ore zone contains alternating concentric bands of material of the hard psilomelane type and soft black oxide. The ore is coated with hematite and contains a small amount of calcite. No. 14. New Deal Mine (Owl Hole, Owl Head). (By F. S. Hud- son, September 25, 1918.) The New Deal, Owl Hole, or Owl Plead mine is 1.5 miles northwest of Owl Hole Springs on the southeast flank of the Owl Mountains. It probably is in sec. 18, T. 18 N., R. 3 E., in northeastern San Bernardino County. It is owned jointly by Alex Yoeman, 0. H. Stevens, and E. P. Bryan, of Los Angeles. At the time of the writer 's visit, 204 MANGANESE IX CALIFORNIA [BuU. 152 the best road for reaching: this locality by automobile was from Randsburg via (Jranite Well, a distance of 70 miles. Xo jrreat difticulty with soft sand was experienced on this route. An attempt was made to take a shortcut road from Trona to the above mentioned road, northeast of Granite Well. At a point 8 miles east of Spanjrler Sidin«>-, on the American Trona Company's railway, heavy sand was enconntered that prevented crossinji" a low ranfi:e of hills. The road from Owl Sprinj; to Silver Lake via Saratoira Sprinjj;, was said to be very difHcnlt. For this reason an attempt was made to reach Silver Lake by the road around the south side of Leach Lake. Heavy sand barred pro<>ress up a canyon in the mountains southeast of Leach Lake. The ore from the mine was hauled bj" tractor and trailers to Riggs on the Tonopah & Tidewater Railroad, a distance of 45 miles. The Owl Mountains consist of a core of ci-ystalline rocks including granite and marble, flanked on the south and southeast by sediments of probable Tertiary age. The basal member of these sediments is a thick mass of moderately well consolidated conglomerate, showing no sign of bedding, made up of angular to subangular boulders, predominantly of granite, less commonly of marble, in a matrix of sand and clay. The boulders range in size from a fraction of an inch to several feet in diameter. The formation is without much doubt a middle or early Ter- tiary fanglomerate. Above this fanglomerate, which is perhaps 1,000 feet thick, are well-bedded, gray and pink sediments, having the appear- ance of lake deposits. The manganese occurs in veins cutting the con- ■ glomerate. The materials of these veins are hematite, black manganese oxides, and boulders derived from the conglomerate walls. No definite walls were seen, the mineralization fading gradually into the con- glomerate. Two sets of workings called the east workings and the main work- ings are present. In the east workings an ore zone with a maximum width of 30 feet has been proved for over 50 feet vertically and for 100 feet along the northwest strike, by a shaft and open cuts. The ore zone consists of boulders of granite in a matrix of bright red hematite material and black manganese oxides. The northeast Avail of the ore zone is coarse granite, the southwest wall is iiulefinite, as the mineralized zone grades into barren conglomerate. About 50 feet northeast of the workings is an exposure of granite in intrusive contact with marble. Both rocks are cut by numerous veins 0.5 inch to 1.5 inches wide, but in one place 2.5 feet wide. These veins are composed of psilomelane and ealcite : the latter mineral is in the center of the vein and represents a later period of mineralization than the psilomelane. The northeast part of the ore zone contains the most manganese. It is thought that the mineralizing solutions entered along a fissure that was developed at the contact of the conglomerate with the older rocks, then passed out through smaller fissures into the granite and marble on the one side, and into conglomerate on the other side. Most of the material in solution seemingly was deposited before traveling any great distance. The ore here cannot be hand sorted to advantage as it contains, in addition to the boulders, a considerable amount of gi'it and nnich hema- tite. A large sample was taken for test ))urposes. Assay of this gave 17.5 percent manganese, 35.9 percent insoluble, and 11.3 percent ferric oxide. 1950] DESCRIPTION OF DEPOSITS 205 The main workings are 0.3 mile west of the east workings. Two approximately parallel veins have been uncovered. The northern and principal one, strikes N. 30°-45° W. The southern vein is 75 yards to the southwest and strikes N. 50° W. The northern ore zone has been developed to a vertical depth of 90 feet by an incline which follows the dip of 65° to 70° SW. At 20 feet depth the vein has been followed for 150 feet by a drift which communicates with the surface. This is the haulage level. At the 65-foot level is a 40-foot drift trending S. 45° E., and a 60-foot drift trending N. 32° W., from the incline. Short drifts have been made to the northwest and southeast at the bottom of the incline. The ore zone consists of masses of black oxide ore, and of irregular veins 1 foot to 4 feet in width in the conglomerate. In the drift at the bottom of the incline is a maximum width of 10 inches of good ore. Nothing was seen here that could be worked profitably. A sample taken across 4 feet of low-grade ore at the end of the northwest drift assayed 16.4 percent manganese, and 60.7 percent insoluble. The ore above the 65-foot level has been stoped to the 20-foot level for 25 feet to the southeast, and for 40 feet northwest of the incline. The ore body was followed to its end on the southeast, but only 1 foot to 2.5 feet of ore is exposed in the 65-foot level for 20 feet beyond the stoped part. A sample taken across 2 feet of ore at the northwest end of the drift assayed 17.3 percent manganese, and 51.3 percent insoluble. On the 20-foot level northwest of the incline, 2 feet of good ore extends for one-half the dis- tance to the end of the drift. Along the rest of this distance the good ore is from 0.5 foot to 1.5 feet wide. A sample taken across 3 feet of good ore at a point 50 feet northwest of incline assayed 31.4 percent manganese, and 32.7 percent insoluble. The above described workings have furnished most of the ore that has been shipped from this property. The total amount shipped, according to the Tonopah & Tidewater Railroad agent at Ludlow, is 480 tons. The southern ore zone has been followed for 75 feet along the strike, to a maximum depth of 15 feet below the surface of the ground. Sixty tons of ore, apparently of shipping grade, has been mined and stacked here. From the size of the workings, about 200 tons of ore and waste were removed to obtain the 60 tons of ore. No. 15. Norihrup Prospect. (By R. R. Morse, September 1918.) The Northrup prospect is in sec. 8, T. 8 N., R. 3 E. The claim is said to have been located by a Mr. Northrup. The ore in this claim is reported to be similar in appearance to that of the Black Raven prospect (San Ber- nardino 6). As the size of the outcrop was described as being "about 6 feet by 10 feet" it was not considered worthy of investigation. No. 16. Orchard (Dunhar) Deposits. (By Parker D. Trask, August 12, 1942.) The Orchard deposits are about 1 mile west of Lake Havasu, due west of the Thompson deposits which are across the lake in Arizona, 14 miles above the Parker Dam. They are located in sec. 10, T. 3 N., R. 26 E. The owners are Robert Orchard of Glendale, and Charles Dunbar of Parker Dam. An adit 50 feet in length has been driven into the ore body to ascertain its nature at distance from the outcrop. The beds strike north and dip 30° W. They consist of massive fanglomerate more than 100 feet in thickness. Some 40 or 50 feet of this zone is stained black M'ith manganese oxide, which forms fillings around the rock constituents. The fanglomerate is exposed for 1,000 feet along the strike and forms a 206 MANGANESE IN CALIFORNIA [BuU. 152 massive reef. It is offset 50 feet in the middle by a cross fault. The grade of the ore is different on the two sides of the fault. North of the fault it is mostly 5 percent or less, and south of the fault it is chiefly 6 to 8 percent, but in some places it is 10 or 12 percent. The ore seems to be related to strike fissures that cut the fanglomer- ate, for the grade is materially different on the two sides of some fissures. However, it is essentially the same on the two sides of others. The ore at first appearance seems to be a bedded deposit, but the difference in degree of mineralization on the two sides of fissures suggests strongly that the ore in part at least is of fissure origin. No. 17. Owh Spring Prospect. (By C. B. Hunt and Edgar Bowles, 1942.) The Owls Spring deposit is in sec. 18, T. 18 N., R. 3 E., in the Owlshead Mountains, 2 miles west of the Emma deposit (San Ber- nardino 9). The ownership Avas not ascertained. The ore body consists of manganese oxide disseminated in bedded deposits, presumably of lacus- trine origin. The deposit is 1,000 feet in length and the dip is 40° to 50°. The average grade is less than 10 percent manganese. No. 18. Beinerth Prospect. (By R. R. Morse, September 23, 1918.) The Reinerth prospect is in the Ludlow district in sec. 5, T. 8 N., R. 8 E. It is located near Milepost 7, on the Tonopah and Tidewater Railroad, 7 miles north of Ludlow, and a few miles northeast of the Lee Yim claims (San Bernardino 10), on the east slope of the Cady Range. The claim is owned by E. A. Reinerth, an official of the railroad company, living in Ludlow. All the ore in this locality is said to have been removed, furnishing a shipment of 10 tons, sold to the Noble Electric Company, and shipped from Ludlow to Heroult in the latter part of December 1917. The claim was not examined. The ore is similar in character to that of the Lee Yim deposits. The 10-ton shipment was the result of very painstaking hand sorting. The assay returns from the smelter showed a manganese content of 34.7 percent. The owner states that no additional ore is on the claim. No. 19. Stewart Mine. (By Ivan F. Wilson, March 8, 1943.) The Stewart mine is on the north flank of the Whipple Mountains in the NW^ sec. 6, T. 3 N., R. 25 E. The nearest rail point is Needles, 41 miles north by road. The ore is hauled to the Metals Reserve depot at Parker, Arizona, a distance of 64.5 miles by road. The mine is reached from the road between Needles and Rose (U. S. Plighway 95). A private power- line road turns off to the southeast at a point 27 miles north of Rose and 21 miles south of Needles. This powerline road is followed for 9.4 miles, where another road turns off to the south. This road is followed for an additional 10.8 miles to the mine. The mine is owned by J. W. Stewart, and is leased to the Mineral Materials Company of Alhambra. Five men were working on the property when visited. In 1942 one carload of 17 tons, containing 35.95 percent manganese, was sent to the Metals Reserve stock pile at Phoenix, Arizona. Two addi- tional carloads fell below 35 percent and were rejected, and it is under- stood that these were reshipped to the Kaiser plant at Fontana. In 1943, until March 18, 109 tons had been sent to the Metals Reserve depot at Parker, Arizona. The individual shipments ran between 35.84 and 39.66 percent manganese. A composite sample showed the other constituents to be aluminum, 2.61 percent; iron, 2.58 percent; silica, 5.37 percent; zinc, nil ; phosphorus, 0.02 percent. 1950] DESCRIPTION OF DEPOSITS 207 The main ore zone has been developed along three levels, within a small vertical interval. At the surface is an open cut 52 feet long and 15 feet deep; 20 feet below the surface is a tunnel 42 feet long, with a cut 41 feet long at the mouth ; at the mouth of the tunnel is a winze 32 feet deep from which another tunnel has been driven for 33 feet. The two tunnels are driven in the direction S. 15° E. Other open cuts and trenches are in the vicinity, and to the east is a crosscut tunnel 25 feet long with a 30-foot cut at the mouth. The above mentioned workings are on the south side of a steep canyon. The level of the main tunnel is 20 feet above the bottom of the canj'on. This locality will be referred to as working place No. 1. Across the canyon and about 1,000 feet farther west at working place No. 2 is another tunnel 20 feet long, with a cut 25 feet long at the mouth, driven N. 65° W. into the slope. About half a mile farther west, near the top of a low ridge on the north side of the canyon, are some other workings, called workings No. 3, including a shaft 18 feet deep and a tunnel 45 feet long trending N. 40° W. from the bottom of the shaft. The deposits consist of fissure zones in fanglomerate impregnated with manganese oxide. The main fissure at working place No. 1 has a smooth footwall and a gradational hanging wall. It strikes N. 10°-15° W. and dips 65° to 70° W. The wall rock is a poorly sorted, well indurated sedimentary breccia, containing angular to subangular fragments 1 inch to 6 inches in diameter in a red to orange, sandy, and clayey matrix. The fragments are chiefly of granitic and metamorphic rocks, sandstone, and a few volcanic rocks. The fanglomerate strikes N. 80° W., and dips 10° S. Zones of varying width adjacent to the fissures are cemented, impregnated, and partly replaced by manganese oxide. The manganese oxide is mainly a soft, black crystalline mineral — probably pyrolusite. Some hard botryoidal material of the psilomelane type is also present, but the soft oxide is more prevalent than in most of the fissure deposits of southeastern California. Brown calcite, probably manganiferous, occurs in many places and it seems likely that this may be the primary ore. In the crosscut tunnel at working place No. 1 a vein of nearly solid brown carbonate, 2.5 feet wide, occurs. It is cut by veinlets of white calcite which appear to be later in origin. The brown calcite is within 5 to 10 feet of the surface in places. Hematite and limonite also accom- pany the manganese oxide, and appear to increase in proportion with depth below the surface. The general run of the ore is low grade, probably between 15 and 25 percent manganese. The impurities are wall rock, calcite, hematite, and limonite. It has been extremely difficult to sort out a product con- taining as much as 35 percent manganese. In the process a large amount of low-grade ore has been mined and rejected on the dumps. This mate- rial probably could be sold to the Kaiser plant at Fontana, but the operators were doubtful whether the price received would paj- for the cost of transportation and loading at the mine. No. 20. Turner Prospect. (From files of U. S. Geological Survey, 1918.) A deposit said to be owned by M. C. Turner is located a few miles south of Newberry, in T. 8 N., R. 3 E., presumably in sec. 9. No other information is available. 208 MANOANESK IX CAMFORNIA [BuU. 152 No. 21. Virion Proapcct. (From files of U. S. Geological Survey, 1918.) A deposit said to be owned by Al Vivian is in T. 3 N., R. 5 E., some 10 miles northeast of Palm Sprinjrs. No other information is available. SAN DIEGO COUNTY No. 1. Clark Pro>ipccL (P,v F. S. Hudson, May 16, 3918.) W. S. Clark of Fallbrook, owns two claims in T. 9 S., R. 2 W. In the SEiNW^ sec. 18, at an altitude of 1,620 feet, a ]>it exposes pranite imprep:nated with black oxide of manganese. The prospect of finding ore of commercial grade is extremely poor. An open cut in the SE jSW^ sec. 7, exposes an aplite dike within Avhieh manganese occurs as dark brown stains. The ore is of low grade. Local report credits one of the Clark claims with ore carrying 18 percent manganese. Nothing was seen at eithf^r claim that would carry over 5 percent manganese. No. 2. Bel Monte Prospect. (By Hpangler Rickcr, March 1941.) A deposit said to be owned by M. J. Flynn of San Ysidro is located 4 miles northeast of Jacumba in T. 17 S., R. 8 E. The ore body consists of manganese oxides in a shear zone in granite. The ore is exposed for a distance of 20 feet and has an average width of 2 feet. A representative sample assayed 14.5 percent manganese. 3.3 percent iron, and 65.6 percent silica. The property has not been developed. No. 3. Engineer's Springs. (By F. S. Hudson, .lune 13, 1918.) According to the State Division of Mines report on San Diego County,^ a lens of banded red and Mdiite jasper occurs in black shale in sec. 22, T. 18 S., R. 2 E., south, of Dulzura. Quartzite and granite are also said to occur there. As Franciscan rocks have not yet been reported from this area, and as any chert locality is a possible source of manganese, the writer spent several hours in examination of this section. No jasper, black shale, or quartzite was found. The predominating rock is rhyolite, which under the hand lens is seen to consist of small blebs of quartz and crystals of plagioclase in a fine-grained felsitic matrix. Much of the rhyolite is "sheeted" and resembles, in the outcrop, either quartzite or chert. At several prospect pits in the rhyolite, the rock is bleached white, sericitized, and often stained red with iron oxide. This red stain fre- quently occurs in concentric bands. Dr. C. C. Valle of San Diego, w'ho owns this proi)erty, showed the writer several polished sections of jaspillite or jaspcroid alteration of rhyolite. These are siliceous, and the high ]>()lish exhibits the iron stained bands to good advantage. The prospect of finding manganese in bedded deposits of the Coast Range type in the country south of Dulzura is evidently quite poor. As far as could be ascertained, no manganese of any type has been found here. No. 4. Jacumha Group. (Modified slightly from original descrip- tion in California Min. Bur. Rept. 20, p. 374, 1924; and in California Div. Mines Rept. 35, p. 30, 1939.) The Jacumba group of claims is 1 mile northwest of Jacumba in sees. 5 and 6, T. 18 S., R. 8 E., at an altitude of 2,900 feet. p]ight claims have been located by B. F. Stanwood and J. J. Curl of San Diego. A number of silicified outcrops, with general north- west strike, occur in the granite. At several places these outcrops are > Trask, Parker D., Wilson, Ivan F., and Simons, Frank S., Manganese deposits of California: California Div. Mines Bull. 125, pp. 85, 165, 1943. 1950] DESCRIPTION OP DEPOSITS 209 heavily stained witli manganese oxides. Analysis of ore extracted from different prospeet holes is reported as manganese, 7 to 22 percent ; iron, 14 percent; silica, 16 to 25 percent. Only assessment work has been done on the claims. Another gronp of claims is located 1 mile noi'thwest of Jacumba, in sees. 5 and 6, T. 18 S., K. 8 E. They are owned by Dr. M. C. Harding of San Diego. Occurring on this property is a 4-foot vein of a low-grade manganiferous iron, with a high silica content. Two shallow test pits have been put down, revealing the ore in place. No. 5. Machado Prospect. (By F. S. Hudson, May 16, 1918.) The Machado prospect is 5 miles south of Temecula in the SW^NW^ sec. 6, T. 9 8., K. 2 W. It formerly was owned by George Daly, but it is now the property of M. Machado of Temecula. The ore body consists of a manganese-stained zone in a mass of pegmatite and aplite, which strikes N. 70° W., along the course of the hill. No definite veining was seen, and not over 50 pounds of ore was visible. The prospect is not promising. No. 6. Eanirod Prospect. (From files of V. S. Geological Survey, 1941.) A deposit owned by V. W. Deaver is situated near Jacumba in T. 18 S., K. 8 E. It is said" to be of little value. No. 7. Buhij Prospect. (By F. S. Hudson, June 12, 1918.) A pros- peet for manganese, the property of D. A. Ruby of Boulevard, San Diego County, is 2 miles southeast of a point on the San Diego-Imperial Valley Highway, 3 miles .southeast of Boulevard. It is said to be in sec. 16, T. 18 S., R. 8 E. The ore-bearing material is a bed of siliceous manganese ore enclosed in quartz-mica schist. The strike is N. 60° W., the dip is north at a high angle. The schist occurs as a body less than 50 feet thick, in granite. The ore bed is 7.5 feet thick. The lower 5 feet is gray quartzite with bands of pink and brown, siliceous manganese ore. Some of the fine- grained gray quartzite is clearly derived from chert, and for this reason all the quartzitic material is thought to represent a metamorphosed chert. North of this more siliceous portion is 1.5 feet of nearly pure, pink manga- nese silicate, beyond which is 1 foot of oxidized ore of good grade. Manganese garnet crystals up to half an inch in size occur at about the middle of the quartzose bed. Garnet crystals of microscopic size together with a few rhodonite crystals were identified in a thin section of the fine-grained, gray metachert. A winze has been sunk along the oxidized part of the ore body. This body decreases in thickness rapidly with depth. A narrow pegmatite stringer, which is seen in the hanging-wall schist at the top of the winze, increases in width with depth and appears to ' ' cut out ' ' a portion of the ore body. The deposit is thought to be due to the contact-metamorphic action of pegmatite and granite on a bed of siliceous manganese carbonate or carbonate-oxide ore. No. 8. Sunrise Mhie. (Modified slightly from original descrip- tion in California Div. Mines Kept. 35, p. 30, 1939.) The Sunrise ]\Iine is OA^^led by Calvin W. Garrison of San Diego, and is located in sec. 10, T. 13 S., R. 5 E., about 9 miles east and north of Banner. A 5-foot vein of manganese oxide occurs on this property, carrying gold. The property has been developed by 2 tunnels, one 8 feet in length, and the other 50 feet. It is now idle. 210 MANGANESE IN CALIFORNIA [Bull. 152 1950] DESCRIPTION OF DEPOSITS 211 No. 9. Turner Prospect. (By F. S. Hudson, June 11, 1918.) The Turner prospect is on a claim owned by J. C. Turner of San Diego. It is in the SE^NE^ sec. 31, T. 14 S., R. 5 E., on a gulch which drains to Deer Park about 0.8 mile to the southwest. The ore bed is a banded siliceous rock of blue-gray color. The fine-grained parts indicate their derivation from chert, but the greater part of the material is a medium-grained, iron-stained quartzite. Veinlike masses of white quartz cut the quartzite. Numerous fractures in the quartzite are coated with manganese oxide ; a few fairly large pieces on the dump may carry as mucli as 5 percent manganese. This quartzite occurs as a lens 5 feet thick inclosed in "gnarly" quartz-mica schist. About 300 yards to the southwest, light- colored gneiss was seen, probably intrusive into the schist. In the NE:^SWi sec. 31, a basic or intermediate plutonic rock is exposed. Nothing was seen here that would encourage further prospecting for manganese. SAN JOAQUIN COUNTY Geology of the Ladd- Buckeye Area ^ General Features. An area 12 miles long and 2 to 4 miles wide in the southwest part of San Joaquin County and the northwest part of Stanislaus County between the Ladd mine on the north and the Buckeye mine on the south, has produced more manganese than any other dis- trict of like dimensions in California. The location is shown in figure 5. Prior to World War II this area produced 50,000 tons of manganese ore, approximately 50 percent of the total production in the state up to that time. During World War II it yielded more than 13,000 tons, or more than 25 percent of the production from the state during that period. The ore has come principally from five deposits. The Ladd mine (San Joaquin 5) has produced approximately 30,000 tons, all prior to the termination of World War I. The Buckeye mine (Stanislaus 4) yielded 15,000 tons before World War II, and more than 11,000 tons during World War II. The Cummings (San Joaquin 3) and Liberty (Stanislaus 16) mines each produced more than 2,000 tons, mostly prior to World War II; and the Mahoney mine (San Joaquin 6) more than 1,500 tons during World War II. The U. S. Geological Survey began a detailed study of this district in 1940, when the imminence of war stimulated search for domestic sup- plies of manganese. The region was particularly favorable for investi- gation because it is one of the few places in California where the struc- ture of the Franciscan group, the principal host of manganese in the Coast Ranges, is relatively simple. In the study of this area, special attention was given to the mode of origin of the manganese deposits, in order to develop geologic criteria which would facilitate the prospecting and development of manganese deposits in the Franciscan. The field work was carried on by D. C. Cox, S. C. Creasey, F. Hoyt, S. G. Lasky, John Nelson, H. P. Norbeck, W. G. Pierce, F. S. Simons, A. F. Shride, P. D. Trask, F. D. Trauger, C. R. Warren, and I. F. Wilson. Lasky was in charge of the field party from July 1940 to May 1941, and Trask the remainder of the time. 1 By Parker D. Trask and W. G. Pierce. 212 MANGANESE IN CALIFORNIA [Bull. 152 The aroal geolop:y was mapped on airplane photographs made by the Agricultural Adjustment Administration. The photographs were enlarged two diameters to a scale of approximately 1 to 10,000. The geology was compiled on a scale of 1 to 12,000 on a topographic base map made from airplane jihotographs by means of a stereo-compara- grapli. supplemented by appropriate field triangulation (pi. 4). The topographic base map was made by W. G. Pierce, A. F. Shride, and P. D. Trauger. The U. S. Bureau of Mines explored the de])osits at the Ladd and Buckeye mines between August 1940 and June 1})41. M. E. Volin was in charge of this work. The Bureau opened up the adits, drove several crosscuts, sampled extensively, and sank 15 drill holes — five at the Ladd mine, six at the Fabian mine 2,000 feet north of the Ladd mine, and four at the Buckeye mine. The estimates of grade and reserves of the Ladd mine are based on assay data supplied by the Bureau of Mines. The area is in rugged country, ranging in altitude from 600 to 3,000 feet. The four main streams. Corral Hollow, Lone Tree, Hospital, and Ingram Creeks, carry water throughout most of the year but the tributaries are dry during the latter part of the summer. The five principal mines are accessible by roads. The distances to the nearest railroad from these mines are as follows: T^add mine, 7 miles to the Western Pacific Railroad at the gravel pits at the mouth of Corral Hollow, and 13 miles to the Southern Pacific Railroad at Tracy ; Mahoney mine, 8 and 12 miles, respectively, to these points; Cummings mine, 13 and 17 miles, respectively to these same points ; and Buckeye and Liberty mines, 16 miles to the Southern Pacific Railroad at Vernalis. An account of the general geology of the region is given by Ander- son and Pack.- A detailed description of the geology of the Tesla quad- rangle which adjoins the Carbona quadrangle on the west, is given by Hue3^■'* General discussions of the sandstone and chert of the Franciscan, have been written by Davis.^ The manganese deposits are in the Franciscan group of Jurassic ( ?) age, and the geologic mapping was confined almost entirely to this forma- tion (pi. 4). The Franciscan rocks are bounded on the northeast by the Tesla and Lone Tree faults, which bring the formation into contact with the San Pablo (Miocene) formation in the north part of the area, and with the Panoche (Upper Cretaceous) and ITorsetown (Lower Cre- taceous) elsewhere. Recent and Pleistocene landslides are found through- out the area ; and in places of gentle slope a mantle of alluvium commonly blankets the land to depths of 1 foot to 20 feet. Franciscan Oroup. The Franciscan in the Ladd-Buckeye area includes a wide variety of rocks : sandstone, chert, shale, conglomerate, limestone, greenstone (altered basalt and andesite), diabase, granophyre, diorite, gabbro, serpent inized peridotiti". phyllite, marble, glaucophane schist, and related schists. The thickness of the formation in the area mapped is more than 10,000 feet. The base of the formation is not exposed. 2 Ander.son, Robert, and Pack, R. W., Geolopry and oil resources of the west border of the San Joaquin Valley north of Coalinga, California: U. S. Geol. Survey Bull. 603, 1915. " lluey A., Geology of the Tesla quadrangle, California : California Div. Mines Bull. 140, 75 pp., 1948. < Davis, E. F., The Franci.scan sand.stone : Univ. California, Dept. Geol. Sci. Bull. 11, pp 1-44, 1918 . . . The radiolarian chert of the Franciscan group: Univ. California, Dept. Geol. Sci. Bull. 11, pp. 235-432, 1918. 1950] DESCRIPTION OF DEPOSITS 21:] The Franeiseaii group consists predominantly of sandstone and shale. Conglomerate occurs in only a few lenses less than 25 feet thick. Limestone is also present in a few places. The sandstone is found mainly in massive beds separated by thin shale beds. It is feldspathie and con- tains numerous fragments of hardened mud or shale flakes up to an inch in diameter. In contrast with the sandstone of younger formations, particularly with the Cretaceous sandstone which it superficially resem- bles, the sandstone of the Franciscan is relatively rich in fragments of dark (ferromagnesian) minerals and relatively poor in mica. The shale is mostly in thin beds less than 6 inches thick, but in places is 50 to 100 feet thick. "West of the Ladd mine the shale is locally altered into phyllite. The color of the shale is gray, red, or chocolate brown. In places the shale grades laterally into chert. The chert is found in lenses which range in size from small nodules an inch in length and 0.2 inch in thickness to bodies more than 1.000 feet in thickness and 3 miles long. The lenses commonly vary greatly in thick- ness within short distances. Rates of increase in thickness of 1 foot for each foot of length, have been observed. The chert is of two types : (1) red or chocolate-brown chert, in beds 1 inch to 6 inches tliick separated by shale beds of similar color, 0.05 inch to 2 inches thick ; and (2) white, light-gray, or pale-green chert either in alternating layers with shale, similar to the first type, or in massive beds. Most of the massive beds are 5 to 10 feet thick, but some beds are 40 feet thick. In many places the chert contains small pale round objects which are the remains of radiolaria. These radiolaria seemingly are of marine origin.^ Detailed mapping of the individual chert beds (pi. 4) shows that they are interbedded in sandstone and shale. Some of the chert bodies are lenses in the elastic rocks ; others grade iuiperceptibly into sandstone or shale along the strike ; and still others interfinger or feather out in the sandstone or shale. In one place in Sulphur Gulch on the east side of Hospital Canyon, the chert grades into sandstone through an intermedi- ate zone in which the chert contained a multitude of loosely disseminated sand grains. In this intermediate zone, the grains seem to have been sus- pended in a jellylike mass, which subsequently consolidated. The chert beds and lenses are found in two main zones, one near the Ladd mine and the other near the Buckeye mine. These zones seem to be at essentially the same stratigraphic position. Near the Ladd mine, chert is found through a zone 4,000 feet in thickness ; and at the Buckeye mine, through a zone nearly 10.000 feet in thickness. Between these two mines the indii-idual chert bodies are notably thinner, and the zone in which they occur likewise is materially thinner than at the mines them- selves. For a distance of 3 niiles between Hospital and Lone Tree Creeks the chert is restricted to a zone less than 1,000 feet thick, and only a few thin chert beds are present. The change in thickness of the chert layers and of the stratigraphic zone in which they are found is conspicuous west of the Buckeye mine. Within a distance of slightly more than 2 miles this zone changes from 10,000 to 1,000 feet in thickness. The individual chert beds converge to the west like ribs of a fan. Their mappable con- tinuity rules out the possibility that the decrease is the result of faulting. s Davis, E. F., The radiolarian chert of the Franciscan group: Univ. CaUfornia, Dept Geol. Sci. Bull. 11, pp. 353-401, 1918. 21-1 MANGANESE IN CALIFORNIA [Bull. 152 The t'liert in j^laces forms massive reefs. Some of these reefs extend for a fow liuiidrctl feet and then gradually diminish in size; others end abruptly and seemingly pass into relatively soft red or white chert. A few masses of chert have been recrystallized and transformed into glauco- phane schist and related schist. These reef like masses may represent hydrothermally altered chert. The Franciscan group in the Ladd-Buckeye region contains fewer igneous rocks than in most other regions. Only three large bodies are present. (1) An irregular body of greenstone, in places parallel to the bedding, is near the Cummings (San Joaquin 3) mine. (2) A sill-like mass of basic igneous rocks lies between the Lone Tree and Tesla faults northwest of Lone Tree Canyon. This mass grades from granophyre at the top down through greenstone, diorite, gabbro, to peridotite at the base. In places it is cut by diabase. (3) A mass of greenstone and grano- phyre is found near the top of the Franciscan near Hospital Creek. A few small outcrops of diabase and greenstone occur in other places. The greenstone is an altered dacite or andesite, and the granophyre is a fine- grained crystalline rock, which in places contains quartz crystals. About 10 miles south of the Ladd-Buckeye area, the Franciscan contains a large mass of basic plutonic rocks.'' On the north side of Sulphur Spring Gulch, about 1 mile south of the Cummings mine (San Joaquin 3), a plug of greenstone protrudes through the strata. The internal structure of this mass of lava resembles pillow lava, a feature ordinarily regarded as being formed by submarine lava flows, but as the greenstone is discordant with the country rock, the mass of greenstone seems to be intrusive. Perhaps the mass has been squeezed differentially through less competent clastic rocks, and is now at a distance from the strata into which it was originally emplaced ; the process possibly being somewhat analagous to the emplacement of salt domes. This differential squeezing of more competent bodies through less competent aggregates of rock, may be more common in the Fran- ciscan than has been generally recognized in the past. Such an explana- tion might account for some of the many isolated blocks of massive rocks, 10 to 100 feet or more in diameter, Avhich form prominent features of the landscape in areas of Franciscan rocks. The sandstone, shale, and chert locally have been metamorphosed to crystalline schist. The types of schist that are present include glauco- ,phane, quartz-albite, actinolite, lawsonite chlorite, muscovite, garnet, acmite, and tremolite schist. The schist is found in aureoles, commonly near serpentine. Most of the aureoles are a few feet to a few tens of feet in length. Near the Ladd mine, phyllite has been formed from shale. The time of formation of the glaucophane schist and related schist, and of the quartz and calcite veins, apparently was Jurassic, as no younger rocks contain them. In places both chert and sandstone are cut by (luartz veins. This quartz veining is most noticeable in chert, in which it commonly forms a network of veins from an eighth to half an inch in diameter. Also, much of the primary manganese ore is cut by similar veins. The greenstone commonly is cut by many calcite veins as much as 4 inches in thickness. Marble, showing crj-^stalline faces up to a quarter of an inch in diameter « Wells, F. G., Hawkes, H. E., and Wheeler, D. P., Chromite and quicksilver deposits of the Del Puerto area, Stanislaus County, California: U. S. Geol. Survey Bull. 936-D, pp. 79-110, 1942. 1950] DESCRIPTION OF DEPOSITS 215 is found in a few places in the Franciscan group, notably in the Ingram Canyon area. The marble is banded and seems to be of vein origin. In the Ladd mine the rhodoehrosite is cut by calcite veins. Horsetown Formation. In the vicinity of Hospital Canyon the Horsetown formation of Lower Cretaceous age overlies the Franciscan group. A thin sandy limestone or calcareous sandstone 50 to 200 feet above the contact carries an ammonite Sonneratia which, according to a per- sonal communication from R. W. Imlay, is characteristic of the upper half of the Horsetown formation. This fossiliferous zone closely parallels the contact with the Franciscan, which suggests that the contact is depositional, and the abrupt change in lithology points to the presence of an unconformity. The Horsetown formation consists of soft sandstone and shale. Along Hospital Canyon it is about 4,000 feet thick, for the first Upper Cretaceous fossils are found 4,000 feet above the base of the for- mation in the matrix of a conglomerate. Panoche Formation. The Panoche formation of Upper Cretaceous age consists of sandstone and shale very similar to that of the underlying Horsetown. The Panoche was not mapped in detail. The formation is more than 5,000 feet thick ; it rests against the Franciscan group by fault contact northwest of Lone Tree Creek ; and in the narrow belt mapped northeast of the Tesla fault, it is overlain by the San Pablo formation of upper Miocene age. San Pahlo Formation. The San Pablo formation consists pre- dominantly of sandstone. The sand grains in some beds are coated with a bluish material said to be the phosphate mineral vivianite, which imparts a distinctive color to the rocks. Quaternary Sediments. The Quaternary deposits consist of land- slide debris and alluvium. All the formations in the Ladd-Buckeye area give rise to landslides. The more prominent landslides have been shown on plate 4. Some of the landslides are clearly related to earlier erosion cycles, and are now dissected materially. The rocks in some areas of moderate and gentle relief are overlain by a mantle of alluvium and rubble which attains a maximum thickness of 20 feet. This alluvial material contains many rock fragments that range in size up to 6 inches. The alluvium seem- ingly was deposited in an earlier cycle of erosion when the relief of the land was less than at present. This alluvium does not erode easily and much of it still persists, even though the main drainage lines are con- siderably below it. In places, particularly around the Ladd mine, it blankets parts of the country so effectively that the nature of the under- lying rocks cannot be determined. Structural Featiires. The Franciscan group has been severely deformed. It stands in steeply inclined beds and is tightly folded in many places. Few distinctive stratigraphie zones or key beds of value for field tracing were found in the area. Consequently structural interpretations must be made from the areal pattern of the lithologic units and the apparent dip of the beds. The problem is complicated further by uncer- tainty as to whether the strata are right side up or are overturned. The prevailing strike is west and northwest. The dip is generally 50° or more northeast, except near the Ladd mine where the dip is west (sec. AA', pi. 4). The rocks in the Ladd area could represent either the north- east limb of the syncline or a section of beds overturned near the Tesla fault. If the beds are not overturned, they probably are on the northeast 216 MANGANESE IX CALIFORNIA [Bull. 152 limb of the syncline mapped east of the Ciimmings mine. If this interpre- tation is true, the ore bods in the T^add and rumniinfrs mines are essen- tially at the same strati^raphic horizon. Two larjre faults, the Tesla and Lone Tree, extend for a lonp: distance in the east part of the Ladd-Buekeye area. The Tesla fault forms the boundary between the Franciscan group and younger formations. East of Hospital Creek Avhere the trace of the fault lies near the fossil bed in the lower part of the Panoche formation, the displacement seemingly is small, but in the north part of the area the displacement apparently is a few thousand feet. The dip of the fault plane where exposed, ranges from 60° SAV. to vertical. As tlie southwest side is the upthrown side, the fault is a thrust fault. The Lone Tree fault is later than the Tesla fault. In the vicinity of Lone Tree Creek the trace of the Tesla fault is offset 1,500 feet hori- zontally by the Lone Tree fault. The Lone Tree fault has been traced more or less definitely for 9 miles from a point 2 miles north of Lone Tree Creek to the east end of the area mapped. The fault plane, where exposed, dips 60° SAY. As the upthrown side is on the west, this fault also is probably a thrust fault. The offset of the Tesla fault indicates that a considerable horizontal component may be present. The displacement seems to be a few thousand feet. The traces of the Tesla and Lone Tree faults are bent toward the north near Hospital Canyon, which may indicate deformation after the two faults were formed. The Franciscan rocks are much crumpled and broken by faults of small displacement, but careful mapping failed to reveal any major faults other than the Lone Tree and Tesla faults. Althcmgh the chert is intri- eatelj^ contorted, especially where it is thin-bedded, many individual chert zones were traced for hundreds or even thousands of feet without being offset materially by faults. The only area in which the Franciscan rocks seem to have been seriously broken by small faults is in Ingram Canyon near the Grummett Knox mine (Stanislaus 11). In this area the structure is more complex than shown on plate 4. To a lesser extent the local structure elsewhere is more complex than can be represented on the map. Many of the small faults in the chert bodies are compression and tear faults. They start with small displacement and within a horizontal distance of 50 to 200 feet build up a displacement of 25 to 50 feet. The compression fault may end in a tear fault or it may continue with diminishing displacement until it merges with the bedding. The chert commonly is interbedded with thin beds of shale, which seem to act as zones of lubrication when the beds are deformed. Normally the chert beds slip over the intervening shale beds Avithout much deformation, but in places local irregularities such as contortions in the chert apparently have impeded slipping along the shale beds, with the result that a break formed and the rocks were pushed over and between adjacent beds for a short distance. Apparently the rocks reacted to structural deformation as incompetent beds, because all the faults are of short horizontal extent and the displacement is small. In the Cummings mine (San Joaquin 3) the deformation came in distinct steps, because in one place two small offsets were formed one after the other, rather than as one larger offset. The generally small displacement of these faults is advantageous to the miner because it lessens the amount of exploration required to find the con- tinuation of ore beds when the ore is truncated by faulting. 1950] DESCRIPTION OF DEPOSITS 217 Physiography. Tlie Tjadd-Buckeye region contains evidence of several cycles of erosion. The tops of the hills are rounded and gently sloping, suggestive of the remnants of an elevated surface of low relief. Benches and terraces on the sides of the valleys point to uplift in steps. Ore Deposits. The manganese deposits in the Ladd-Buckeye area are found exclusively in white chert. The white chert is in two zones of thin-bedded and massive chert, one near the Ladd mine at the north end of the area mapped, and the other near the Buckeye mine, 8 miles to the south (pi. 4). The interval betAveen these two zones contains relatively little chert and no worthwhile manganese deposits. The distribution of the chert strongly suggests that the ore zones at the Ladd (San Joaquin 5), Cummings (San Joaquin 3), Buckeye (Stanislaus 4), and Tip Top (Stanislaus 28) mines are at essentially the same stratigraphic horizon. The Liberty and Moran Brothers mines (Stanislaus 16 and 21) seem to be 3,000 feet stratigraphically above this horizon. The stratigraphic thickness of the ore zones exhibits a crude rela- tionship to the thickness of the chert zones Avhich contain the manganese. At the Cummings mine the ore is found in a stratigraphic zone 65 feet thick and the chert in which this zone lies is 300 feet thick. The respective thickness of the ore zone and the chert section for the Ladd mine are 125 and 600 feet, and for the Buckeye and Tip Top mines approximately 600 and 2,000 feet, respectively ; that is, the ratio of the ore zone to thick- ness of chert in these four mines is of the same order of magnitude, which suggests a genetic relationship between the manganese and chert. The manganese ore forms beds of lenses in bodies of massive white chert, which in turn are lenticular. The ore lenses are roughly elliptical in outline. The general dimensions of the ore beds that have been mined sufficiently to indicate their form are given in the accompanying table. The ore bodies range in length from a few feet to 800 feet, but most of them are less than 200 feet in length. The ratio of maximum diameter to minimum diameter ranges chiefly between 1.3 and 2. The maximum thickness of the mined ore bodies ranges mainly between 4 and 10 feet ; the maximum thickness of 35 feet at the Ladd mine includes some disseminated ore, which has not been mined. The thickness of the deposits is small compared with their length. The ratio of length (greatest diameter) to maximum thickness ranges mainly between 15 and 40. Types of Ore. Two types of ore are found: (1) massive ore, and (2) disseminated ore. The principal primary mineral in the massive ore is fine-grained gray rhodochrosite, having an average grain size of about 0.05 inch, and in the disseminated type it is a mixture of rhodochrosite and bementite (hydrous manganese silicate) disseminated in chert. Some bementite is found in the massiA^e type of ore, commonly in laminae alternating with carbonate. Both kinds of ore are cut by numerous inter- secting veins of quartz and pink rhodochrosite 0.05 to 0.25 inch in thick- ness. In a few places the massive gray rhodochrosite is cut by small calcite veins. Hausmannite, rhodonite, and braunite have been reported from the massive ore beds, but they are not plentiful. Near the surface of the ground, the ore is oxidized to the usual black oxides. The zone of gradation between massive rhodochrosite and wall rock in most deposits is relatively thin, both on the sides and at the ends of the ore bodies. The material in this transition zone consists of rhodochro- site and bementite disseminated in chert. In places near the ends or 218 MANGANESE IN CALIFORNIA [Bull. 152 edges of the ore zones, tlie massive ore prives Avay p:radually to dissemi- nated ore tliroufrhont a distance of several feet. Most ore bodies are blunt and tonj^ue shaped at their ends, thoufjh some of them grade into the wall rock in an interfingering pattern in which mueh bementite is mixed with the chert. In such transition zones, rhodoehrosite is commonly found in spherules and rhombs which have a maximum diameter of a quarter of an inch. The east ore bed at the Ladd mine contains a thick zone of dis- seminated ore above the massive ore. The massive ore ranges in thickness from 2 to 15 feet and the disseminated ore from 1 foot to :}() feet. The grade of ore decreases more or less regularly upward in the deposit. The manganese oxide in the massive ore bodies is similar to the oxide ore in the disseminated ore beds, although in the massive beds the oxide ore commonly is hard and dense; whereas in the disseminated type much of it is soft and powdery, presumably because of its disseminated nature. The manganese in general has not migrated far from its original position, and little ore is found in the wall rocks except for films along fractures. Tahle }. Range in size of manganeae ore bodies in the Ladd-Bucleye and Black Wonder areas, San Joaquin, Santa Clara, and Stanislaus Counties. Name of ore bed Maximum diameter (feet) Minimum diameter (feet) Maximum thickness (feet) Ratio of maximum to minimum diameter Ratio of maximum diameter to maximum thickness Ladd mine (San Joaquin 5) East ore bed West ore bed Cummings mine (San Joaquin 3) North ore bed Middle ore bed South ore bed Buckeye mine (Stanislaus 4) North ore bed South ore bed Liberty mine (Stanislaus 16) Ore body A Ore body B Ore body C Jones mine (Santa Clara 19) . . Murmac (Santa Clara 34) Average (median) 800 170 150 150? 75? 220 125 175 110 40 150 100 .350 + 100 85 75? 50? 200 + 100 75 35 20 110 50 35 4 10 4 4.5 11 9 5 2.5 2.2 2.3 1.8 2.0? 1.5 1.1 1.3 2.3 3.0 2.0 1.4 2.0 23 43 15 37? 17? 20 14 22 37 13 30 40 150 80 1.9 23 Manganese carbonate and bementite oxidize readily to manganese oxides. The chert at the surface of the ground commonly is silicified and the ore is hard and den.se, but Avithin a few feet of the surface the chert is leached. The ore in these leached zones commonly is soft and porous and easily removed with a jnck. In places the silica has been largely dissolved from the wall rocks, leaving a clayey residue. 1950] DESCRIPTION OF DEPOSITS 219 The depth of oxidation in part seems to be related to the ruggedness of the topoo-raphy. In the Ladd, Cununiniis, and Liberty mines, which are located near the crests of rounded hills, the zone of oxidation is more than 100 feet in depth ; however, in the Buckeye mine situated on the side of a steep valley, it is less than 100 feet in depth. At the Acme lode prospect (Santa Clara 1) in the floor of Beauregarde Creek in the Black Wonder area 15 miles south of the Buckeye mine, rhodochrosite is found within 1 foot of the surface of the ground. Consequently, in appraising reserves of ore in undeveloped prospects one should bear in mind that the ore may pass into primary carbonate and bementite within a rela- tively short distance if the deposits are located on the sides or in the bottom of canyons. The original manganese carbonate in places has been altered by hydrothermal solutions, as is attested by the quartz veins that cut it; by the presence of small amounts of cinnabar in the ore at a few places, notably in the Liberty mine and the north ore body at the Buckeye mine ; and by the lack of bedding and uniform grain size of the massive gray rhodochrosite. The presence of hausmannite, rhodonite, and braunite also suggests hydrothermal alteration. The hydrothermal action, how- ever, probably has not caused the manganese to migrate far, because all of the deposits that were seen are essentially parallel to the bedding and hence seem sedimentary in origin. Grade of Ore. The grade of the massive ore is fairly high. The beds of primary carbonate commonly contain from 35 to 42 percent manga- nese, and 10 to 15 percent silica. The oxides derived from such deposits by weathering have from 50 to 55 percent manganese, and from 10 to 20 percent silica. The banded bementite and carbonate deposits have from 25 to 35 percent manganese, and from 15 to 30 percent silica. The dis- seminated deposits have from 5 to 25 percent manganese, and from 30 to 60 percent silica. Thus, manganese and silica vary inversely with each other. Except for silica, the ore contains no undesirable impurities. Iron ranges mainly between 0.5 and 1.5 percent, phosphorus between 0.02 and 0.06 percent, and sulphur between 0.01 percent and 0.03 percent. Origin. The origin of the manganese deposits is intimately associ- ated with the deposition of the chert. No ore body in the Ladd-Buckeye area is found in rocks other than white chert. In Humboldt County in northern California, manganese in places is found in alternating red shale and chert in the Franciscan group. In the Ladd-Buckeye region some of the massive white beds contain ore that grades laterally into thin- bedded white and red chert within a distance of a few hundred feet, but the ore invariably is associated with the white chert, and in most places with massive white chert. The stratigraphic distribution of the chert suggests that the chert beds are laid down in basins on the sea floor. The way in which the zones of chert and associated sediments pinch and swell along the strike and their lenslike shape, supports such a concept. Moreover, many of the beds of white chert in which the rhodochrosite is found, are included in zones of red chert, which in turn are lenticular masses in sandstone and shale. The red color of the chert suggests an advanced state of oxidation, and the presence of manganese carbonate indicates a state of retarded oxidation, or more appropriately a state of relative reduction. Manganese in the form of rhodochrosite is in the lowest oxidized state for manganese. 220 MANGANESE IN' CALIFORNIA [Bull. 152 A pro<;ressive deoxidation of the sediments fT'om red chert to manga- nese t-arbonate, therefore, is suirjiested. A favoi-able place for the devel- oimient of a state of reduction is in basins on the sea floor, where tiie water is relatively deficient in oxyjien. Sediments in basins are deposited under more reduced conditions than sediments that accumulate in adjacent shallower ymrts of the sea.'^ Tlie lack of higher oxides in manp:anifei"ous white chert accordinprly su('aurejrarde Creek in see. 28, and tlie other near the Black Mike claim (Stanislaus 2) in sec. 14. In places the greenstone is vesicular, which suggests that some of it is derived from flows; but on Beaurogarde Creek where well exposed, it is intru- sive. At the east end of the Cottonwood claim (Santa Clara 11 ) the green- stone cuts bementite and rhodochrosite in chert, apparently without altering these minerals. The primary manganese minerals therefore are earlier than this particular greenstone. The plutonic rocks that intrude the sandstone and shale in the north- east part of the area have been described by "Wells, I lawkes, and Wheeler.^ These rocks are largely altered to serpentine, and they contain deposits of chromite on Adobe Creek and of magnesite on Red Mountain. They do not seem to be related to the manganese in the Puerto Creek area, although in the Antonia deposit (Santa Clara 3) in sec. 32 to the south- west, alteration associated with serpentine has profoundly modified the chert in which the manganese is found. Glaucophane and associated schists are found only in the southwest part of section 32. The usual types of schist of the Franciscan are present : glaucophane, quartz-albite, lawsonite, chlorite, and actinolite. At the Antonia claim a large block of magniferous chert near the east border of the schist mass, adjacent to a serpentine contact, has been partly recrys- tallized to quartz-araphibole schist in Avhich bementite and rhombs of manganese carbonate have been observed. The regional strike is northwest. Most of the beds dip 45° to 70°. Exposures are so poor that the structure cannot be ascertained with certainty, even in areas where trenches have been dug. In places, particu- larly in the Jones mine (Santa Clara 19) , the beds have been badly broken by faults, but the displacement of most of the faults is less than 50 feet. At this locality most blocks larger than 6 inches in diameter have been fractured. In other areas the strata continue for at least 100 feet without being broken. A zone of chert extends almost uninterruptedly, except for minor faults, from the Jones mine to the Murmac prospect, along the ridge forming the boundary between Santa Clara and Stanislaus Counties. Minor folds lie on the flanks of this ridge. The manganese ore is in irregular lenses in Avhite chert. The high- grade ore consists almost entirely of manganese minerals, and the low- grade ore is an intimate mixture of chert, quartz, and manganese minerals. This second type, called stock work ore, grades into the first, and a tran- sition zone of it borders the high-grade bodies. The primary mineral in the high-grade ore is gray rhodochrosite, which looks like dirty loaf sugar. The average diameter of the mineral grains is about one-sixteenth inch. The primary minerals in the low-grade ore are honej' -brown man- ganese silicate and rhodochrosite. This honey-broAvn mineral looks like bementite. Identification has not yet been verified by means of X-ray diffraction patterns, but the mineral is designated as bementite in this section of this report. The color grades from honey-broAvn to light gray or to white, which suggests that chert grades into bementite and that the bementite is of sedimentary origin. In places, both chert and bementite contain spherical or ellipsoidal segregations of rhodochrosite about a swells, F. S., llawke.s, H. E., and Wheeler, D. P., Chromite and quicksilver deposits of the Del I'uerto area, Stanislaus County, California: U. S. Geol. Survey Bull. 936, pp. 79-110, 1942. 1950] DESCRIPTION OF DEPOSITS 245 sixteenth to a quarter inch in diameter. In other places, rhombs of car- bonate, presumably rhodochrosite, of similar size, are enclosed in chert. Near the surface of the ground, the primar^^ minerals have been oxidized, but the relationship of the various oxides to the primary min- erals is obscure. The manganese in most places has migrated very little, though cracks and fissures near the manganese deposits commonly are stained with thin films of manganese. The depth of oxidation does not correspond closely to the surface topography, as can be seen in the winze at the Jones mine (Santa Clara 19). The boundary between primary and oxide ore lies at a depth of 50 feet in the winze, whereas in the drift northward from the winze into the heart of the mountain at a level of 63 feet, the boundary is below the floor of the drift. The change from oxide to carbonate in the winze takes place mostly within 5 feet, but long tongues of oxide extend along fractures for at least 25 feet below the main zone of change. The ore in several prospects, but particularly at the Jones mine, is cut by an interlocking network of thin quartz veins. In the oxidized zones the presence of these quartz veins imparts a box-work appearance to the ore. In the Ladd-Buckeye area to the north in San Joaquin and Stanislaus Counties, these quartz veins are associated with pyrite and a mineral that looks like cinnabar. This relationship suggests that the veins are of hydrothermal origin. At the Jones group, the rhodochrosite is very even- grained and gives no indication of stratification, which suggests that the hydrothermal action that formed the quartz veins also may have reworked the rhodochrosite. In this area the manganese oxides have penetrated the wall rock more than in places where the quartz veins are less plentiful. ]\Iany of the high-grade deposits have a hanging wall of massive white chert and a footwall of thin-bedded buff chert. A similar relation was noted in the Ladd mine (San Joaquin 5) to the north. As the strata do not seem to be overturned, the ore bodies are interpreted as lying at the base of massive beds of white chert. Many of the better lenses of ore terminate bluntly against white chert along the bedding, the massive white chert occupying space that would be taken by ore if the ore con- tinued. The primary minerals, therefore, seem to have been formed by the same general processes that formed the massive white chert, but under special local environmental conditions. The detailed stratigraphic map- ping in the Ladd-Buckeye area suggests that these special conditions prevailed in basins on the sea floor where the oxygen content of the water was particularly low. Description of Manganese Deposits No. 1. Acme Lode Claim. (By Parker D. Trask and Frank S. Simons, October 1941.) The Acme Lode claim is on the north side of Beauregarde Creek in the NW^ sec. 30, T. 6 S., R. 5 E. (pi. 11, deposit 12). It is 1 mile east of the .junction of the Puerto Creek road with the Livermore-Mount Hamilton road. The claim was located by James Renfrew, J. W. Bonsack, and Ralph Bolt, on January 18, 1941. Develop- ment consists of a shaft 3 feet deep, two open cuts, and five trenches. The ore bed is exposed for 125 feet, mostly in the bed of the creek. It strikes northwest and dips 40° to 75° NE. The average width is 3 feet and the maximum is 4 feet. The ore consists mainly of siliceous oxides in white chert, but in the creek bottom rhodochrosite is found. The grade varies, 246 MANGANESE IN CALIFORNIA [BuU. 152 but is richest toward the southeast end, where it is of the order of 25 percent manganese. The ore at the north end is of low grade, probably about 4 percent manganese. No. 2. Ala Mountain Mine. (Modified slightly from original description in California Min. Bur. Bull. 76, p. 75, 1918.) The Ala Mountain mine is 26 miles southeast of Livermore in sec. 28, T. 5 S., R. 4 E. A body of manganese ore about 4 feet wide is exposed in an open cut and short tunnel. Some ore was hauled to Livermore prior to Worhl War I. The Merchant Estate of Livermore is the owner. No. 3. Antonia Claim. (By Frank S. Simons and Parker D. Trask, October 1941.) The Antonia claim is on the south side of Beaure- garde Creek in sec. 32, T. 6 S., R. 5 E. (pi. 11, deposit 2). It was located by Matt Keller on February 25, 1940. The main exposure of manganese material is in a broken block of massive chert, 100 feet in diameter, known locally as the "Big Blowout. " Four small trenches have been dug around this body of chert. The deposit is of little economic interest for most of the manganese is in thin films of oxide or in disseminated manganiferous carbonate. The manganese content is approximately 10 percent. The chert is almost completely recrystallized to quartzite. The chert body is adjoined by serpentine derived from pja'oxenite on the east, and by glaucophane, crossite, and related schists on the west. The chert exhibits contact metamorphie development of glaucophane, crossite, albite, garnet, and apatite common to the altered chert of the Franciscan group, as well as the very unusual development of abundant acmite and less abundant aegirine. This mineral assemblage indicates that considerable soda has been added hj^drothermally to the chert. No. 4. Avery Prospect. (From files of U. S. Geological Survey, 1918.) A deposit said to be owned bj' George D. Avery of Porterville is located 25 miles from Livermore in Santa Clara County. A sample of ore assayed 35 percent manganese and 12 percent silica. The exact location of the deposit is unknown. No. 5. Billy Goat Prospect (Wasp-K.H.D.). (From files of U. S. Geological Survey, 1918.) A deposit knowni as the Billy Goat or Wasp- K.H.D. prospect is 25 miles southeast of Livermore in sec. 12, T. 6 S., R. 4 E. It is said to be owned by John Pattner of Livermore and to have produced 49 tons in 1917. No. 6. Black Bear Mine. (California Min. Bur. Bull. 76, p. 75, 1918.) "Black Bear Mine, 25 miles southeast of Livermore, is in sec. 34, T. 5 S., R. 4 E., near the summit of the west slope of the Arroyo Mocho Valley, at an elevation of 3100 feet. Interbedded lenses of manganese ore OQCur in the jasper, some of them being 3' in thickness and fairly exten- sive. Development consists of several open cuts and tunnels. The property has been idle for several years. D. P. Doak, Rialto Bldg., San Francisco, is the owner. ' ' No. 7. Blaclhird (Blackhawlx) Claim. (By Frank S. Simons and Parker D. Tra.sk, October 1941.) A claim presumed to be the Blackbird lies on the same ridge as the Mexican prospects (Santa Clara 30) in the northeast part of sec. 28, T. 6 S., R. 5 E. (pi. 11, deposit 6). The o^vne^ is M. E. Fisher. Two trenches expose a bed of siliceous manganese oxide 70 feet long. The maximum width is 4 feet and the average width 2 feet. The ore is discontinuous and variable in grade. In places it is found in pockets which range in size from 2 to 4 feet. The ore is richest at the 1950] DESCRIPTION OF DEPOSITS 247 south end where it contains as much as 30 percent manganese. The aver- age grade is under 25 percent manganese. The ore body strikes northwest and dips 60° to 85° SW. It is terminated on the south by a fault and 22 feet north of the south end it is offset 8 feet by another fault. Prospect- ing for the continuation of the ore beyond the fault at the south end would be difficult because of the depth of overburden. No. 8. Black Eagle Claim. (By Frank S. Simons and Parker D. Trask, December 1941.) The Black Eagle claim is on the south side of Beauregarde Creek 0.3 mile west of the May Be claim (Santa Clara 27), in the SE^ sec. 28, T. 6 S., R. 5 E. (pi. 11, deposit 8). It was located by Mrs. Antonia Harris on July 16, 1940. It is leased to the Barker Corpora- tion. Production to November 15, 1942, was 40 tons shipped to the General Dry Battery Plant at Patterson. Development consists of an area 300 feet long and 150 feet wide, which has been scraped with a bulldozer, and two open cuts. The U. S. Bureau of Mines has also opened two cuts along two of the ore bodies. Ore is exposed in two places in the bulldozed area. At the discovery monument a mass of ore has a strike length of 40 feet. The ore is siliceous manganese oxide, very discontinuous and uneven in tenor. It is associated with greenstone and altered greenish sandstone, but the field relations are obscure. The bed strikes N. 30° W. and dips about 20° SW., but the dip is not clear. The greatest width of ore is 5 feet. Some of the high- grade ore is associated with greenstone and altered sandstone and is traversed bj^ many quartz veinlets. It may have a hydrothermal origin, as silica is abundant and some of the nearbj* shale is chloritized, but too little development has been done to prove or disprove this. About 125 feet southeast of the first exposure of ore is a body of high-grade ore 10 feet long and 4 feet wide, which the U. S. Bureau of Mines uncovered. The associated rocks are greenstone and altered shale, but the exposures are too poor to indicate the relationships. This body evidently is not connected with the ore to the northwest, as the inter- vening rocks are purple and buff shale. The best ore here may contain as much as 40 percent manganese. The ore at the main outcrop averages about 25 percent manganese. Further development should be done on the high-grade ore at the southeast end of the area, but lack of outcrops in the immediate A^einity would make additional prospecting futile. No. 9. Black Horse Claim. (By Parker D. Trask and Frank S. Simons, December 1942.) The Black Horse claim is in the NE^ sec 32, T. 6 S., R. 5 E., on the southwest side of Beauregarde Creek about 500 feet southeast of the junction of the north and south forks (pi. 11, deposit 3). The claim was located by Mrs. Antonia Harris on November 28, 1939. The claim is leased to the Barker Corporation. The production to November 15, 1942, was 40 tons, shipped to the General Dry Battery Plant at Patterson. Three open cuts and two trenches delimit the ore body. The ore is mainh'' low-grade oxide with relatively high silica content, but there are a few pockets of high-grade oxide, the largest of which is 4.5 feet in diameter. The manganese ore is confined to a bed which strikes N. 25°-45° W, and dips 65° to 85° N. The hanging wall is red shale over- lain by massive white chert, and the footwall is massive white chert stained with manganese oxide. The ore body is exposed for 120 feet and attains a maximum width of 5 feet. It pinches out to the northwest. The southwest end is not exposed, but where last seen has thinned to 2 feet 248 MANGANESE IN CALIFORNIA [BuU. 152 and probably does not continue much larther. The o;rade of the ore varies considerably along the strike but averages about 20 percent manganese. No. 10. Cedar Tree Claimfi. (By Prank S. Simons and Parker D. Trask, December 1941.) The Cedar Tree claims are on the south side of Beauregarde Creek in sec. X\, T. 6 S., R. 5 1]. (pi. 11, deposit 1). One claim ill the name of Mrs. Antonia Harris extends 1,100 feet east of the discovery monument and the other in the name of Matt Keller runs 1,200 feet north from the same discovery monument. Both claims were located January 20, 1941. Development consists of five trenches and one cut. The cut is 50 feet long and 10 feet wide. The ore body consists of disseminated oxide in white chert. It is exposed for a distance of 50 feet and has a maximum Avidth of 2 feet. It is displaced by several faults of small throw. On the north side, the ore body lies nearly parallel to the surface of the ground, dipping 15° N., but on the south side it is folded into a sharp anticline and presumably thins out a short distance beneath the surface of the ground. The footwall is shaly chert and the hanging wall is thin-bedded brown chert. Above the footwall is at least 4 feet of low-grade ore. The manganese oxides in this ore zone probably are derived from the overlying ore body. No. 11. Cottonwood Claim. (By Frank S. Simons and Parker D. Trask, December 1942.) The Cottonwood claim (pi. 11, deposit 10) is on the north side of Beauregarde Creek in the SW:i sec. 28, T. 6 S., R. 5 E., 0.3 mile Avest of the Triple Jump claim (Santa Clara 4). It was located by Matt Keller, June 25, 1940, and is leased to the Barker Corporation. Production to November 15, 1942, was 40 tons sold to the General Dry Battery plant at Patterson. An area 300 feet long and 100 feet wide has been scraped by a bulldozer, and in addition four cuts and trenches have been opened. Ore is exposed in two places. At the northwest end of one open cut, a series of blocks of siliceous manganese oxide, 2 to 5 feet wide, are exposed throughout a distance of 40 feet. The trend of the blocks is N. 30° W., and the dip is nearly vertical. These blocks may be faulted segments of a single bed. They are associated with greenstone and are cut by many small quartz veins. Some of the adjacent shale has been chloritized. The relation of the greenstone to the manganese material is obscure, but the chert in which the manganese is found has been altered hydrothermally. The grade of the ore varies but the average is about 35 percent manganese. Another ore body, 10 feet long and 5 feet wide, is exposed at the southeast end of the open cut. The ore strikes north and is nearly vertical. It is adjacent to a greenstone bod}^ 5 feet thick, and in one place it is cut by a thin stringer of greenstone, which seemingly has not altered the manganese minerals. This bed is stratigraphically distinct from the first bed, as the intervening rocks are well exposed in the cut and no fault is apparent. The grade likewise is higher; the average is 40 percent manganese. The extent of this ore body has not been determined as it strikes into the hill, but it warrants further testing because the width and grade are relativelj^ high. No. 12. Davenport Prospect. (By E. F. Davis, October 1, 1917.) The Davenport i)rospect is owned bj' J. W. Davenport of Livermore. It is about 500 feet south of the center of the north line of sec. 27, T. 5 S., K. 4 E., about half a mile east of the Arroyo Mocho road. A lens of mas- sive ore 5 feet thick is enclosed in red radiolarian chert and shale. The 1950] DESCRIPTION OF DEPOSITS 249 beds strike N. 70° W., and dip 65° S., parallel to the ore body. The ore is highl}^ siliceous and is cut by numerous veins of quartz. No. 13. Davenport and Smith Property. (By E. F. Davis, Octo- ber 1, 1917.) A prospect owned by Davenport and Smith of Livermore is half a mile off the Arroyo Moeho road, 25 miles southeast of Liver- more, in the NE^ sec. 27, T. 5 S., R. 4 E. It lies on the south slope of the ridge that occupies this quarter section. The ore body is exposed in a number of workings. At the extreme northwest end of the property, an inclined shaft follows the ore bed down dip for 25 feet. Southeast of this point the ore body is exposed in a series of open trenches. Ninety feet southeast of the shaft is a drift which runs nearly northeast along the strike of the ore body for a distance of 35 feet. Southeast of this drift are other trenches along the course of the ore body. At the extreme southeast end of the property, 300 feet from the shaft, a short tunnel exposes 5 feet of ore. The ore body is a massive bed of siliceous manganese oxide. It strikes N. 50° W., and dips from 25° to 75° SW. It is considerably broken by minor shearing so that the relations to the country rock are not clear. Where undisturbed it is parallel to the bedding of the enclosing chert and shale. The thickness of the ore body averages 2.5 feet. The maximum thickness is 6 feet. In the shale are several thin beds of siliceous ore which have the same relation to the shale that chert ordin- arily has. These beds are about 3 inches in thickness and are composed of the same material that is found in the larger ore bod3^ No. 14. DeForest Prospect. (Modified slightly from original description in California Min. Bur. Kept. 13, p. 507, 1896.) A pocket of manganese ore is found in sec. 12, T. 7 S., R. 4 E., in a ravine 3 miles south of DeForest, at an altitude of 2.500 feet. The property is undevel- oped, but is said to contain 57 percent manganese. No. 15. Doak No. 2 Prospect. (Modified slightly from original description in California Min. Bur. Bull. 76. p. 77, 1918.) The Doak No. 2 prospect is in the Red Mountain district, 25 miles southeast of Livermore on the Camp Bessie road, in sec. 22, T. 5 S., R. 4 E. A few open cuts and short tunnels have been driven on massive outcrops of manganiferous chert, exposing a vein of manganese ore said to be 4 feet in width. A few tons of ore were produced from this deposit, but it is now idle. D. P. Doak of San Francisco is the owner. No. 16. Fable Mine (Camp Bessie). (By F. S. Hudson, October 1, 1917.) The Fable or Camp Bessie mine is said to be the property of Tom Green. It is about 300 j'ards west of the Arroyo Mocho road, 26 miles southeast of Livermore in the SW^NE^ sec. 34, T. 5 S., R. 4 E. A small gulch passes a few yards south of the mine and enters the Arroyo Mocho a few hundred yards to the east. The approximate altitude of the mine is 2,850 feet. A tunnel has been driven N. 40° W. into the hill. It follows the ore body for 30 feet to a fault which strikes N. 20° E., and cuts off the ore bed. The tunnel turns here and follows the fault for 30 feet, at which point the ore body was again found. A drift follows the faulted portion of the ore for 10 feet in a direction N. 70° W. A considerable amount of ore has been removed by open cut stripping just outside the mouth of the tunnel, and a narrow stope connects the tunnel with the surface. 250 MANGANESE IN CALIFORNIA [Bull. 152 The ore body is a massive bed of oxide ore lying conformably within a series ol" tliin-bedded chert and shale. The rocks dip 45° to 65° S. The ore consists of manganese oxides and silica. Most of the ore is compact, bnt mnch of it is cellnlar; the irregular cavities commonly being lined with drusy masses of reddish iron-stained material. By hand sorting, pieces of ore free of apparent silica, up to 3 inches in diameter, may be obtained, but considerable iron is present throughout. Some process of enrichment seems to have acted, which removed silica but left the iron and manganese behind. That part of the ore body which is east of the fault has been exposed for about 75 feet along the strike, and for 25 feet above the workings. Its thickness ranges from 4 to 6 feet, averaging about 5 feet. That part of the ore bed which has been shifted to the north on the west side of the fault is exposed for 15 feet along the drift and averages 2.5 feet in thickness. Examiiuition of the exposures in the creek bed about 60 feet west of the face of the drift, showed only sandstone, apparently because another cross fault displaces the ore bed between the face of the drift and the creek bed. At the time of the examination, work was being started to cut the extension of this body at a point about half way betM^een the fact of the drift and the creek, by crosscutting from near the mouth of the tunnel. No. 17. Frankel Prospect. (By Spangler Ricker, 1941.) The Frankel prospect is 6 miles east of Berryessa in T. 6 S., R. 2 E., on the Frankel Ranch. The deposit consists of stains of manganese oxide, and is of little value. No. 18. Great Expectation Mine. (By E. F. Davis and F. S. Hud- son, September 27, 1917.) The Great Expectation mine is on property of E. P. Newhall of Livermore, in sec. 36, T. 5 S., R. 4 E., on one of the head waters of Colorado Creek. It is reached by following the Arroyo Mocho road from Livermore for 29 miles, where the road leaves Colorado Creek to climb over a low divide into the drainage of San Antonio Creek. A branch road goes up Colorado Creek from this point to Newhall 's camp, about 3 miles distant. Two definite zones of ore are exposed on the property; these are about 100 feet apart stratigraphically. The north- easterly and lower of these zones has been worked the most. A short drift follows the ore and a crosscut was being driven to intersect the ore beyond the face of the drift. The work on the southwest body con- sists of a small amount of stripping to remove surface rock. The northeast ore body is a massive lens, lying within bedded radio- larian chert and shale, parallel to the bedding. The general strike is N. 70° W., and the dip 45° S. The chert above the ore bed is white and pink. In places it is thin-bedded, at other places massive, the change being accomplished by a wedging out at the ends of chert lenses. The ore body is underlain by thin-bedded green shale and chert. The contact of the ore against the enclosing chert is sharp. The ore body for the most part is composed of manganese oxide and of patches of residual silica. However, carbonate ore is found in the bottom of the drift. The carbonate has been oxidized along joint cracks so that ore breaks out in blocks apparently composed of oxide through- out, but on cracking these blocks the unoxidized kernel of pink or brown carbonate is found. The carbonate is composed of gray ore, pink crystal- line rhodoehrosite, and a brown carbonate, determined in the field to be 1950] DESCRIPTION OF DEPOSITS 251 siderite. These minerals show a rude alteration in bands. Locally the siderite occurs as spherules in the midst of the other carbonates. The silica content of the ore varies greatly. A rather interesting feature of this occurrence is the presence of small spherules of rhodochrosite in some of the bedded chert on the hanging-wall side of the ore body. As suggested above, the oxidation of such spherules may account for the slight manganese oxide staining in the Avail rocks. In this ore body the carbonate ore lies 5 to 10 feet above the bed of the creek, which is dry in the summer. The level of the ground water is uncertain, but the upper limit of the carbonate is certainly above the present ground-water level. The ore body is exposed from near the creek level to a point about 60 feet to the northwest, where it lenses out. Its maximum thickness is 2.5 feet, gradually thinning to zero at the northwest end. The southwestern ore body is a massive bed of chert enclosed in bedded chert and shale with apparent conformity. The bed has altered in part to a manganese oxide ore, carrying skeletons of residual silica, and in part to a mixture of manganese oxide and of silica, clearly pseudo- morphous after a chert carrying spherules of manganese carbonate. This bed ranges from 7 to 10 feet in thickness and is exposed in several places for a distance of 300 feet along the strike, which swings from N. 60° W. at the southern end to N. 20° W. at the northern end. The dip ranges from 45° to 65° SW. Insufficient work has been done on this bed to permit estimating either grade or tonnage. A picked sample ran 40 percent manganese and 16 percent silica. Exploration might prove the presence of considerable amounts of ore here. No. 19. Jones Deposits. (By Frank S. Simons and Parker D. Trask, December 1942.) The Jones group of prospects in the NW^ sec. 27, T. 6 S., R. 5 E. (pi. 11, deposit 20), are the largest and best explored in the Black Wonder area. They have been operated by the Western Man- ganese Company. Of the five deposits (pi. 12) , deposit I has been explored the most extensively. A tunnel 50 feet in length was driven before 1910. These workings were extended in the winter of 1940 and the spring of 1941, and approximately 400 tons of high-grade oxide ore was shipped. Subsequently a winze and additional workings at a depth of 63 feet were opened. The other deposits have been prospected by numerous trenches, as shown on plate 12. The geology of these deposits is shown on a topographic map (pi. 12) . As the outcrops are poor, the position of the contacts and the structure of the rocks could be ascertained only in a general way. A body of chert 250 feet thick lies within a sandstone sequence. The sandstone beneath the chert seems to grade into thin-bedded shale and chert toward the west. The general strike is northwest and the dip is 50° to 80° SW. A few minor folds and wrinkles are present. The structure in the main level of the Jones mine at deposit I is complicated, as illustrated by plates 13 and 14, but at depth in the winze, the strata are persistent for 100 feet, except for one horizontal fault having a displacement of 3 feet. The ore at the Jones group of prospects is found in massive white chert embedded in thin-bedded red chert and shale. It is of three types. In the Jones mine, it consists of high-grade massive black oxide in beds 3 to 5 feet thick. At a depth of about 50 feet in this mine, the black oxide 252 MANGANESE IN CALIFORNIA [BuU. 152 grades into rhodoehrosite. In the other deposits the ore is low-grade siliceous black oxide. At deposit I there are two and probably three ore bodies within a stratigraphic range of 35 feet (pis. 13 and 14). The ore body that yielded most of the ore is folded into a tight anticline, and is cut by numerous faults. This faulting has caused the ore to occur in blocks. The general trend of the axis of the anticline is N. 60° W. The ore in the west limb of the anticline does not extend beyond a depth of 60 feet below the floor of the adit, as the east drill holes at that level in the winze did not disclose manganese ore. The extent of the east limb of the anticline is unknown. About 25 feet northeast of this ore body, a small amount of man- ganese oxide was taken from an open cut. The ore body here pinches out with depth, and almost certainly is not connected with the main ore body in the mine. Ten feet stratigraphically above the main ore body is another lens of ore, which ranges in width from 3 to 5 feet. It terminates bluntly in the roof of the main workings. Approximately 75 tons of ore have come from this lens. The lens has been followed downward in a winze to a depth of 85 feet and at this depth shows no indication of becoming thinner ; so it presumably must continue for at least an additional 25 feet. The ore was followed for 145 feet in the two drifts at the 63-foot level, before it pinched out. The probable limits of the ore body as defined by the exploratory work are shown in plates 13 and 14. The outline is roughly elliptical. The major axis is 155 feet in length, and the minor axis 115 feet. The ratio of the tM'o axes is 1.3 :1, and the ratio of the long diameter to maximum thickness is 31 ;] . Deposit II is the longest ore body in the Black Wonder area. It can be traced in a northwesterly direction for 310 feet though its course is sinuous and it is offset by several faults having displacements of less than 50 feet. The dip is nearly vertical. The average thickness is 2.5 feet, and the maximum thickness is 6 feet. In one trench the walls of the ore body expand downward, which suggests that the lens may get wider with depth. It probably does not extend much beyond a depth of 60 feet, for the drill hole into the wall of the winze at a depth of 60 feet in deposit I, encountered only 2 feet of low-grade manganese ore at a distance of 30 feet from the winze. This zone of low-grade manganese may repre- sent the downward continuation of deposit II, for on the surface of the ground, deposit II lies 50 feet stratigraphically above the west ore body in deposit I. The ore in deposit II varies considerably in grade, but the average is of the order of 20 percent manganese. Deposit III crops out in two places 30 feet apart, and presumably is continuous between these two exposures, except for minor faults. The strike is northwest and the dip nearly vertical. About 2.5 feet of high-grade manganese oxide are seen in a small drift and crosscut at the southeast end of the ore body. At the north end the lens is 4.5 feet wide. The walls are slightly fractured, but they diverge downward, which suggests that the surface exposures may be the upper part of a lens. Hence, a considerable tonnage of ore may be present. The average grade is about 40 percent manganese. This deposit illustrates the desirability of exploring manganiferous lenses in massive cliert. At the outcrop the ore was only 3 inches wide; at a depth of 4 feet it was 4.5 feet wide; and presumably below it is 1950] DESCRIPTION OF DEPOSITS 253 thicker. Apparently the surface exposure was just the tip of an ore body, ' just as at the west ore body in the Buckeye (Stanislaus 4) mine to the north. Deposit IV, 40 feet south of deposit III, is 25 feet long and averages 1 foot in width. It probably is faulted at both ends. The average grade is about 35 percent manganese. Its position with respect to deposit III suggests that it is in the same stratigraphic zone as deposit II, which is less than 50 feet above the west ore bed at deposit I. Deposit V is exposed in three cuts. It is 60 feet long and 2 to 5 feet wide. The bed is vertical at the west end and dips 60° S. at the east end. The wall rocks are shaly chert. The average grade is of the order of 25 per- cent, but some of the ore is high grade. No. 20. Keller Brothers Prospect. (By E. F. Davis and F. S. Hudson, September 30, 1917.) Keller Brothers own a prospect of man- ganese ore on their ranch in San Antonio Valley in sec. 13, T. 6 S., R. 4 E. No ore has been produced and only a little development has been done. The prospect was not visited. No. 21. Keller Mine (Dead Oak). (By Parker D. Trask and Frank S. Simons, December 1942.) The Keller mine is in the northwest part of sec. 32, T. 6 S., R. 5 E., and 'is operated by the Barker Corpora- tion (pi. 11, deposit 4). The total production through 1941 was 756 tons, of which 54 tons was produced in 1940, and 702 tons in 1941. The 1942 production, up to November 15, was 938 tons, sold to the General Dry Battery plant at Patterson. The ore body trends N. 30° W. and is nearly vertical. Before the mine was worked the surface exposures consisted of a mass of black oxide 6 feet wide and 15 feet long. This body increased in size downward, and at a depth of 15 feet was 12 feet wide. Below a depth of 20 feet it began to thin and at a depth of 35 feet had almost pinched out. The maximum length of the ore in the workings was 35 feet. Later the mine was reopened and explored, and an ore body 6 feet thick was found at the bottom of a 125-foot inclined shaft, in a drift 60 feet long. The ore body was separated from the wall rock, whicli consisted of leached thin-bedded chert. The presence of a fine clay zone along the walls suggests that the ore body is limited by faults. The chert zone in which the ore is found can be traced for 100 j'-ards to the south, where it abuts into a large mass of glaucophane schist. On the north this chert body presumably is cut off by a fault within 50 feet of the mine, for in the road cut just north of the workings, sandstone lies in the projection of the ore body. No. 22. A. M. Kelley Prospect. (By E. F. Davis, November 3, 1917). The A. M. Kelley prospect is on land owned by A. M. Kelley of Morgan Hill, in lot No." 16, map No. 3, Morgan Hill Ranch, in T. 9 S., R. 3 E. The property is not being operated at present. It is 2 miles south- west of Madrone on a low ridge at the head of a small flat-floored valley, tributary to the Santa Clara Valley. The prospect is 1,000 feet southwest of the Morgan Hill prospect (Santa Clara 32), south Avcst of the State Highway between INIorgan Hill and j\Iadrone. It is reached by a road which is' within 1,000 feet of the prospect. Development consists of three open cuts. The area west of ]\Ir. Kelley 's house consists principally of radio- larian chert, much of which is thin-bedded and of intrusive greenstone 254 MANGANESE IN CALIFORNIA [BuU. 152 and serpentine. At several places the chert is brightly colored as a result of the contact action of these igneous rocks, and in some places it is stained ' with manganese oxide. The massive cliert is cut by numerous fissures filled by oxides of manganese which form stains and impregnations. Only a few pounds of commercial ore are in sight here. Most of the mate- rial is too siliceous to be worked. No. 23. Kellcy Prospect. (By E. F. Davis and F. S. Hudson, September 29, 1917.) The Kelley prospect is owned by Ed Kelley, Mrs. Plattner and William Hampton. It is the NW^ sec. 12, T. 6 S., R. 4 E., at an altitude of 3,220 feet, 31 miles from Livermore and 0.3 mile east of a branch road that runs up Colorado Creek to the Newhall mine. The ore is exposed in a small open cut for a distance of 15 feet. The ore body is enclosed within well-bedded radiolarian chert and shale which range in color from red to salmon, and the beds strike approximately east and dip 85° N. The ore body pinches and swells, ranging in thickness from 1 foot to 3.5 feet. It is massive and rather siliceous. A few small spherules of manganese carbonate embedded in a matrix of chalcedonic silica were .seen. In many places the carbonate has been leached, leaving small round holes. All the ore exposed is siliceous and averages over 25 percent silica, with 5 to 15 percent iron, and 20 to 35 percent manganese. No. 24. Lopez Prospect. (Modified slightly from original descrip- tion in California Div. Min. Kept. 26, p. 14, 1930.) Alfred Lopez of Morgan Hill, reports a manganese deposit, probably in sec. 19, T. 9 S., R. 3 E., 1 mile west of Madrone Station on the Rainey Ranch. No. 25. Mammoth Mine. (By E. F. Davis and F. S. Hudson, September 30, 1917.) The Mammoth mine is owned by H. H. Ballentine and is leased to John Plattner. It is 0.8 mile east of the Arro^'o Mocho road 32 miles southeast of Livermore, on one of the tributaries of San Antonio Creek. The mine is in sec. 13, T. 6 S., R. 4 E., on land originally taken up as a mining claim by Mrs. Augusta Jones. Development con- sists of several open cuts all of which expose massive siliceous oxide ore. The ore bodies, although varying considerably in thickness, are thought to be parts of a single bed, dipping in general to the northeast, but warped and broken by minor faults. The thickness ranges from 3 to 6 feet. At one place a lens of chert 1.5 feet thick is interbedded in the ore body. No. 26. Mateos Ranch Deposit. (Modified slightly from original description in California Min. Bur. Bull. 76, p. 78, 1918.) The Mateos Ranch deposit is in sec. 8. T. 6 S., R. 2 E., 8 miles by road east of IMilpitas, in Alum Rock Canyon, about 2 miles beyond the park. It is owned by John D. Mateos of San Jose. The manganese ore occurs in seams and pockets in chert. Considerable high-grade float is found in the canyon, and a few large boulders aggregating several tons in weight are in a small ravine near junctions with the main canyon. The ore, however, is intermixed with chert, and is low in grade. A tunnel was driven 40 years ago in tlie chert, and some high-grade ore is said to have been shipped. The tunnel is now caved. About 200 feet west of the tunnel and at the same elevation, an open cut was made in 1917, and about 40 tons of ore was shipped. The face of the cut is slumped, so Ihat no ore is now exposed. No. 27. May Be Claim. (By Frank S. Simons and Parker D. Trask, 1941.) The May Be claim is on the north side of Beauregarde Creek in the SE^ sec. 28, T." 6 S., R. 5 E. (pi. 11, deposit 7). It was located by Mrs. Antonia Harris. Two cuts and a trench have been opened. The ore 1950] DESCRIPTION OF DEPOSITS 255 is exposed intermittently over a distance of 90 feet. The ore body strikes northwest and dips 25° NE. It probably is cut by faults at each end. The ore consists of low-grade oxides in massive white chert. The chert has been partly recrystallized and is cut by many quartz veins, suggestive of hj'drothermal alteration. At the south end the manganese content is about 20 percent, and at the north end it is 10 percent or less. No. 28. McCoy Deposit. (From files of U. S. Geological Survey, 1942.) A deposit controlled by C. L. McCoy of San Jose produced 15 tons of ore containing 31.6 percent manganese in November 1942. The ore was shipped to the General Dry Battery plant at Patterson. The location of the deposit is unknown but is believed to be near San Jose. No. 29. McPherson Prospect. (From files of U. S. Geological Survey, 1942.) In 1942, J. L. McPherson delivered 8 tons of ore contain- ing 35.9 percent manganese to the General Dry Battery plant at Patter- son. The location of the deposit from which the ore came is not known. No. 30. Mexican Deposits. (By Frank S. Simons and Parker D. Trask, December 1941.) The Mexican group of deposits is on the ridge between the two forks of Beauregarde Creek in sec. 27, T. 6 S., K. 5 E. The deposits are leased to the Western Manganese Company. Three ore bodies are present (pi. 11, deposits 5a, 5b, 5c). Thej' lie along the regional strike over a distance of 1,000 feet, but do not appear to be at the same strati- graphic horizon. No claim notices were found. At the first deposit (5a), a shaft has been sunk 35 feet in white chert, exposing a body of ore which is 2 feet wide near the surface and pinches out at a depth of 16 feet. The ore bed cannot be followed on the surface. The ore is black oxide in white chert, and the grade is of the order of 25 percent. The ore body strikes east and is nearly vertical. The north wall is thin white chert succeeded by thin brown chert. The south wall is white chert. By analogy with other deposits, the south wall should be the upper side of the deposit. At the second deposit (5b), three open cuts expose a steeply dipping bed of siliceous manganese oxide ore, 3.5 feet wide and 75 feet long. The grade of ore varies along the strike, but the average tenor of manganese is 10 percent or less. The third deposit (5c), is the most promising of the Mexican group. Six open cuts and a shaft 7 feet deep have been opened. The ore is siliceous manganese oxide in white chert. It is exposed in a lens 120 feet long and 6 feet in maximum width. The average width is 4 feet. The ore body pinches out at each end but widens downward. The strike is approxi- mately north and the dip nearly vertical. At the north end it dips 75° E., and at the south end it dips 70° W. The ore body is offset by several small faults. The tenor varies along the strike. At the south end low-grade stockwork ore is present. The average grade is about 25 percent man- ganese. A second bed of siliceous manganese ore 2 feet wide and 25 feet long is found 20 feet south of the shaft. Its manganese content is about 10 percent. No. 31. Miller Prospect. (From files of U. S. Geological Survey, 1918.) A deposit said to be owned by Caldwell and Albrecht and leased to a Mr. Miller, is reported to have produced 189 tons of ore containing 35 percent manganese and 12 to 17 percent silica in 1918. Its location is unknown. 256 MANGANESE IN CALIFORNIA [Bull. 152 No. 32. Morgan Hill Prsopect. (By E. F. Davis, November 3, 1917.) Tlie Morgan Hill Prospect is on the Morgan Hill Water Works property in T. 9 S., R. 3 E. It adjoins the KelU'v place on the north, and the workings are about 1,000 feet northeast of the A. ]\I. Kelley prospect (Santa Clara 22). The deposit is on the northeast side of a small ridge which rises from a flat-bottomed valley. The Avorkings are 2 miles south- west of Madrone and 500 feet from the road. The property is under lease to Eaton and Company, but is now idle. The workings have caved, so no good sections of the ore are exposed. The lower part of the ridge on which the deposits occur is composed of serpentine and greenstone. The upper part consists principally of red chert and shale stained with manganese oxide. In this chert are several bodies of siliceous ore. In a few places the contacts have been sheared and faulted, and in two places greenstone is faulted against the ore. The ore is siliceous and probably exceeds 25 percent silica. The property produced 70 tons of shipping ore before it was abandoned. No. 33. Mt. Hamilton Prospect. (By Spangler Ricker, October 1941.) The Mt. Hamilton prosi)ect is near Lick Observatory in T. 7 S., R. 3 E. The owner is H. Backman of Berkeley. The ore body is exposed for a distance of 100 feet and has an average width of 7 feet. The grade is estimated to be 10 percent manganese. It has produced no ore. No. 34. Murmac Group. (By Frank S. Simons and Parker D. Trask, 1941.) The Murmac group is in the westernmost series of deposits along the ridge between Santa Clara and Stanislaus Counties. The group is in the SWj sec. 21, T. 6 S., R. 5 E. (pi. 11, deposit 18) . Five claims cover the area : Murmac, Murmac No. 1, Murmac No. 2, Patterson, and Chicago. The locators of the first three claims are not known. The owner of the Patterson claim is A. II. Jones, and of the Chicago claim, B. E. Cronk- heit. In addition, two other claims have been located, one by Mary Lou Smith, December 2, 1940, and the other by Lee Neideffer, date unknown. The Murmac group of deposits produced 224 tons of manganese in 1941. Five ore bodies are present in the Murmac group. Deposit 1 is the main ore body and lies at the west end of the area; deposit 2 is in the ravine 125 feet east of the east end of deposit 1 ; deposit 3 is on the hill- side 100 yards east of deposit 2 ; deposit 4 is a large boulder of high- grade manganese on top of the main divide, 150 yards north of deposit 3 ; and deposit 5 is on the main divide 100 yards west of deposit 4. The rela- tionship of these deposits to the surrounding rocks is shown in plate 15. The West Coast Chrome Company opened deposit 1 in a cut 110 feet long and 10 feet deep. The U. S. Bureau of Mines sank one inclined shaft 25 feet down the dip of the ore body in this cut to where the ore was truncated by a fault, and another, 15 feet deep along the continuation of the ore body beyond the fault. In addition the U. S. Bureau of Mines dug 51 trenches. The rocks consist of zones of chert and sandstone, which seemingly grade into one another within a very short distance. The region is faulted considerably, but most of the faults seem to have displacements of 25 feet or less. All the manganese deposits may lie at essentially the same strati- graphic horizon, but because of the poorness of the exposures no such inference is demonstrated. They could equally well occur at different horizons. At deposit 3 a massive white chert lens lies 35 feet above the ore bed. It is stained by manganese in places and may indicate the presence 1950] DESCRIPTION OP DEPOSITS 257 of a second ore zone, which is not well developed at this locality. Similarly deposit 2 may represent a zone a similar distance below deposit 1, but in view of the poorness of the exposures no definite statement can be made. The ore beds are lenses in white chert. They are bedded deposits, though the surface exposures at deposits 1 and 2 are cut by numerous small quartz veins which suggest hydrothermal alteration. The ore con- sists of siliceous black oxides in white chert. The hanging wall is massive white chert and the footwall is buff thin-bedded chert. The ore bodies are lenticular and near where they pinch out, become relatively siliceous. The ore is of the stockwork type ; the grade of the deposits is not high, except for deposit 4, which runs 45 percent manganese or better. At deposit 1 in the open cut the average grade is 35 percent manganese, and in the second shaft near where the ore pinches out it is 15 percent man- ganese. The grade at deposit 2 is variable but is of the order of 25 per- cent manganese. The other two deposits probably contain less than 10 percent manganese. Deposit 3 contains the longest ore body, 125 feet in length. Its aver- age thickness is 4.5 feet, and its maximum width is 6 feet. The ratio of length to maximum width is 21 : 1. The next largest ore body is in deposit 1. This ore body is exposed in the open cut for 110 feet, and it pinches out at each end. It can be traced down the dip in the inclined shafts for 40 feet before it grades out. The maximum thickness is 2.5 feet and the average is 2 feet. The ratio of maximum length to maximum thickness is 42 : 1, and the ratio of long diameter to short diameter is about 2 : 1. Deposit 2 is exposed for 25 feet, and has a maximum thickness of 5 feet and a minimum of 2 feet. The ore body is seemingly offset by faults, but its continuation could not be found. In the cut 20 feet west of the ravine, the ore bed is duplicated by faulting. Deposit 4 is an erosional remnant of a once much larger body. It consists of a block of black oxide cut by many quartz veins. This block is estimated to weigh 150 tons. Deposit 5 consists of two beds 50 feet apart, each about 1 foot thick, exposed for a distance of 40 feet. No. 35. Newsom Prospect. (By Frank S. Simons, October 6, 1942.) The Newsom prospect is in the SEi sec. 26, T. 5 S., R. 4 E., 3 miles by road from the Arroyo Mocho road and 26 miles from Livermore. It is on land owned by Archie Newsom of Livermore, and leased by J. J. Kenney of San Francisco. A large area at the top of a low ridge has been thoroughly bulldozed. Blocks of siliceous ore are scattered over the entire area. The ore occurrences trend north. At the south end an open cut 70 feet long exposes massive white chert carrying thin films of manganese oxide. About 25 tons of ore are in sight, averaging 15 percent manganese. A deep bulldozer cut across the south end of the working shows only thin-bedded red chert, striking N. 50° E., and dipping 30° SE., demonstrating that the white chert pinches out or is faulted off at the south end of the cut. The floor of the cut is not exposed, but it is thought that the manganiferous white chert does not persist to any great depth. The manganiferous chert can be traced for 30 feet beyond the north end of the cut, where a bulldozer trench shows that the ore body either lenses out in thin-bedded shaly chert or, more likely, is faulted off. The manganiferous chert crops out again 40 feet farther north, and can be traced more or less continuously for 80 feet, at which point a deep trench exposes an extremely faulted 9—11208 258 MANGANESE IN CALIFORNIA [BuU. 152 and brecciated mass of brown and white chert enclosing a very irregular ore body. The chert strikes N. 30° W., and dips 5° to 45° NE. The ore bed exposed in the north wall of the trench, 10 feet deep, apparently ranges from 2 to 11 feet in thickness. The ore here averages 20 percent manganese. One hundred feet north of tliis trench is the last exposure of ore, in an old cut. Another trench here shows that the ore body is not persistent, and lenses out downward into shaly chert. Some of the ore in the cut contains 25 to 30 percent manganese, but probably little mate- rial of this grade is present. All the available evidence points to a rather shallow deposit, because at no place does the ore extend down for more than 10 feet. The country is highly faulted and brecciated, and much of the ore appears to have been concentrated in the brecciated parts of the chert. No. 36. Pennsylvania Deposit (Nolle Lease). (By E. F. Davis and Frank S. Hudson, September 30, 1917.) The Pennsylvania deposit is on the southwest side of San Antonio Valley in the SW| sec. 12, T. 7 S., R. 4 E., and is reached by the Arroyo Mocho road on a road through San Antonio Valley. It is owned by M. ]\I. 'Day of San Jose and is under lease to the Noble Electric Steel Company. Work on this property has been discontinued recently. The production was 200 tons in "World War I. The property has been explored in three places. The southern and northern workings are on a body of folded and contorted radiolarian chert 30 feet wide. The southern working is an open cut just south of a small creek, which crosses the body of cliert. The ore lies in a massive bed which is enclosed in and is parallel to well-bedded radiolarian chert and shale. These beds vary from white and gray to pink and red. The average strike is N. 15° W., and the dip is 65° to 70° SW. Both strike and dip vary considerably because of the folding of the cliert. The ore body ranges in thickness from 6 inches to 2.5 feet. It is siliceous and is mixed with much massive red chert. In places it contains small sheaves of an acicular green mineral not yet identified. The northern working lies just north of the creek. Here small open cuts run into the chert and into the enclosing sandstone, but all the ore here has been removed, and to judge from the size of the workings no important ore body was found. One hundred and fifty yards down the creek, to the east of the chert body above described, a cut has been made along the contact of chert and sandstone. The creek below the cut is full of siliceous ore that has been blasted out and thrown into the creek. No ore remains in the workings and nothing is left to suggest the original relationships of the ore. The ore here is brown to black siliceous oxide. It leaves a porous residue on treatment with acid. The ore material is cut by veinlets of unidentified pale pink columnar hydrous silicate of manganese and contains masses of a granular pink manganese silicate, occurring in scalj^ aggregates which have not been identified. No com- mercial ore is left on this property and there appears no good prospect of discovering more ore, though additional prospecting might be justified on an outcrop of siliceous ore soutli of the south working. The outlook here is not promising because the ore is siliceous. No. 37. Pine Richje Mine. (By Frank S. Simons^nid Max D. Crittenden, Jr., October 24, 1942.) The Pine Ridge mine is in sec. 31, T. 8 S., R. 4 E., on the McDermott Ranch, 12 miles northeast of Morgan 1950] DESCRIPTION OF DEPOSITS 259 Hill. It is held under a mineral lease by Alfred Jackson of Morgan Hill. The road to the mine is in very good condition. The first 4 miles after leaving Highway U. S. 101 are paved ; the next 4.4 miles are a gravel surfaced dirt road; and the last 8.6 miles are a good dirt road. The mine is located on the crest of a low knob on Pine Ridge. Outcrops are few. Exploration is being carried on by removing the overburden with a bulldozer. There are a number of separate ore bodies shown in figure 7, which will be described separateh^ The relations of the various ore bodies are not clear, as the bulldozing has scattered ore and country rock over a wide area. All the mining is now being done at ore body No. 1, where a bed of manganese oxide ore 3 to 4 feet thick is exposed for a distance of 175 feet. Outcrops are discontinuous but the ore bed seems to follow an arc striking N. 60° W. at the west end, and X. 10° E. at the east end. Accord- ing to the operator of the mine, the ore body at the original ground surface was nearly parallel to the surface of the hill, but at the depth now exposed dips more steeply than the slope of the hill. Some ore is scattered throughout the area enclosed by the arc of the ore bed, but the rocks are so mixed it is difficult to determine much about them. Both walls of the ore body are broAvn thin-bedded shaly chert. The ore forms a heavy stockwork with cores of spongy red clay apparently representing leached chert. The ore mineral is principally a blue-black oxide with a brownish black streak, and usually 4 to 5 in hardness. Some soft ore is present. The average ore here contains about 85 percent manganese, and can be easily sorted to 40 or even 45 percent manganese. Ten tons of ore are on the dump, containing 40 to 45 percent manganese. Ore body No. 2, situated 400 feet northwest of the east end of ore body No. 1, reveals a bed of manganese oxide ore which strikes west. The wall rocks are red chert and buff shaly chert, but the walls were not exposed at any place, so the thickness of the ore bed is not known. At the east end of the exposure the ore is siliceous, and contains numerous pockets of high-grade ore Seventy feet from the east end, 6 feet of ore is exposed. The ore consists of a peculiar wormy stockwork in vari- colored massive chert. The ''worm holes" are cores of leached chert, often roughly tubular with diameters of a quarter to a half inch. The ore mineral is a bluish-black oxide, varying in hardness from 3 to 6, but usually 3 or 4. The streak is dark brownish black, and the mineral is apparently amorphous. This ore averages 80 to 35 percent manganese, but breaks well and can be easily sorted to 40 percent manganese. About 35 tons averaging 80 percent manganese are piled on the dump. The ore at the west end is siliceous and is difficult to sort to 35 percent. Fifty tons of siliceous ore, averaging 15 to 20 percent manganese, are piled on small dumps. The bed here is at least 8 feet thick. Ore body No. 3 is 60 feet north of the east end of ore body No. 2. It contains an ore bed which strikes N. 75° "W. for 100 feet in a series of disconnected outcrops. The bed is nowhere exposed entirely. It is 2 feet thick at the west end and dips steeply south. The footwall is thin-bedded red chert and the hanging wall is thin-bedded buff and red shaly chert. The ore is crudely laminated and consists of layers of hard, blue-black oxide Cpsilomelane?) up to 1 inch thick alternating with thin layers of chert and shale. Eight tons of ore averaging 40 percent manganese are piled nearby. The average grade is 35 to 40 percent manganese, and little 2(j0 MANGANESE IN CALIFORNIA [Bull. 152 ,.>•<"'""/, EXPLANATION h\ EZ] jO [Chert ond sholy cherlj < Monganese ore Pione toblt iu'vey bf Fronk s 3imons ond Mo« CnMjnden, jr Octobf, 1912. Cc'cjf initrvjl 10 le»l Figure 7. Geologic and topographic map of the Pine Ridge mine, Santa Clara County, California. 1950] DESCRIPTION OF DEPOSITS 261 sorting is needed to raise the ore to this grade. One hundred feet west of the west end of ore body No. 3, several large boulders of high-grade oxide ore have been uncovered by the bulldozer. These boulders seem to repre- sent the continuation of ore body No. 3. Ore body No. 4 is 100 feet north of the west end of ore body No. 3. It consists of a bed of " wormy " ore 100 feet in length, striking N. 75° E., and dipping 50° S. The ore bed is 3 feet thick at the only place where it is exposed. The ore averages 25 to 30 percent manganese, but can easily be sorted to 35 percent and probably to 40 percent. Five tons of sorted ore are on the dump. Ore body No. 5 is 350 feet south of ore body No. 1. It consists of a more or less continuous bed of oxide ore striking N. 30° E. The ore is on the southeast side of a prominent chert bed. The thickness of the ore bed is not known. Most of the ore is siliceous and contains 20 to 25 percent manganese, but numerous blocks of ore containing 30 to 45 percent man- ganese are scattered about the cut. Five tons of ore averaging 35 percent manganese are piled near the cut. x\t the west end of ore body No. 5 is a pile of 5 tons of ore collected from the surface of the ground during World War I. The ore consists of small fragments of chert cemented by manganese oxides. A little botryoidal psilomelane is present, which probably represents a surface concentration of oxides leached from the underlying rock. The ore aver- ages 35 percent but some is 45 percent manganese. Ore body No. 6 is 300 feet west of ore body No. 1. It consists of a bed 6 feet thick in shaly chert striking east and dipping 35° S. The ore is siliceous manganese oxide. It is exposed for 25 feet along the strike in two open cuts. A manganese zone is exposed 250 feet S. 30° W., from ore body No. 1. It is associated with fine-grained sandstone and shale striking N. 45° E. These rocks overlie a series of thin-bedded and massive white and brown chert beds. Locally the shale contains as much as 40 percent man- ganese. The best ore appears to be concentrated in a shaly material similar to that commonly forming partings in chert. The ore is a soft oxide best described as wad. It evidently is the result of concentration of manganese oxide by surface waters, as the best ore appears at or near the surface. Several springs are nearby, one of which is uphill from the deposit. Yery little development has been done and the tonnage to be expected is small. The average grade of this wad -like ore is about 15 percent manganese. Only a small amount of the ore at this locality con- tains as much as 30 percent manganese. This deposit is promising. It contains several ore beds, some of which are fairly thick. The ore is of moderate or good grade and much of it can be sorted to good grade. Past production is reported as 101 tons in 1941 and 325 tons in 1942. The grade of the ore that has been mined averaged 38 percent. One mile west of the main Pine Ridge mine, a series of open cuts exposes manganese oxide ore. The easternmost cut reveals 2 feet of black oxide ore dipping vertically and striking west. The walls are thin-bedded shaly chert. The ore is soft, has a black streak and probably contains considerable manganese dioxide. The bed is exposed for 6 feet along the strike, the western extension being buried by bulldozing. This ore con- tains 35 to 40 percent manganese, but the amount in sight is small. About 100 yards to the northwest are two open cuts along a massive chert bed 262 MANGANESE IN CALIFORNIA [Bull. 152 20 feet thick. The chert strikes N. 55° W., and dips 65° SW. One car of higli-fjrade oxide ore has been shipped from the cut on the southwest side of the massive cliert, but the ore lens has pinched out in the face of the cut and very little ore is exposed in the floor. Five tons of siliceous ore containing 10 to 15 percent manganese are on the dump. A small amount of ore has been removed from the northeast side of the massive chert body. Another 125 feet along the strike to the northwest, a thin bed of oxide ore is exposed in an open cut for a distance of 50 feet. The hanging wall consists of 4 feet of massive white and green chert overlain by thin- bedded buff chert ; the footwall is massive white chert. The ore bed strikes N. 45° W., and dips 50° SW. The bed was 12 to 18 inches thick, and has been nearly completeh^ mined out. The ore holds tightly to the footwall and is difficult to mine. About 25 tons were removed, the ore being blue- black oxide containing approximately 45 percent manganese. The ore is vnggy; many A'ugs contain quartz crystals coated with shiny man- ganese oxide. Some 75 feet northwest along the strike and across a small canvon, 15 tons of ore have been removed from a pocket. The rocks strike N. 25° W., and dip 60° SW. The hanging wall is thin-bedded shaly buff chert, the footwall massive brown and white chert. The southeast end of the ore lens is faulted against brown sandstone. Very little ore remains in sight in the cut. The ore contains about 35 percent manganese. These cuts are all along the same general line, and the ore probably occurs at essentially the same horizon, but the amount of manganese ore at any place is small. The deposit is not now being worked, as there is little ore remaining in any of the cuts. No. 38. Pulse Prospect. (By Frank S. Simons, October 6, 1942.) The Pulse prospect is in the SW^ sec. 26, T. 5 S., R. 4 E., 2 miles by road from the Arroj^o Mocho road and 25 miles southeast of Livermore. It is owned by Jack Pulse of Livermore, and was operated by him for a short time during 1918, A partlj^ caved shaft and road cut show white chert and decomposed buff shaly chert striking N. 30° W., and dipping 50° SW. The chert encloses a body of siliceous manganese oxide ore 2 feet thick at the only place where any ore remains. The ore consists of slightly oxidized pinkish chert containing small pockets of good-grade manganese oxide. The ore is partly exposed along the strike for 35 feet. It apparently lenses out at the north end and is covered by overburden at the south end. The ore now exposed does not contain over 25 percent manganese, and practically none is in sight. According to Mr. Pulse, the shaft was formerly 25 feet deep, and showed a bed of ore 15 feet thick. Some ore, averaging 48 percent manganese, is said to have been shipped, but no ore of this grade is in sight now. The amount of ore remaining at depth is not known. Six hundred feet east of the shaft there is an open cut 60 feet long in thin-bedded brown shaly chert, which carries thin films of manganese oxide. The chert strikes north and dips 25° E. One bed of massive chert contains about 15 percent manganese, but the amount of ore of this grade is small. No. 39. Queen Bee No. 1 (Alma) Claim. (By Frank S. Simons and Parker D. Trask, December 1942.) The Queen Bee No. 1 claim is on the west end of the ridge between Jones and Beauregarde Creeks in the SWi see. 29, T. 6 S., R. 5 E. (pi. 11, deposit 11) . It Avas located by Calvin 1950] DESCRIPTION OF DEPOSITS 263 McMillian on February 27, 1941. It is leased to the Barker Corporation. The production in 1942, up to November 15, was 45 tons. The ore was delivered to the General Dry Battery plant at Patterson. An adit 10 feet long, two open cuts, and two trenches have been opened. The manganese consists mainly of stockwork in white chert, but some ore is massive. The ore bed strikes northwest and dips 65° SW. to vertical. It is 100 feet long and has a maximum width of 6 feet. It widens gradually from a feather edge at the southeast end to 6 feet at the northwest end and then within a distance of 8 feet thins out abruptly. The walls converge downward, and not much ore can be expected at depth. The grade decreases gradually toward the southeast. In the adit at the north end of the ore body the manganese content is about 30 percent, whereas at the southeast end it is approximately 15 percent. No. 40. San Jose Deposit (Penitencia Creek). (Condensed from original description in Rogers, A. F., An interesting occurrence of manga- nese minerals near San Jose, California : Am. Jour. Sci., 4th ser., vol. 48, p. 443, 1919.) A huge boulder of manganese ore formerly was situated in Alum Rock Park along Penitencia Creek in sec. 27, T. 6 S., R. 2 E., 5 miles east of San Jose. The entire boulder was broken up during 1918 and yielded 329 tons of ore. No ore now remains. The ship- ments ranged from 43.2 to 63.5 percent manganese, and contained about 3 percent silica. The minerals according to Rogers are pyrochroite (Mn(0Ii)2), tephroite (Mno04), hausmannite (Mn304), ganophyllite (7MnO.Al2O3.8SiO2.6H2O), rhodochrosite, psilomelane, and barite. No. 41. Triple Jump Claim. (By Frank S. Simons and Parker D. Trask, December 1942.) The Triple Jump claim is on the north side of Beauregarde Creek 1,000 feet west of the location monument of the Black Eagle claim (Santa Clara 8), in SW^ sec. 28, T. 6 S., R. 5 E. (pi. 11, deposit 9). It was located by Walter J. Schroeder on September 9, 1940. The ore is siliceous manganese oxide, 2 feet wide, in white chert adjacent to a greenstone body 30 feet thick. The grade is of the order of 10 percent manganese. An area 300 feet long and 100 feet wide has been scraped by a bulldozer, and in addition, four cuts and trenches have been made. Ore is exposed in two places. At the northwest end of the open cut, a series of blocks of siliceous manganese oxide, 2 to 5 feet wide, are exposed over a distance of 40 feet. The trend of the blocks is north 30° W., and the dip is 20° SW. These blocks are associated with greenstone and are cut by many small quartz veins. Some of the adjacent shale has been chloritized. The relation of the greenstone to the manganese is obscure, but the chert in which the manganese is found has been altered hydrothermally. The grade of the ore varies ; the average is 25 percent manganese. Another body of ore, 10 feet long and 4 feet wide, is exposed at the south end of the open cut. The associated rocks are greenstone and altered shale, but the exposures are too poor to indicate the relationship. The grade of the ore here is about 40 percent manganese. No. 42. Turner Deposit (Black Beauty, Summit). (From files of U. S. Geological Survey, 1917.) The Turner, Black Beauty, or Sum- mit deposit is 27 miles southeast of Livermore in the NE^ sec. 26, T. 5 S., R. 4 E. The owners are Robert and George C. Turner. A considerable tonnage of siliceous ore is said to be present. Production of 50 tons is reported for 1917. 264 MANGANESE IN CALIFORNIA [Bull. 152 No. 43. Wallace Ranch. (Modified slightly from original descrip- tion in California Min. Bur. Bull. 76, p. 79, 1918.) On the Wallace Ranch in sec. 8, T. 6 S., R. 2 p]., 6.5 miles by road east of Milpitas, is a small outcrop of high-jzrade manganese ore. Mrs. Grace P. Wallace of San Jose, is the o-v\nier. This deposit lies southeast of the Mateos Ranch pros- pect (Santa Clara 26), and is evidently a continuation of the same ore body. The chert here crops out prominently in bold ledges over large areas, but for the most part is free from manganese stains. The ore is exposed for a width of 12 inches in a small cut, about 100 feet above the old tunnel on the Mateos ranch. Ore taken from this deposit is reported to have assayed 50.8 percent manganese. No. 44. Winegar Mine. (By Frank S. Simons, October 7, 1942.) The Winegar mine is in sec. 19, T. 5 S., R. 4 E., 5.1 miles by road from the Arroyo Mocho road and 27 miles from Livermore. It is on land owned by the K. D. Winship Estate, and is leased by Phil Winegar of Vernalis. The ore is found in two beds of siliceous manganese oxide separated along the strike by 80 feet of barren chert. The upper ore bed is exposed in an open cut 70 feet long, and its average thickness is 4.5 feet. The strike is N. 45° W., and the dip is 60° SW. The bed lenses out abruptly 10 feet from the northwest end of the cut, but can be traced southeast of the cut for 150 feet. At its southeast end it is 2.5 feet thick, strikes N. 60° W., and dips 60° NE. Thirty feet below the cut a tunnel 70 feet long has been driven along the strike. The ore body pinches out abruptly almost directly below the point at which it terminates in the cut above. The ore in the tunnel averages 4 feet in thickness. The strike is N. 30° W., and the dip 60° SW. The ore bed is remarkably uniform in thickness. The ore at the surface is being carefully hand sorted, and is some- what higher grade than the ore in the tunnel, where surface waters have not been able to leach the silica so thoroughly. The average grade of the ore at the surface is 20 percent manganese, and in the tunnel, 15 percent manganese. The ore is sorted so as to yield more than 35 per- cent manganese. Eighty feet northwest of the tunnel portal, a second open cut exposes a bed of siliceous manganese oxide ore 60 feet long and ranging in thickness from 3 to 6 feet. The ore bed is enclosed in shaly chert striking N. 30° W., and dipping steeply northeast. The face of the cut is 25 feet high. The ore is of the same character as that in the upper cut and tunnel, averaging 15 to 20 percent manganese. The ore bed lenses out to the northwest and appears to be faulted off at the southeast end. Thirty -five tons of sorted ore are on the stock pile, averaging about 35 percent manganese. Total production to November 15, 1942, was 299 tons, averaging 35 to 40 percent manganese. This ore has been sold to the General Dry Battery stock pile at ]*atterson, and shipping costs have ranged between $4.50 and $5.00 ])er ton. / No. 45. Winship Leases (Aitkcn-Wolfe). (By Frank S. Simons, June 10, 1942.) A. C. Aitken and F. L. Wolfe of San F'rancisco have leased two manganese prospects in sec. 27, T. 5 S., R, 4 E., on land of the K. D. Winship Estate. This prospect is 25 miles by road from Liver- more, and was operated by Ilolbrook and McGuirre during the last war. The predominant rock of the area is massive leached white chert, Avliich seems to strike north. Practically no rock can be seen in place, and 1950] DESCRIPTION OF DEPOSITS 265 attitudes are uncertain. Enclosed in this chert is a poorly defined bed of oxide ore of unknown thickness, which can be traced for 40 feet on the surface. The ore grades into massive chert to the north, and the south end is buried. Most of the ore is very low in grade, containing about 15 percent manganese and much silica, but some ore contains 35 percent manganese. The relations of ore to country rock in two open cuts are not clear, as the cuts are partly caved. A tunnel that was driven in 1918 from a point 150 feet west of the ore bed is said to have extended beyond the projected position of the ore bed at a depth of 30 feet below it, without encountering ore. The ore thus does not seem to persist to any great depth, as is also suggested by the irregularity of the surface exposures. The only good ore occurs near the surface or at the surface, w^here much of the silica has been leached, leaving skeletons of silica and manganese oxides. A few feet below the surface the silica is porous but less leached than at the surface, and at a depth of 10 feet the ore is low in grade and siliceous. The deposit is said to have yielded 125 tons in World War I and has produced 12 tons in World War II. A second deposit in the SE^ sec. 27, T. 5 S., R. 4 E., is 24 miles by road southeast of Livermore. The area is very hea^dly covered wdth brush and only a few exposures are visible. The predominant rock of the area is thin-bedded red chert, which strikes about east. Three outcrops of siliceous manganese oxide ore have been exposed by shallow cuts. The westernmost outcrop shows 5 feet of siliceous ore in white chert striking N. 60° W., and dipping 25° SW. Fifty feet east an outcrop of similar rock strikes east and dips 60° S., and 60 feet east of this another exposure of chert, with some manganese oxide films, strikes N. 70° W., and dips 45° SW. These outcrops appear to be parts of a more or less continuous bed of siliceous manganese oxide ore. The best ore seen does not contain over 25 percent manganese, and the average grade of all ore is about 15 or 20 percent manganese. Very little development work has been done, so the character of the ore at depth remains unknown, but, by analogy with other deposits of a similar type, it is thought that the ore at depth will be more siliceous and lower in grade than the well oxidized part of the ore bed at the surface. One hundred ten feet below the ore bed a tunnel 210 feet long was driven into the hill to tap the bed at depth. This tunnel exposes a white and green chert interbedded with shale, striking N. 55° W., and dipping 30° to 50° SW. No ore of any kind is exposed in the tunnel, which is considerabh^ longer than should have been necessary to reach the ore bed. Thus, barring considerable faulting, which is not evident in the tunnel, the ore bed can be assumed to lens out before reach- ing 110 feet in depth. This prospect is not considered promising, as the grade of the ore is very low. However, a considerable tonnage may be present, if a market for the available grade of ore materializes. SHASTA COUNTY No. 1. Arps Prospect. (From files of U. S. Geological Survey, 1918.) A deposit owned by C. L. Wilson of San Francisco is located near Copper City, 5 miles from Heroult, probably in T. 33 N., R. 4 W. It is said to be 1,200 feet in length and 125 feet in thickness. The prospect was not visited but by analogy with deposits in this general area, the grade is likelv to be low. 266 MANGANESE IX CALIFORNIA [BuU. 152 No. 2. Duncan Creek Prospect. (From files of U. S. Geological Survey, 1918.) A deposit located in T. 30 N., R. 8 W., west of Ono on Duncan Creek, is said to be owned by the American Manganese Mining and Smelting Company. Other details are lacking. No. 3. Exposed Treasure Barite Prospect. (From files of U. S. Geological Survey, 1918.) The Exposed Treasure Barite prospect, located in the southwest part of T. 36 N., R. 1 W., is said to contain manganese. No. 4. Goat Camp Claim. (By Parker D. Trask, August 1942.) The Goat Camp claim is situated at an altitude of about 5,000 feet near the west boundary of Sliasta County in the SW^ sec. 36, T. 29 N., R. 11 W. The deposit is located along the side of a forest road, 60 miles from Red Blulf, the nearest rail point. Two claims trending north and south were taken out by G. E. Riemert and TV. 0. Friend of Hayfork. Develop- ment Avork consists of two shallow pits about 5 feet in diameter. The ore occurs in a small chert body enclosed in greenstone. The ore minerals in order of quantity present, are rhodonite, bementite, and rhodochrosite. The size of the ore bodj^ is about 4 by 4 feet, and there is little reason to believe it is more extensive, as the chert in which it lies is completely surrounded by greenstone. The grade of the ore is estimated to be about 30 percent manganese, but the total reserves are probably less than 20 tons. No. 5. Nicol Deposit. (By Parker D. Trask, August 1942.) The Nicol deposit is in the SWl sec. 22, T. 29 N., R. 9 W., 2 miles south of Platina and 45 miles from Red Bluff, the nearest rail station. It is sit- uated on the side of a steep mountain about 1 mile by trail from the nearest road. The deposit is reported to be on fee land owned by Mrs. E. M. Nicol. One cut 8 feet deep has been opened, presumably in World War I. No ore has been shipped. The deposit is in massive chert which strikes N. 85° E., and dips nearly vertically. The ore body lias a maxi- mum width of 5 feet and can be traced for 50 feet. About 100 yards across the strike to the north the chert is succeeded by greenstone. The ore consists of low-grade oxide estimated to contain between 10 and 15 per- cent manganese. By analogy with rocks in the same geologic setting, the primary ore is manganiferous chert and perhaps rhodonite. No. 6. Nigger Hill Claims. (By Ivan F. Wilson, July 25, 1942.) The Nigger Hill claims are 11 miles west of Ono. They are reached by driving along the road west of Ono for 7.7 miles, then turning north along a branch road for 3.2 miles to the top of a ridge. Some ore has been developed at this point, but the main workings are 1,700 feet to the east along the ridge. The altitude is about 2,800 feet. The nearest shipping point is Redding, 28 miles distant, but the ore is now being hauled to Anderson, 32 miles east. The last 3.2 miles of the road are steep, but the road is in good condition. The property comprises four claims, occupying 480 acres. It embraces the W^EJ, and the W^ sec. 14, T. 30 N., R. 8 W. The claims are owned by Glen Murphy of Ono, and are being operated by Kuppinger & Pinkham of Lakeport. Wlien the main workings were visited, a cut across the ore bed had just been opened to depth of 1 foot to 2 feet. A quarter of a mile down the slope to the northeast is an ofd shaft 10 feet long by 3 feet wide, 20 feet deep, which exposes the manga- nese-bearing rock. The manganese ore occurs in beds of lenses of fine-grained quartzite or quartz schist, which seems to be recrystallized chert. Tlie chert is enclosed in a quartz-rich medium-grained (luartz-muscovite-biotite 1950] DESCRIPTION OF DEPOSITS 267 schist which consists of qiiartzose layers separated by finer layers of mica. This schist is in an area indicated on the State Geologic map ^ as "Pre- Cambrian metamorphics. " Both the metachert and enclosing schist are cut by quartz veins 3 to 4 inches thick. At the main workings in the eastern part of the property, near the crest of the ridge, the manganiferous metachert is exposed intermittently for 330 feet. The thickness of the ore ranges between 4 and 8 feet. The bed appears to be offset by faults in places. One or more smaller manga- niferous beds may lie parallel to the main bed. xVnother exposure of manganiferous metachert is about 250 feet down the slope to the east. Other exposures occur at intervals up to a quarter of a mile southeast, where the shaft exposes a manganiferous metachert cut b}'' quartz veins. Little manganese, however, is present at this place. AYhere the road crosses the ridge, 1,700 feet west of the place men- tioned as the "main workings," manganiferous rocks are exposed at intervals wnthin an area about 100 feet long and 30 feet wide. Two or more beds probably are present here, unless one has been repeated by faulting. At one place a block of ore about 6 feet thick, is exposed, and another bed about 30 feet north is exposed for a width of 2 or 3 feet. The ore beds and enclosing schist at the main workings strike N. 45° -70° W., and dip 40° to 50° NE. At the shaft to the east the strike is N. 60° W., and the dip close to vertical. The manganese ore consists of psilomelane and pyrolusite, contain- ing red iron oxide stains and larger or smaller patches of the quartzose material of the metachert. Some of the ore appears to be rather high grade, and should run 45 percent manganese. Other ore is much lower in grade, however, and the one cut that was completed across the ore bed at the time of the visit revealed material which was mostly quartz, with manganese oxides scattered through it. The bed here probably does not average more than 10 percent manganese. At the outcrop about midway between the main workings and the shaft is parth' oxidized pink rhodonite, which is probably the main primary mineral of the Nigger Hill deposit. No. 7. Shasta Copper Mine (Pit River Consolidated). (By R. R. Morse, July 29, 1918.) Manganese ore has been mined on claims belonging to the Shasta Copper Company, situated on the south side of the Pit River directly opposite the Noble Electric Steel plant at Heroult. This plant is served by the privately owned Sacramento Valley and Eastern Railroad, connecting the mining district of Bully Hill with the main line of the Southern Pacific at Pit Station, 6 miles west of Heroult. The Shasta Copper Companv's property consists of 38 mining claims comprising the Si sec. 36, T. 34 N., R. 4 W., and the W-JNEi sec. 1, T. 33 N., R. 4 W. The manganese ore shipped to the smelter was mined from workings near the center of the N|SE^ see. 36. Outcrops of similar ore occur at other localities on the claims, notably at a point near the center of the Wi sec. 1. The claims are said to have been located for the purpose of develop- ing supposed copper deposits underlying the prominent gossan of this region. Shallow cuts disclosed the presence of considerable manganese ore. Analyses of the gossan indicated that manganese occurred quite generally in the surface rock of the claims. In 1916 the claims were leased to the Noble Electric Steel Company. In 1916 and 1917 this company mined and removed about 1,000 tons of ore, using it in their nearby plant for 1 Geologic map of California, scale 1 :500,000, California Div. Mines, 1938. 268 MAXOAXESK I\ fAMKOKNIA [Bull. 152 the production of silico-mangauese alloy. The average manganese con- tent of this lot of ore is reported to have been about 27 percent. In the fall of 1917 operations at the mine ceased. The smelter offi- cials are said to have claimed that the ore could not successfully be used in the process because of electrode troubles produced by the ore. How- ever, the fact remains that silico-manganese was successfully manu- factured and disposed of from the 1,000-ton lot removed from the work- ings. The claims have not been operated since abandonment by the steel company. Assessment work by the owners has consisted in digging many shallow cuts exposing low-grade manganese ore at several points on the property. Several short tunnels were driven into the soft ore and country rock at the locality of the most promising exposures. These underground work- ings aggregate about 200 feet in length and are caved at several points. The ore removed from these workings and from an open cut above was wheeled in barrows to a 50-foot chute constructed of rough timbers, avail- able nearby. The chute conveyed the ore to a log bunker of 30- or 4()-ton capacity. From the bunker the ore was transported to bins on the south bank of the Pit River by mine cars over about 0.6 mile of track. From this point it was carried by aerial tram across the river to bins at the smelter. The manganese ore occurs within a mass of highly decomposed silice- ous porphyr3% exposed beneath heavy overburden by many cuts in a narrow area extending from near the center of sec. 36, T. 34 N., R. 4 W., southward to a point 0.3 mile west of the center of sec. 1 of the adjoining township. At many points in this area a hard gossan occurs at the sur- face, similar to the prominent "iron caps" commonly found in the vicin- ity of the iron-copper deposits. Manganese is also present in this hard gossan. The manganese-bearing porphyry occurs in the northwest corner of a broad, roughly rectangular-shaped area of shale and associated rocks of the Pit formation of Middle and Upper Triassic age, occupying the greater part of the adjacent township on the southeast, as mapped in the Redding folio of the U. S. Geological Survey.^ The prevailing strike in the vicinity is north and the dip in general is east though local variations are common. Progressively older belts of rocks crop out to the west. West of the manganese-bearing porphyry in places resting against it in abrupt contact, are outcrops of a dense briglit red jasper. This rock is cut by many complexly intersecting veinlets of quartz. It breaks into irregular sharp fragments in which a flinty texture and subconchoidal fracture are characteristic. Its color is due to a rather uniforml}^ distrib- uted fine red oxide of iron. Here and there slight stains of manganese oxide occur. Small crystals of pyrite and chalcopyrite occur scattered through the rock, as well as in the quartz veinlets. Secondary changes have developed a vitreous appearance in much of the rock, suggesting an early stage of recrystallization. This feature effectively masks any determinative features that might have previously existed. The jasper is strikingly similar to tlie red chert of the Franciscan group so commonly associated with manganese deposits in the Coast Ranges. The locality is, however, not far from the isolated area in sec. 36 mapped in the Redding folio -^ as "P>ully Hill rhyolite". The map of the =" U. S. Geol. Survey Geol. Atlas, Redding folio (no. 138) 190C. 3 Op. ctt. 1950] DESCRIPTION OF DEPOSITS 269 folio does not show the area of ore-bearing porphyry and the adjacent outcrops of jasper here discussed. The material mined as ore consists of an intimate mixture of black manganese oxides with kaolin, iron oxides, quartz, opal, and chalcedony, the decomposition products of the porphyry. It is soft and easily broken. Because of this character, and the close association of the ore minerals with the friable gangue, it is impossible in mining operations to improve the ore by selective sorting at the faces. On a small scale the distribution of manganese is irregular, but on a scale compatible with economic mining practice the ore is of a uniformly low grade. The lot of 1,000 tons of this ore, which was used at the smelter in the manufacture of alloy, is said to have averaged about 27 percent man- ganese. The impurities of this ore are shown in the following analysis : iron, 6.72 percent; phorphorus, 0.18 percent; silica, 34.04 percent; manganese, 19.77 percent; and gold, $1.65 per ton. The following sample was taken by selection of the material most heavily stained by oxides, chiefly from the black outer shells surrounding barren cores of 'Svaste." In places it carried thin crusts of alternating hard and soft oxide films, believed to represent psilomelane and pyro- lusite : manganese, 28.1 percent; ferric oxide, 6.2 percent; insoluble, 33.3 percent; available ox^^gen, 6.96 percent. The hard gossan occurring at several points on the claims has not been considered seriousl.v as ore. Several assays have, however, indicated that it commonly carries manganese. The amount of manganese in these samples varied from 10 to 15 percent. In places it is said to have assayed $1.25 or less per ton in gold, and several ounces of silver. This "iron cap ' ' is resistant to weathering. Its color varies from deep red to purple and maroon. It generally has a porous, leached appearance, and cavities are lined with oxides of iron, copper, manganese, and opaline silica. Very fine crj'stals of iron and copper sulphides are sprinkled throughout. Dull coatings of a powdery black manganese oxide are com- monly the latest linings of the cavities. Thin films of a harder steel blue oxide shoAving a shining or metallic luster sometimes alternate with the duller powder. At the main workings the ore has been exposed bj- stripping for a distance of about 150 feet. It is here between 55 and 60 feet in width, limited on the west by the red jasper in sharp -contact, and on the east by a gulch beyond which is the wide area of shale in the Pit formation. The longer dimension parallels the schistosity or shear planes which every- where traverse the ore-bearing porphyry. In this direction the ore expo- sures are limited only by overburden. Cuts here show streaks of ore clearly related to particularly crushed or sheared portions of the por- phyry, outward from which the dark oxides gradually fade over a dis- tance of several feet. In very few places is there an abrupt change from ore to barren bleached porphyry. Tn the lower-grade material the manganese oxides are present as stains and thin films along the multitude of shear planes and cross frac- tures cutting the porphyry. As the manganese content becomes higher, the dark oxide stains become broader ; films of pure oxides on shear planes are bordered by broad outward-fading zones of soft porphyry stained with the oxides. Where shearing is most pronounced the outcrops are nearlj^ uniformly stained and this ore may be thinly laminated. Very 270 MANGANESE IN CALIFORNIA [Bull. 152 commonly this lamination curves around harder parts of the rock so that in caving the ore, numerous oval or elongated pieces drop out. These oval pieces are invariabl.y found to possess heavily stained outer zones of varying thicknesses, surrounding circular cores of spongj'-, bleached, or iron-stained, kaolinized porphyry, altered almost beyond recognition. In fact the porphyry is everj^where so altered that only rarel}'' can satis- factory evidence be found of its initial character. The persistent tendency toward a concentric arrangement of these manganese-stained shells is noteworthy. The outline of the inner barren cores is always circular and the boundary between core and shell is remarkabl.y sharp. The material of the ore is generally soft crumbling clay, more or less stained with brown oxides of iron. Small angular grains of clear quartz may be noted by rubbing the clay between the fingers. Here and there the cores still retain evidence of the original porpli3'ritic nature of the rock, w'here clear anhedral quartz grains and lath-shaped and square patches of pure white kaolin occur scattered rather abun- dantly through a ground mass consisting of structureless siliceous clay, spotted with small patches of brown iron oxide. The porphyritic texture is also preserved in the outer shells where phenocrysts of quartz are preserved in their original position, but here these constitute the only original component of the rock not completely masked by alteration or by the heavy staining of the manganese. From the evidence thus obtained it is apparent that the rock enclos- ing the ore deposit was originally an acidic porphyry of medium to coarse texture containing rather abundant phenocrj-sts of quartz and feldspars in a groundmass cariying numerous smaller ferromagnesian minerals, but the texture of this groundmass is not now determinable. It is also apparent that kaolinization and shearing of the porphyrj' preceded the introduction of the manganese oxides, in part if not w'holly. Later altera- tions have resulted in the deposition of manganese oxides and opal in cavities in the original ore. Botryoidal crusts of thin alternating films of opal, dull-black powdery manganese oxide, and harder steel blue shining oxide, line the cavities at many places. By analogy with the geology of the region it seems probable that this rock is an alteration product of an intrusive similar to the alaskite por- phyry bodies associated with the copper deposits of the nearby Bully Hill, Iron ]\Iountain, and Little Backbone districts, described bj' Graton.'* In the earlier work similar rocks in the Bully Hill district w'cre termed "Bully Hill rhyolitc." The occurrence of the manganese ore does not, however, appear to parallel that of the copper ore described by Graton as replacing the alaskite. The presence of isolated quartz phenocrysts in the manganese ore has been described above. There is, however, no clear evidence of replace- ment in this ore. Tlic ore oxides appear to be present chiefly as heavy stains in the spongy mass of decomposed porphyrj^ and linings of cavities developed after the entrance of the ore. As pointed out above, the entrance of the ore solutions was apparently made possible, as in the copper deposits, by extensive shearing of the porph.yry. It appears probable that, with respect to manganese, the porphyry had become highly decomposed before the ore solutions were introduced. * Graton, L. C, The occurrence of copper in Shasta County, California: U. S. Geol. Survey Bull. 430, p. 81, 1910. 1950] DESCRIPTION OF DEPOSITS 2*71 Ore of the character exposed in the main workings of the claims is exposed for 150 feet, in widths of 55 to 60 feet. The longer dimension is limited only by overburden. Assuming these dimensions as limits, and that the ore continues in depth to the level of the gulch adjacent on the east, there should be about 25,000 tons thus available. This material could not be expected to run higher than 15 to 20 percent manganese. No. 8. Victor Mine. (By R. R. Morse, August 6, 1918.) Manga- nese ore has been reported from the property of the Victor Mining Com- pany, now operating the old Midas mine at Harrison Gulch, Shasta County, in T. 29 N., R. 10 W. It was discovered on the south slopes of Chauncelulu Mountain, at a point about 7 miles from the Midas mine. At this locality manganese oxides occur as irregular soft bunches and frac- ture fillings in a hard bluish quartzose rock believed to be metamorphosed chert. This rock is associated with quartz-mica schist, which is included in a broad area of serpentine and acidic intrusives, chief of which is quartz porphyry. No ore of commercial value was seen at the time of the visit, SISKIYOU COUNTY No. 1. Allen Mine. (By Frank S. Simons, August 1942.) This mine may be the same as Clear Creek, Barham, and Collier prospects. The Allen mine is in sec. 8, T. 44 N., R. 8 W., on the northeast side of Clear Creek, a tributary of McAdams Creek. It was located by Leslie Allen and Edward Snyder on July 21, 1941, and was subsequently pur- chased by Lewis and Reynolds. The prospect is 7 miles by road north of Fort Jones. James Allen worked the property in 1918 and shipped a small amount of high-grade ore. During the last few months a road has been built to the property and a small amount of development has been done with a bulldozer. An open cut 100 feet long exposes 20 feet of siliceous manganese oxide ore striking northeast and dipping 60° SE. About 5 feet of quartz- rhodonite ore is exposed along the hanging wall. Most of the ore consists of skeletons of manganese oxide surrounding cores of leached silica. The wall rocks are interbedded quartzite and quartz-mica schist. No ore crops out northeast of this cut. Fifty feet southwest of this cut another smaller cut reveals 10 feet of similar ore. The cut is caved, and the thickness of ore and the geologic relationships are not clear. About 20 tons of siliceous ore has been mined from this cut. This ore appears to be on the strike of the ore exposed in the cut to the northeast. Fifty feet west of the main cut a thin stringer of ore has been mined. A few tons of ore are piled on the stock pile, but no ore is exposed in the cut. Two hundred feet east of the main ore bed, siliceous manganese oxide ore crops out for 100 feet along the strike. No exploration work has been done here. The grade of the ore probably decreases with depth. The prospect is not regarded as promising because of the siliceous nature of the ore and the probability that the primary ore is largely rhodonite. According to Mr. Lewis, Vernon Farnum of Oakland, drilled a series of vertical holes along the projected strike of the main ore bed northeast of the main cut for half a mile, finding ore containing from 20 to 38 percent manganese in each hole. No other information on these drill holes was available, and their location is not known. No. 2. Baker Prospect. (By R. R. Morse, August 20, 1918.) A claim locally reputed to include outcrops of high-grade manganese ore 272 MANGANESE IN CALIFORNIA [Bull. 152 is situated near the summit of Rattlesnake IMountain, 12 miles by tlie Indian Creek road from Fort Jones. This locality is about 32 miles southwest of Yreka, in the southwest corner of T. 45 N., R. 9 W., on what is shown on the Siskiyou Forest Reserve maps as Scott Bar Moun- tain. The claim was located by Baker Brothers of Fort Jones. The country rock consists of evenly bedded dense black chert, separated by ])artings of slaty black shale. The chert is from 30 to 50 feet thick, and dips steeply. East of tlie cliert is an extensive area under- lain by Aveathered quartzite and quartz-mica schist, with scattered bands of dark phyllite. Fine-jrrained blue to jrray limestone occurs in two ledges only a few feet thick, 0.3 mile east of the chert, within the area of quartzite. Thin laj-ers of graphitic mica schist which occur have been mistaken for ore by the claim owners. The rocks of this locality resemble the series exposed in the Wild- wood district (Trinity 81) , in the vicinity of the Lucky Bill (Trinity 58) and nearb}^ prospects. If the chert there exposed belongs to the Kennett formation, the chert on Scott Bar Mountain also may belong to this formation. No. 3. Barliam Prospect. (Modified slightly from original description in California Min. Bur. Bull. 76, p. 81, 1918.) Dr. W. W. Barham of Yreka reports he has made locations on a body of somewhat siliceous manganese oxides in sec. 9 or 16, T. 44 N., R. 8 W., southwest of Yreka. The claim is near a wagon road, 11 miles from the railroad. The manganese-bearing material is 10 feet wide. The property is unde- veloped. No. 4. Brown Prospect. (By Frank S. Simons, August 2, 1942.) Bert Brown of Cecilville is reported to have a manganese prospect in sec. 30, T. 39 N., R. 10 W., in the first gulch northeast of Shadow Creek, a tributary of the east fork of the south fork of the Salmon River. The prospect is 6 miles by road and half a mile by trail northeast of Cecil- ville, 22 miles from Sa-wyers Bar, and 77 miles from Yreka, the nearest railroad point. The writer examined this gulch for 1 mile above the Salmon River. The only manganese-bearing rock seen was a small amount of quartz sericite schist carrying thin films of manganese oxide. The prospect was not found. Mr. Brown was not in the area at the time of the writer's visit, and none of the people contacted knew Avhere the prospect was. Many recrystallized white chert fragments were found in the gulch, but no manganese was associated with them. The prospect, to judge from the float found, is probably of little consequence, and the primary ore mineral is likely to be rhodonite. No. 5. Callahan District. (By Frank S. Simons, August 20, 1942.) Inquiry was made at Callahan, in sec. 20, T. 40 N., R. 8 W., regarding manganese prospects in the vicinity. A few pounds of very siliceous ore were said to have come from an abandoned gold prospect on the crest of Scott Mountain near the road from Callahan to Trinity Center, presumably in sec. 32, T. 40 N., R. 7 W. No ore Avas in sight when Tiie prospect was abandoned, and it was not visited in this investigation. This deposit is the only occurrence of manganese reported in the district. No. 6. Chaparral Hill Prospect. (By Frank S. Simons, August 1942.) The Chaparral Hill deposit is in sec. 9, T. 43 N., R. 9 W., on the top of Chaparral Hill near the northwest end. It is 2 miles by road and 1.5 miles by tractor road southwest of Fort Jones. The property was 1950] DESCRIPTION OF DEPOSITS 273 leased by the West Coast Metals, Ltd., of which the members are Toy L. Young, H. C. Wadell, James C. Rodger, and Charles M. Wolfe. The company is said to have shipped one car of ore which failed to meet government specifications of low-grade B ore (35 percent manganese). The lease has been terminated and the property is idle. A remnant of a more extensive bed of manganiferous chert overlies quartz-mica schist. The chert is 25 feet thick at the thickest part, and averages 10 feet in thickness. It crops out over an area 40 feet long by 30 feet wide. The ore is a siliceous oxide material, disseminated in reerystallized chert. The oxide also occurs as films along fractures in the chert. No pri- mary ore was found. A small amount of ore contains 40 percent manga- nese, but the average grade of the deposit is 20 to 25 percent. No. 7. Collier Prospect. (By R. R. Morse, August 1918.) The Collier prospect is near the Allen deposit (Siskiyou 1) , in sec. 8, T. 44 N., R. 8 W., 16 miles west of Yreka. It is owned by B. K. Collier. The deposit is low in grade, consisting of films of manganese oxide. The average manganese content is less than 10 percent. No. 8. Crawford Prospect. (By Frank S. Simons, August 11, 1942.) The Crawford prospect is in see. 28, T. 46 N., R. 12 W., on the west side of Gricler Creek about 1,000 feet above the creek. It is 1.5 miles by trail from the China Creek-Marble Mountain road, 8 miles from Seiad Valley, and 51 miles from Yreka, the nearest railroad point. The prospect is idle at present. It was located by Cyrus Crawford of Seiad Valley. At the edge of a landslide bench on the steep west wall of Grider Creek canyon are numerous large fragments of manganiferous chert. This belt of chert can be traced for half a mile along the strike, which is north. At the south end is a small amount of banded rhodonite-quartz rock, apparently in place. The remainder of the ore is purplish chert, metamorphosed to quartzite. The associated rocks are diorite, gabbro, hornblendite, and serpentine. An assay of the purple manganiferous chert gave 8 percent manga- nese. There is perhaps 100 tons of this material in sight, and no more can be predicted as all the rock is in landslides. No development work has been done. No. 9. Davis Prospect. (Modified slightly from original descrip- tion in California Min. Bur. Bull. 76, p. 81, 1918.) Reeves Davis of Happy Camp has a manganese prospect 8 miles above Happy Camp, and 1 mile east of Indian Creek in T. 17 N., R. 7 E. The ore body is said to be 7 feet thick. No development has been done. No. 10. Dozier Prospect. (Modified slightly from original descrip- tion in California Min. Bur. Bull. 76, p. 81, 1918.) M. Dozier of Los Angeles owns a deposit in sec. 15, T. 46 N., R. 6 W., 6 miles southwest of Klamathon between Montague and Hornbrook. The deposit is said to be a large body of siliceous manganese oxide containing 30 percent silica and 37 percent manganese. In May 1918 the Noble Electric Steel Com- pany of San Francisco was reported to have an option on this deposit, but no ore was shipped. Siliceous manganese oxides are reported in quan- tity on the ridge north of Greenview and southeast of Oro Fino, in sees. 20 and 21 ( ?), T. 43N., R. 9 W. 274 MANGANESE IN CALIFORNIA [Bllll. 152 No. 11. Etna District. (By Frank S. Simons, Aii feet of llie surface of the ground. The grade of the ore is estimated to average about 20 percent manganese, but in places is as high as 35 percent. No. 10. Big Boy Deposit. (By Cliarles R. Warren, August 26, 1941.) The Big Bov deposit is situateil at an altitude of 2,000 feet in the SE^SWi sec. 17, T. 3 S ., R. 6 E., half a mile from a road and 6 miles from Alder Point, the nearest rail point. It is on land owned by Arthur Cross- man. No development has been done. Tlie ore body lies in green and white chert, which strikes N. 75° "W., and dips 65° to 85° N. The deposit runs diagonall.y up the hill for 75 feet. The average width is 4 feet. The ore consists of stains on chert and the grade is under 3 percent manganese. No. 11. Big Buck. (By Ivan F. Wilson, July 22. 1941.) The Big Buck claim is in the SE^ sec. 4, T. 1 S., R. 8 E., on the Long Gulch trail, half a mile north of the Forest Glen-Hayfork road, and 1,600 feet west of The Manganese claim (Trinity 90). It was located by p]d\vin Lowry on Februar.y 24, 1941. The nearest railroad is 70 miles distant. This claim contains an outcrop of manganese chert 20 feet wide and 30 feet long. The chert strikes N. 40° ^Y., and dips 15° SW. A trench 3 feet deep has been opened around the ore body to the northwest and northeast. This cut exposes chertj" shale, and also some greenstone on the northwest. Serpentine crops out in a gully on the southeast. No rock is exposed on the southwest. The manganese is in the form of incompletely oxidized bementite and perhaps neotocite. The bementite is partly coarsely crystalline, in tabular crystals up to half an inch in diameter. These were determined microscopically by F. S. Simons. The crystals have a thin coating of black oxide. The average grade of the manganese chert is 10 percent or less. Perhaps 500 tons of this type of ore is present. No. 12. Big Horn No. 1 Prospect. (By Parker D. Trask, April 8, 1942.) The Big Horn No. 1 is located at an altitude of about 3.000 feet on the William P. White Estate. 0.3 mile from a road and 10 miles from Alder Point in the SE^ sec. 9, T. 4 S.. R. 6 E. It is under lease to Rae F. Helmke. The deposit lies 0.7 mile southwest of Schoolhouse No. 1. It is on the north side of a steep slope in which the bedrock consists of sheared chert. The deposit is 1 foot wide and is exposed for a distance of 5 feet on the side of a cliff. The ore consists of manganiferous chert and rhodo- ehrosite. The grade is estimated to be less than 10 percent manganese. No. 13. Big Horn No. 2 Prospect . (From files of U. S. Geological Survey, 1942.) The Big Horn No. 2 prosi)ect lies near the Big Horn No. 1 prospect (Trinity 12) in sec. 9, T. 4 S., R. 6 E. The ore body is said to be 4 feet thick but relatively low in grade. The primary mineral is reported to be rhodoehrosite. No. 14. Big Rock Claim. (Bv Ivan F. Wilson. July 25. 1941.) The Big Rock claim is in the SAV] sec. 12. T. 3 N., R. 6 E., on the Eltapom trail. It is reached by proceeding north from Hyampom Post Office for 2.5 miles, and turning west 0.3 mile to the Mosher's Ranch. The prospect is then reached by trail along the west side of a ridge half a mile west of Mosher's Ranch, The nearest railroad is 90 miles away. The claim was 1950] DESCRIPTION OF DEPOSITS 307 located by William Rowland and Eniil V. Lehmann, Jr., on August 29, 1940. The ore consists of thin films of manganese oxide or chert. About 6 cuts have been dug into the hill slope, but no manganese was seen except in the form of stains. An assay ran 0.81 percent manganese. The chert is surrounded by greenstone and serpentine. No. 15. Black Bird Claim. (By W. G. Pierce, August 8, 1941.) The Black Bird claim is near the town of Ruth, in the N^ ( ?) sec. 4, T. 2 S., R. 7 E. This deposit was located by J. N. Hutchens on August 3, 1941. The deposit was not visited because of the low grade of the samples from it that were seen. They consisted of manganese stains on chert similar to the other deposits visited in the general vicinity (Trinitv 16 and 25). No. 16. Black Hawk Claim. (By W. G. Pierce, August 8, 1941.) The Black Hawk claim is in NWi sec. 3, T. 2 S., R. 7 E., 1 mile northwest of Ruth, and 1 mile from the road. It was located bj'' J. N. Hutchens on August 1, 1941. The deposit consists of manganese stains in chert. No commercial ore was seen. No. 17. Black Hawk Claim. (By Ivan F. Wilson, July 29, 1941.) The Black Hawk claim is 600 feet north of the Jewett claim, in the NW^ sec. 32, T. 29 N., R. 11 W. It is described in the report on the Jewett claim (Trinity 48). The claim was located July 1, 1941, by George W. Silvester. The property contains a pit in greenstone 6 by 2 feet, and 2 feet deep. The greenstone contains a few manganese oxide films along fractures. The grade is probably less than 1 percent manganese. No. 18. Black Oak Mine. (By Parker D. Trask and A. F. Shride, November 22, 1942.) The Black Oak mine is located at an altitude of 4,000 feet in the NW^ sec. 5, T. 3 S., R. 6 E., on a claim located by A. C. Grossman and T. K. Tj^ree in 1940 or early in 1941. During World War I, 25 tons was piled on a dump near the mine, but no ore was actually shipped. The deposit at that time was in the name of Pat and Mary Cox. It is located on a ranch road, about 10 miles from Alder Point, the near- est rail point. The deposit lies in a belt of thin-bedded red chert which extends in a northwesterly direction for more than 700 feet. The ore body itself is 3 to 5 feet wide and dips vertically. When visited in 1941, the ore body could be traced for 40 feet. The ore consists of siliceous oxide, which seemingly becomes poorer in grade with depth. No rhodochrosite or bementite was seen. The deposit was worked during the spring of 1942 by A. Z. Grossman (brother of A. C. Grossman), and after much sorting, a car was shipped, but the grade failed to meet Metals Reserve Gompany specifications. A large cut was made along the ore body in the summer of 1942 and all the ore mined out. The mine was then abandoned. No. 19. Black Rock Claim. (Bv Ivan F. Wilson, Julv 25, 1941.) The Black Rock claim is in the SWi sec. 12, T. 3 N., R. 6 E. It is 200 yards south of the Big Rock claim ( Trinity 14). The claim was located August 12, 1940, by Lawrence Leckrone. An area of manganese ore about 12 feet in diameter lies in a body of white chert. The ore occurs as black coatings on light-colored chert, and as compact masses of black oxide. Some patches of pink rhodonite were seen, and this is evidently the primary mineral from which the oxide was derived. Some of the oxide ore is fairly high grade. An assay of one sample averaged 46.35 percent manganese. 308 MANGANESE IN CALIFORNIA [Bull. 152 EXPLANATION y^ Fault ' showing dip y/ Geologic contoct "^d^ Open pit -;^- Underground workings Jfc JfS Mongonese ore eiposed ore is primary, consisting of tiousmonnite, rtiodoclirosite and hydrous silicotes. Aver, grade 50% Mn Thin bedded chert mostly pale buff or greenish near ore beds, with thin shole portings. Red chert common away from ore beds. Sondstone 'Jfq'-| Greenstone ^ ^ - ^^1 porphyritic. si porphyritic, sheared and altered - clearly intrusive. MAX 0. CRITTENDEN, JR AUGUST 1944 Figure 9. Geologic and topographic map of the Blue Jay mine, Trinity County, California. 1950] DESCRIPTION OF DEPOSITS 309 The white chert which encloses the ore strikes N. 40° E., and dips 55° N. The chert is completely surrounded by serpentine, and is regarded as a roof pendant in serpentine. About 50 tons of ore are reasonably expectable from the present exposures. Although i^art of this runs 45 percent manganese, the average is probably closer to 15 percent. The possibilities are slight for any great reserves. No. 20. Blue Jay Mme (Blue Bird Claim). (By Parker D. Trask and Fred D. Trauger, November 1, 1942.) The Blue Jay mine is one of the best deposits of manganese discovered in California during World War II. It was found by J. M. McKnight and F. A. Stockel in May 1941. They took out two claims, one the Blue Jay under the names of J. M. McKnight and A. M. McKnight; and the other, the Blue Bird, under the name of W. A. Stockel. The claims are situated in NW^ sec. 17, T. 26 N., R. 12 W., at an altitude of 4,200 feet, on the west side of the divide between the Mad and Eel Rivers. The deposits were leased in the summer of 1941 to I. D. Budd and associates, who started to build a road to the deposits but soon abandoned their efforts, presumably for lack of funds. The deposits were taken over by James I. Scott Company in the spring of 1942. A road 4 miles in length was built from the end of the road on the south fork of the Mad River, and the first ore was shipped early in the sunmier of 1942. By November 30, 1942, 1,500 tons of ore running between 50 and 55 percent manganese, and 8 to 10 percent silica had been shipped to the Metals Reserve Company. The ore is shipped 80 miles by truck to Alton; one round trip per day per truck. The deposits were opened up on the south end, and as of November 1, 1942, had been worked for a distance of some 200 feet, and to a maximum depth of 100 feet in two ore bodies, each averaging 3 to 4 feet in thickness. They lie in thin-bedded white chert which strikes northwest and dips 50° NE. In August 1941 a plane table map of the deposits was made by Charles R. Warren and Frederick D. Trauger of the IT. S. Geological Survey (fig. 9) . This map was subsequently brought up to date by Frank S. Simons in 1942 and by Max D. Crittenden in 1944, after mining opera- tions had begun. When the deposits were first discovered, the ore body could be traced for 300 feet more or less continuously along the strike, and one exposure of ore to the northwest in the projection of the strike was found at a distance of 150 feet beyond the last outcrop of the main ore bod3^ The mining operations have shown that the ore bodies extend for at least 150 feet farther to the southeast than was apparent before they were developed. The southeast limit of the deposits has not been determined, for the ore body still continues at the southeastern end. At the place where the ore is being mined at present the ore bodies are continuous and are not materially offset by faults, but to the northwest small faults displace the ore, and at the northwest end 200 feet beyond the present workings the ore body is faulted off and its continuation has not been found, except for the one outcrop 150 feet farther to the north- west. The upper ore body can be traced for only 200 feet, whereas the lower one is exposed more or less continuously for 400 feet. The ore consists of high-grade oxides at the surface. These contain from 50 to 60 percent manganese. They give way at depth to a mixture of hausmannite, carbonate, and bementite, and in places carry a little native copper. This copper is found mainly in calcite veins which cut most of the other minerals. Chemicals analyses of the primary ore give 310 MANGANESE IX CALIFORNIA [Bull. 152 from 50 to 55 percent manganese, 6 to 10 percent silica, and 3 to 9 percent carbon dioxide. The proportion of the primary minerals varies consider- ably, but in places the ore seems to contain hausmannite. The hausmannite is dark reddish-brown and is very fine-grained, but in thin section shows a triangular and diamond shaped pattern. X-ray patterns give typical hausmannite lines. The red color of the hausmannite induced the oper- ators to throw away considerable ore in the earl}^ period of mining, and one dump was found to have an average content of 40 percent man- ganese. Blue Jay Mine. (By Max D. Crittenden, Jr., August 1944.) The Blue Jay mine was opiated by James I. Scott to October 1943, and up to that time had produced 2,900 tons averaging 50 percent manganese. It was then taken over by J. P. Warren who till August 1944 had pro- duced 1,745 tons averaging 51 percent manganese, 1.35 percent iron, and 12 percent silica. The outcrop of the ore beds has been stripped by means of a bulldozer to a depth of 25 feet at the south end, and 35 feet at the north end. The ore was mined selectively. Earlier development consisted of three principal adits begun on the eastern slope of the ridge. These were abandoned partly because of the difficulty of following and locating the faulted segments of the ore beds. Manganese ore occurs at the Blue Jay mine in two beds, about 15 feet apart, enclosed in thin-bedded chert of the Franciscan group. On the eastern slope of the ridge the average strike of the beds is N. 55° W., and the dip is 60° -75° NE. This general trend continues west to about the crest of the ridge where a fault striking N. 50° E., and dipping 55° SE. displaces the beds slightly, and produces a change in attitude. West of the fault, the beds strike N. 20°-30° W., and dip 20°-30° NE. Only one fault is exposed, but others probably exist as is indicated by irregulari- ties and apparent discontinuities in the ore. The segments of the ore beds west of the fault are not exposed. How- ever, the No. 2 bed was worked for a distance of 125 feet from the fault in an open trench later filled. This segment appears to be the same bed that was exposed in the northwest edge of the pit in August 1944 (fig. 9) . The greenstone exposed in the pit is a relatively thin body which was apparently injected approximately along the contact of the chert and sandstone, exposed in the north edge of the pit. Northwest of the greenstone, the chert merges along the strike with sandstone. The chert has been bleached white in places along the greenstone contact. The ore from the open pit is largely primary, as surface oxidation usually forms only a coating of black oxides 1 inch to 2 inches thick. The primary ore is mostly reddish-brown hausmannite, cut by veinlets of rhodochrosite, or hydrous silicates. Quartz veins were observed, which carry some chalcoeite, and which have formed inesite by reaction with the other manganese minerals. Secondary copper minerals include native copper, cuprite, and malachite. No. 21. Blue Lizard Prospect. (From files of U. S. Geological Survey, 1918.) The Blue Lizard prospect is on the White Ranch, 0.3 mile from the road, 10 miles east of Alder Point, near the Big Horn deposits (Trinity 32 and 13) in sec. 9, T. 4 S., R. 6 E. The prospect is leased to Rae F. Ilelmke of Alder Point, but has produced no ore. The ore body is exposed for a quarter of a mile. It varies in width but seem- ingly is of low grade. Representative assays give manganese, 30 percent ; silica, 25 percent ; and a relatively high iron content. 1950] DESCRIPTION OF DEPOSITS 311 No. 22. Bonanza Claims. (By A. F. Shride and S. C. Creasey, August 1941.) The Bonanza claims are in the S^- sec. 3, T. 27 N., R. 12 W. Two claims, the Bonanza and Bonanza No. 1, were located on July 4, 1941, by F. A. Stockel and J. M. McKnight. The claims extend 1,'500 feet to the north, and 600 feet to the east. They have a common boundary. The Bonanza claim is west of the Bonanza No. 1. The claims are 3.5 miles by poor trail from the nearest road, and about 600 feet higher than the road. The last 2,500 feet of trail rises 400 feet. The trail takes off from the road to the Three Forks of the Mad River, which i.s approxi- mately 14 miles by road southeast of the town of Ruth. The Hoaglin Quadrangle covers all the above mentioned roads and reference points. Before the ore can be shipped, 3.5 miles of road must be built. The last 2,500 feet would be hard to construct. Part of this distance would either go up the creek bottom or be blasted from solid rock. The first 3 miles could be made with bulldozers. Numerous creek crossings would be necessary along any proposed route. From Three Forks it is 80 miles to Carlotta. The general strike in the area is northwest and the dip is northeast with varying degrees of steepness, ranging from about 30° to nearly vertical. The rocks are of the Franciscan group. The sandstone is a medium-grained rock containing quartz, feldspar, chert, shale, and ser- pentine ( ? ) fragments. It lies on the southwest side of the chert and greenstone and dips under them toward the northeast at an angle of 50°. The greenstone occurs within the chert as irregular potato-shaped patches with the long axes parallel to the strike of the chert. The distribution of the greenstone suggests that it parallels the strike of the chert. Three patches of greenstone are present. Thej^ may represent the same igneous body, which could be either a flow or shallow sill. The original composi- tion and texture of the rock has been destroyed during the alteration to a greenstone. However, the hardness and color of the rock suggest it was at least as basic as an andesite, if not a basalt. Three separate landslides are recognizable on the two claims. The rubble is mostlj^ chert with some ore scattered throughout the lowest slide. The lowest slide overlies the sandstone, which shows that the slide moved in a southwesterly direction from the chert member, partly covering the sandstone-chert contact and coming to rest in the creek bottom. Subse- quently the creek has cut through the slide leaving it exposed on both sides of the stream. Manganese ore is found in two exposures on the Bonanza No. 1 claim as well as in irregular blocks in the landslides and along the creek bottom. All the ore seen on both claims is oxide. The western bedrock exposure of the ore is the best on the claims. It is 70 feet long and at least 12 feet thick in the thickest part. The footwall is unexposed along the entire length. The bed lies conformably in the chert. Three grades of ore were recognized in this bed. The bulk of the ore was estimated to contain around 30 percent manganese. For a distance of 40 feet along the foot- wall was a band of high-grade ore which contains about 40 percent manganese. The remainder of the ore is highly siliceous and contains less than 30 percent manganese. The ore body 200 feet east of the main manganese outcrop is 3.5 feet thick and is conformable with the chert. It contains about 30 percent manganese. No. 23. Briggs Deposits. (By Charles R. Warren, August 25, ]941.) The Briggs deposits are at an altitude of 3,000 feet, 1 mile north 312 MANGANESE IN CALIFORNIA [Bull. 152 of Zenia in the W^ sec. 10, T. 3 S., R. 6 E. The deposits are half a mile trom a road and 15 miles from Alder Point, the nearest rail point. They are npon patented land owned by Dean Briggs. Development consists of a pit, which presumably dates from the last war. The deposit consists of manganese stains on red chert, and is of little value. No. 24. Broken Hammer Prospect. (From files of U. S. Geologi- cal Survey, 1942.) The Broken Hammer prospect is on the White Ranch 0.3 mile from the road, 10 miles east of Alder Point, in sec. 10, T. 4 S., R. U E. It is leased to Rae F. Ilelmke of Alder Point. The ore zone is said to be 7 feet thick, but is low grade and siliceous. No. 25. Brown Dog Claim. (By W. G. Pierce, August 8, 1941.) The Brown Dog claim is in the SW-^ sec. 34, T. 1 S., R. 7 E., on the north bide of the Mad River 3 miles northwest of Ruth. The claim was located by J. N. Ilutchens in April 1941, The deposit consists of manganiferous chert striking N. 30° W., and dipping 35° NE. A representative sample contained 5.28 percent manganese. In one place the chert seemingly con- tains a little carbonate and bementite, but not sufficient to make the deposit promising, as the deposit passes into chert within 2 feet. Nos. 26 and 27. Bucking Camp Deposits No. 1 and No. 2. (By Parker D. Trask and Frank S. Simons, April 7, 1942.) The Bucking Camp deposits are located on the Rohrbaugh Ranch in sec. 32, T. 3 S., R. 6 E., at an altitude of 2,500 feet. Deposit No. 1 is in the NW:^ and No. 2 in the NE^ of the section. No. 1 is 1 mile from the Alder Point road and No. 2 is 1.5 miles from the road. The distance to Alder Point is 8 miles. Bucking Camp No. 2 was not visited but the ore body is said to be low in grade and small in size. In the Bucking Camp No. 1 deposit the ore bed is exposed at intervals for 125 feet and has an average width of 2 feet. Presumably it is continuous throughout the entire interval, but without additional excavation this inference cannot be verified. The ore bed is in red chert and strikes N. 75° W., and dips 40° NE. The grade is variable. At the surface the ore consists of oxide but at depth it probably gives way to rhodochrosite, though none was seen. The average grade is esti- mated to be 25 percent manganese. The thinness of the ore body, the comparatively low grade and the uncertainty of linear extent combine to make this deposit unattractive. Nos. 28 and 29. Carr and Carrie Claims. (By Parker D. Trask, June 1941.) The Carr and Carrie claims and the adjoining Louella claim (Trinity 57) are located in the SW^ sec. 30, T. 31 N., R. 12 W., about 8 miles west of Hay Fork on the south side of the Tule Creek road to Indian Valley. The deposits are 0.2 mile from the road and 58 miles from the railroad at Redding. The three claims were located in the fall of 1940 by W. B. Carr, E. E. McFadden, and Thomas M. Porter. They were leased in the fall of 1940 to William Vance and associates. At the time the deposits were visited in June 1941, the claims had not been developed. The manganese is in a belt of thin-bedded purplish manganiferous chert 400 feet wide and at least 800 feet in length. The strike is northeast and the dip is nearly vertical. The chert is cut off by greenstone on the two sides and seemingly is a roof pendant in a basic plutonic rock. The manganese content is nowhere more than 20 percent, and the general average is probably under 10 percent. The manganese is concentrated in three places; two at the northeast end, 300 feet apart across the strike, and the other 600 feet to the south across a ravine. The northeast 1950] DESCRIPTION OF DEPOSITS 313 deposit is on the Louella claim, the southeast one is on the Carr claim, and the southwest one is the Carrie claim. The Carrie deposit is lower grade than the others. It does not have much ore containing over 5 percent manganese, and it lies adjacent to greenstone. No. 30. Cedar Springs Claim. (By Parker D. Trask and A. F. Shride, June 1941.) The Cedar Springs claim is 0.3 mile southeast of the Black Susan claim (Trinity 6) in the NWi sec. 31, T. 1 N., R. 8 E. It was located by J. W. Patton of Hayford. It lies in thin-bedded chert in the projection of the chert in the Arrowhead and Susan claim (Trinity 6), but is separated from that body of chert by greenstone. The ore is found in segregations in the chert, but the quantity is even smaller than in the Arowhead and Susan claims. The grade is of the order of 15 per- cent manganese. No. 31. Claim 23. (By Parker D. Trask, July 1941.) A pit was found about 50 feet north of the road to Limedyke, 150 feet due east of the section marker betAveen sees. 29 and 30, T. 1 N., R. 8 E., about 13 miles west of Hayfork and 80 miles from Redding. Another pit was found 150 feet to the east. The pits are 3 feet deep, and expose manganiferous chert in thin-bedded red chert. The grade of ore is less than 10 percent manganese. This claim has been designated Claim 23. No claim notice was found. The location of this deposit is uncertain, because the position of the section markers made by the Forest Service in their timber cruising operations does not correspond with those given on the Hoaglin topo- graphic map made by the IT. S. Geological Survey. Nos. 32 and 33. Coldwater No. 1 and No. 2 Deposits. (By Parker D. Trask, April 7, 1942.) The Coldwater No. 1 and No. 2 deposits are in the NEi sec. 5, T. 4 S., R. 6 E., at an altitude of about 3,000 feet. They are on deeded land in the William White Estate. Coldwater No. 1 is 50 yards below the road, and No. 2 about a quarter of a mile below the road. Both are 10 miles from Alder Point, the nearest rail point. About 50 tons was mined in 1942 from each deposit by Rae F. Helmke of Alder Point. The ore consists of blocks of high-grade manganese oxide lying in land- slide debris. Mining is by bulldozing and hand sorting. No ore has yet been found in place. The debris associated with the ore consists prin- cipally of chert. The source of the deposits higher on the mountain has not yet been found. Much of the ore is of high grade, and the average is estimated to be over 45 percent manganese. The estimation of reserves is hazardous because of the uncertainty as to the distribution of ore in the landslide debris. About 25 tons is estimated to be in sight at No. 1, and 10 tons at No. 2. No. 34. Corner No. 1 and No. 2 Prospects. (From files of U. S. Geological Survey, 1942.) The Corner No. 1 and No. 2 prospects are located upon the White Ranch half a mile from the road, 10 miles east of Alder Point in sec. 5, T. 4 S., R. 6 E. They are leased to Rae P. Helmke of Alder Point. The soil is covered with float of manganese oxide similar to the occurrence of manganese in the Coldwater deposits (Trinity 32 and 33) which are nearby in the same section. No. 35. Coyote Claim. (By Charles R. Warren, August 25, 1941.) The Coyote mining claim is in the SW^ sec. 13, T. 3 S., R. 6 E., at an altitude of 3,800 feet on the road 0.9 mile south of Zenia, and 8 miles from Alder Point, the nearest rail point. The claim was located May 26, 1941, by George A. Kniss and Lee Murphy. One pit now about 8 feet deep was dug during the last war. The deposits consist of manganese 314 MANGANESE IN CALIFORNIA [BuU. 152 stains iii a chert zone 5 feet wide. The strike is N. 35° W., and the dip 40° SW. The chert is reported to give way to sandstone below the present bottom of the pit. The grade of manganese is estimated to be less than 5 percent. No. 36. Dahrman Group. (By Parker 1). Trask, October 1942.) The Dahrman group of claims is the easternmost of the three groups of claims located hy John Hosier on North Yolla Bolly Mountain in sees. 32 and 33, T. 27 N., R. 10 W. For details see the description of the Bertha group of claims (Trinity 9). No. 37. DouUe-A Prospect. (By Frank S. Simons and Max D. Crittenden, Jr., July 16, 1942.) The Double-A prospect is in the center of sec. 16, T. 3 S., R. 8 B., on the west side of Horse Ridge near the head of the first large canj^on northwest of Barry Creek, a tributary of Mad River. It is about 1 mile northeast of the Mad River road and 74 miles from the railroad at Alton, the nearest rail point. At present the pros- pect is reached by 1 mile of trail. It was located by Robert Ilill and Ann Anderson on January 6, 1942, and is leased by the Victory Manganese Mines of Los Angeles. The manganese ore occurs in thin-bedded shaly red chert, striking north to N. 30° W., and dipping from 35° to 55° E, Two open cuts have been made. The south cut exposes a bed of ore ranging from a feather edge to 1 foot in thickness along a strike length of 8 feet. This exposure appears to be at the top of an ore lens. A small pod of ore occurs 4 feet stratigraphically below this lens. In the north cut, 30 feet from the south cut, an ore bed up to 2 feet in thickness is exposed. This bed appears to be olfset about 15 feet horizontally west of the south bed, and a fault is prob- ably the cause, although the bed may be sharply folded and not exposed. Twenty feet farther north a small cut has exposed a small amount of man- ganese ore which is probably a continuation of the bed in the north cut. The ore bed mav have a length of 100 feet, and a maximum thickness of 2 feet. The ore is mostly a reddish-black, very hard and heavj^ material similar to that at the Blue Jay mine (Trinity 20) farther south. It is thought to be a mixture of hausmannite and silica, and probably contains 40 percent manganese. A small amount of manganese carbonate replaces the hausmannite. Both these minerals are cut by later veins of rhodochro- site and quartz. A few green copper minerals, but no native copper, were seen. Very little black oxide ore was found, tlie primary minerals occur- ring within a few inches of the surface. Donhle-A Prospect. (By Max D. Crittenden, Jr., August 25, 1944.) The Double-A mine was leased in 1944 to J. B. Girdner who produced 87 long tons of ore averaging 39 percent manganese. A road has been built within 150 feet of the property and an ore bin and chutes have been installed. ^Manganese ore is exposed in three small pits on a steep hillside. It is enclosed by chert of the Franciscan group, striking gen- erally north, and dipping east, but the beds are so folded and faulted that it is uncertain whether all the exposures constitute a single lens. The ore is a banded mixture of the following minerals: (1) rhodo- chrosite, coarse-grained, commonly spherulitic, yellowish or buff -colored ; (2) hausmannite (?), reddish brown; (3) manganiferous chert, brown, semi-waxy; (4) bomentite, yellowish, scattered flecks and veinlets. The rhodochrosite in places is intimately mixed with manganiferous chert 1950] DESCRIPTION OF DEPOSITS 315 and quartz. The average grade of the ore is about 35 percent manganese, but a product averaging 40 percent can be obtained by careful sorting. A thin section of spheruiitie rhodochrosite shows radial aggregates 1 millimeter to 4 millimeters in diameter with some pale tan bementite in the interstices, and cut bj^ numerous small veins of granular quartz. The latest mineral is a bright yellow, felted or radiating fibrous serpentine-like mineral that has developed within and around the rhodo- chrosite spherulites, and along the grain boundaries of the quartz veins. It forms radiating needles and sheafs that extend out into the quartz or bementite that it replaces. This mineral is uniaxial negative, or biaxial negative, with a low 2V, showing strong cleavage, parallel extinction, and positive elongation. The birefringence is about 0.010, and the indices 1.70 to 1.71. No. 38. Dry Lake Prospect. (By Parker D. Trask, July 1941.) The Drv Lake claim is situated on the crest of Peak 3453, 2 miles south of Peanut in the SWi sec. 13, T. 30 N., R. 12 W. It was located in August 1940 by Clarence Patton of Peanut. Development consists of four trenches up to 10 feet in depth. No ore has been shipped. The deposit is 1 mile by trail from the road up Salt Creek, and 70 miles from the nearest railroad at Red Bluff. The claim was leased to Vance and Barnes in 1940, who carried on development work in the spring of 1941 but oper- ations were soon abandoned and no work has been done since. The ore consists of manganiferous iron oxide in more or less thin- bedded chert, which is surrounded by greenstone. The chert strikes east and dips nearly vertically. It is resistant to erosion and forms a prom- inent ridge. The ore zone is in two parts : One about 200 feet long, on the west end, and the other about 150 feet long on the east end. Between the two mineralized zones is a barren zone about 50 feet in length. The ore in the east deposit is estimated to contain less than 3 percent manganese, and in the west deposit about 5 percent. The ore is similar to that found at the Arrowhead claim (Trinity 6). It is dark brown and gives a dark brown streak. An assay from the west deposit gave 3.80 percent manga- nese. The iron content was not determined, but by analogy with similar deposits in the general region, it probably is of the order of 20 percent. The low manganese and high iron content cause this deposit to have little promise, even though the tonnage is high. The ore zone is completely surrounded hj greenstone, and it may give way to greenstone with depth. No. 39. Emma Group. (By Parker D."^Trask, October 1942.) The Emma group of claims is the westernmost of the group of claims located by John Hosier on North Yolla Bolly Mountain in sees. 32 and 33, T. 27 N., R. 10 W. For details see the description of the Bertha group (Trin- ity 9). No. 40. Foss Prospect. (By R. R. Morse, August 4, 1918.) Two claims belonging to Fred Foss of Knob Post Office, lie on a steep hillside north of Dubakella Creek, in sec. 16, T. 29 N., R. 11 W. They are leased to the Noble Electric Company. Several pits were excavated and the ore sampled. The material considered to be ore by the prospectors consists of a dense black chert heavily stained with manganese oxides. Near the sur- face, fragments of this chert exhibit outer rims of soft sooty manganese oxides mixed with a small amount of limonite. The proportion of this material to hard rock is very low. Fresh specimens of the rock from the bottoms of pits are very dark green to black, showing a dense flinty 316 MANGANESE IN CALIFORNIA [Bull. 152 Geology by W G Pierce Topography by F D Trauger August 1941 Ore io mixture of mongoniferous chert ^rhodochrootte or)d t^ousmonriite; the latter being more abundant near center of ore body Many veins of cotcite and mesite cut the ore near tite greenstone. Veinlets of pink rhodochrosite and resinous neotocite cut other minerals. Wollrocks ore chert , sandstone, and intrusive greenstone, of Franciscan group inesite veins sandstone chert grades into ^sondstone red, laminated, cherty shole and greenish chert -,-l,Cjo.sit. Placer County — see Pettigrew-Stafford, 170-171 Fox deposit, Alameda County — see Graves, 21 Grayson claim, Stanislaus County, 291 Great Expectation mine, Santa Clara County, 250-2r>l Green, Tom — Fable mine, Santa Clara, 249-250 Gregory and Moffitt — Manganese King mine, Tehama, 300 (Jrider Creek, Crawford prospects on, 273 (Jrier, Ben — Geronimo prospect, Inyo, 82 (Jriffin, Glenn C. — Lewis prospect, Napa, 158 Grizzly Canyon deposit. Lake County — see Vann Ranch, 98 (iroce mine. Riverside Countv, 178-179 ; see also Bray, 178, Parsons, 179, Arlington, 170-177 Gronzotto, Whitsun, White — Manganese Queen, Trinity, 323-330 Gross, Melville, deposit. Riverside — see Arlington, 170-177 Grummett Creek, Tip Top mine on, 298 deposit No. 2, Stanislaus County, 291 -Knox mine, Stanislaus County, 291 Ranch, Mezzero deposit, Stanislaus, 295 Gullman deposit, Colusa County, 50 Gunn, James Jr. — Little Falls deposit. Lake, 93 Guthrie deposit, Mendocino — see Spy Rock, 139-140 H Hadley, J. B. ; Wilson, Ivan F., and — rei>ort : Imperial County — Whedon, 79-80 Hale Creek mine. Trinity County, 310, 317-319, geologic map and section, 310 prospect, Mendocino County, 123 Hall deposit, Humboldt — see Charles Mountain, 04-05 Hamilton deposit, Stanislaus County, 291 , Richard — Apache claim, Kern, 84 Hammond prospect, Stanislaus County, 292 Hangover deposit, San Bernardino — See Big Reef, 188-191 Hannagan Ranch deposit. San Benito County, 180 Hans, Ora, prospect — Lake County, 94 Hansen, E. J. — Big Stony Creek mine, Glenn, 50 Happy Four deposit, Mendocino — see Earl W. Long, 129-130 Harder, E. C, report : Alameda County — Isler Mountain deposit, 21 Harms prospect, Mendocino County, 123-125, map, 124 Harp<>r prospect, Fresno County, 53-54 Harrington prospect, Calaveras County, 44, see also Murphys district, 43-44 Harris, Mrs. Antonia, Santa Clara County depo.sits : Black Eagle, 247, Black Horse, 247-248, Cedar Tree. 248, May Be, 254-255 Hart and Bear deposits. Trinity County, 319 Haskins and Kyte — Isom prospect, San I^uis Obispo, 231, 233 Haslet t, Wincliel, Woodward — Impassable Rock deposit, Mendocino, 120 Hastings deposit, Napa County, 158 Hauer and Hubbard — Consolidated claims, Mendocino, 110-118 INDEX 359 Hauselt prospect, Calaveras County, 44, see also Murphys district, 43-44 Hauser-Martin-Cheeseborough deposit. Riverside — see Langdon, 183-184 Haiismannite, in manganese deposits, 11-12 Hawkins mine, San Benito County, 186-187 Havden deposit, Sonoma County, 284 Hayfork Creek, deposits on : Cliff, 338, Weed, 340 Hazelton and Kennedy claim, Madera County, 103-104 Hearst mine, Alameda County, 21 Ranch, San Luis Obispo County deposits :-Marmolejo Creek, 230-231,-Red Rock, 231 Helbing, Harvey L. — Eagle's Head claim, Amador, 29 Helmke, Rae F., deposits: Humboldt County — Live Oak, 70, Prior No. 1, 71 ; Mendo- cino County— Linser, 127-128 ; Trinity County— Big Horn, 306, Blue Lizard, 310, Broken Hammer, 312, Coldwater, 313, Kekawaka, 320, Montgomery, 330, Schoolhouse, 334, Source, 335, Twisted Oak, 338-339 , and Crossman, A. — Shell View deposit, Trinity, 334-335 Heminway and Hurt — Nowlin mine, Mendocino, 133-134 Hendricks mine, San Benito County, 187 Henshaw Ranch, Mendocino County : Ocean View deposit, 134-135, Summer Camp deposit, 140-141 Henson, W. R. — Blue Monday claim, Napa, 156-157 Hermann claims, Lake County, 91 , Henry — Blue Monday claim, Napa, 156-157 , O. E. — Rattlesnake mine. Lake, 97 Herndon claim, Lake County, 91-92 Herrick prpspect. Lake County, 93 Heughes prospect, Mendocino County, 125 Hidden Treasure deposit, San Bernardino — see Monument King, 202-203 High Lead claim, Trinity County, 319 Light No. 1 claim, Siskiyou County, 274 Hill prospect, San Luis Obispo County, 231 and Anderson- — Trinitv Countv deposits : Armstrong, 302-304, Apple Flat, 302, Double-A, 3i4-315, White Oak. 341 Hinch, Robert S.— Salt Creek claims, Nos. 2 and 3, Trinity, 334 and Harriet— Salt Creek deposit, 333-334 Hinrichs property, Mendocino County, 125 Hixson, Walter — Caldwell mine, INIariposa, 106-108 Hobson deposit, San Luis Obispo County, 231 Hodges deposit. Imperial — see Turtle, 77 Hoelling, Henry W. — Jaybird claim. Trinity, 319-320 , Sarah T. — Last Chance claim, Trinity, 320 and Jules A. — Arrowhead and Black Susan claims. Trinity, 304 Hog Mountain prospect, Tuolumne County, 342-343 Holbrook and McGuire : Kelly mine, Alameda, 22, Winship Leases, Santa Clara, 264- 265 Hoist-Weeks prospect, Sonoma County, 284 Homestead deposit : Alameda County, 21, Mendocino Count.v — see Cleveland, 116 Hoopa Valley Indian Reservation, Sam Brown prospect on, 71-72 Hopper prospect, Mendocino County, 126 Horse Ridge, Double-A prospect on, 314 Horsetown formation, Ladd-Buckeye area, 215 Hospital Canyon deposit, Stanislaus — see Hamilton, 291 , Section 23 mine in, 297 Houselt deposit, Calaveras County, 44 Hoyt, A. H. — Summit deposit. Lake, 98 Hudson, F. S., report : Alameda County— see Davis, E. F., and, 15-16, 17-18, 19, 21-22, 25 Kern Countv — Culbert Bros., 84, Manganese Queen, 84, Midlothian, 84-85 Lake County— see Davis, E. F., and, 89, 93 Marin Countv — see Davis, E. F., and, 106 Mendocino County— see Davis, E. F., and, 112, 126, 127, 134-135 Monterey County — Evans, 153-154, Wayland Ranch, 154 Napa County — see Davis, E. F., and, 156, 157 Riverside County — Blackjack, 177-178, Social deposit, 180 ; see also Morse, R. R., and, 178-179 360 MANGANESE IN CALIFORNIA Hudson, F. S., repoi-t — Continued San Bernardino County— New Deal, 2():{-20r. San Diego County — Clark, 208, Engineer's Springs, 208, Machado, 209, Ruby. 20b, Turner, 211 San Luis Obispo Countv — Staneuohe, 237-238, see also Davis, E. F., and 233-234 Santa Barbara Countv — Byrne and O'Donnell, 241-242, La Laguna Ranoho. 242, ^lorey, 242 Santa Clara Coun(v— Faide. 240-250, see also Davis, E. F., and, 250-251, 253. 254. 25S Sonoma County — see Davis, E. F.. and, 283, 284 Stanislaus Countv — Sunbeam, 2!»7-208, see also Davis, E. F., and, 292, 293. 205 ;"and Morse, R. R., and, 290, 291 , and Alvey, G. H., report : Alameda County — Froitas, 21 San Luis Obispo County — Barneberg, 228-229, Black Mountain, 229, Bluebird, 229-230. Isom, 231, 233, Lanscioni, 2.34, Mar- quart, 234. Mavfiold. 234. Bhelan, 236, Ricioli, 237, Tobacco Creek. 239-240, Welch, 240-241 , and Morse, R. R., report : Imperial County — Lugo. 70-77 Inyo County — xVpril Fool, 80-81, Manganese Nos. 1 and 4, 83 San .loaquin County — Callahan, 221 , and Taliaferro, N. L.. report : Mendocino County — Dorn, 119, Hiurichs, 125, Scott, 137 Iluey i)rospect. Siskiyou County, 274-275 Hughes mine. Tuolumne County, .343-344, see also Heughes, 125 Hulls Creek. Red Cliff deposit on. 332 Humboldt County, deposits description. 03-73 Land and Development Co.- — Fort Seward mine, Humboldt, 66, 67-69 Hummingbird claim. Glenn County, 59 Humphreys, A. E. — Aho mine, Sonoma, 280-282 Gold Co. — Liberty mine, Stanislaus, 293 Hunt, Charles B., report : Inyo County— Black Dream. 81. War Baby, 83 , and Bowles. Edgar, report : San Bernardino Countv — Emma, 195, Owls Spring, 206 Hutchens, .L N.. Trinitv Countv deposits : Black Bird, .307. Black Hawk, 307. Brown Dog, 312 . and Moore, H. T.— Hale Creek deposit. Trinity, 316, 317-319 Hutchinson, Ed — Deaver deposit, Amador, 28 Impassable Rock deposit. Mendocino County, 126 Imperial County, deposits description, 73-80 Independent deposit. Mendocino — see Foster Mountain, 120-123 Ingram Canyon. Clear Creek deposit on, 290 deposit, Stanislaus County — see Tip Top, 298 Inyo County, def)osits description, 80-83 Iron Dyke deiwsit, Plumas County — see Braito, 172-173 Queen deposit, Plumas County, 175 Ironwood district. Riverside County — see Arlington, 176-180 (McCoy) Mountains, Arlington district in, 176-180 Isler Mountain deposit, Alameda County. 21 Isom prospect, San Luis Obispo County, 231, 233 Jackson, Alfred — Pine Ridge deposit, Santa Clara, 258-262 Jackson and Rochester — Desert Bloom deposit, Imperial, 76 Jacumba group, San Diego County, 208-209 Janes Creek prospect, Humboldt County, 09-70 Jan.son, Charles J. — Buckhf>ru dejmsit. Alameda. 10 Jasper pros|)ect, Tuolumne County, .344 Jaybird claim. Trinity County, 319-320 Jean, Mr. — Murphy i>rospect, Humboldt. 71 Jenkins, Olaf P., production data by, 9 INDEX 361 Jewett claim, Trinity County, 320 Johe Ranch mine, San Luis Obispo County, 232, 233, plan of lower level, 232 Johnson, A.W.V. — Mahoney mine, San Joaquin, 226-227 and Wright — Tip Top mine, Stanislaus, 298 Jones, A. H. — Murmac group, Santa Clara, 25G-257 deposits : Amador County, 30-31, Santa Clara County, 251-253, 218, 244, 245, map and sections, pi. 12, plan and sections. Parts I and II, pis. 13-14 Josephson prospect, Butte County, 36 Joses Ranch prospect, Calaveras County, 45 ; see also JMurphys district, 43-44 Julia deposit, Trinity County — see Vance, 339 Jumbo prospect, Alameda County, 21-22 Jumpoff claims, Mendocino County, 126 K Kappler prospect, Siskiyou County, 275 K. B. claims. Glenn County, 59-62 Keaster and Rose — Mendocino County deposits : Rose, 136, Wishbone, 148-149 Keegan, Gray, Miley — Inyo County deposits : April Fool, 80-81, Manganese Nos. 1 and 4, 83 Keeney, F. W. — Mendocino County deposits : Bevins-Busch, 112, Liberty, 127 Kekawaka deposit. Trinity County, 320 Keller Bros, prospect, Santa Clara County, 253 , Charles and Vesta — Elephant Hill prospect, Glenn, 58-59 , Matt — ^Santa Clara County deposits : Antonia, 246, Cedar Tree, 248, Cotton- wood, 248 mine, Santa Clara County, 253 Kelley, A. M., prospect, Santa Clara County, 253-254 Lake prospect, Siskiyou County, 275 prospect, Santa Clara County, 254 Kellogg mine, Calaveras County, 45-46, see also Murphys district, 43-44 Kelly mine, Alameda County, 22 Kelm prosi>ect, Mariposa County, 109-110 Kennedy, J. J.^ — Newsom prospect, Santa Clara, 257-258 Kenzie deposit, Riverside County — see Arlington, 176-177 Keough deposit, Kern County — see O. K., 85 Kern County, deposits description, 84-87 Kester prospect, San Luis Obispo County, 233-234 Kiel, Herman — Paddy Faulkner claim. Riverside, 185 King deposit, Siskiyou — see National Defense, 277 , W. W. — Big Indian claim, Kern, 84 Kingbird gold mine, Yuba County — see Bean, 347 Knapp and Hillstead — Bertha deposits. Trinity, 305-306 Knight prospect, Mendocino County, 126-127 Kniss and Murphy — Trinity County deposits : Bear Ridge, 304, Covote, 313-314, Look- out, 321 Knox, Mr., Stanislaus — see Grummett-Kno.x mine, 291 Knoxville group, Glenn County, 58 Knutte deposit, Marin County, 105 Kootz, Kimball, Ellis — Black Beauty deijosits, San Bernardino, 191 Kroger, Fred — Arlington district, Riverside County, 176-180 Krohn prospect, Madera County, 104 Kuppinger & Pinkham — Nigger Hill deposit, Shasta, 266-267 L La Bree claim, Lake County, 93 , Jack— M. & G. claim. Lake, 93-94 Frentz deposit, Los Angeles — see Red Feather, 102-103 Laguna Rancho deposit, Santa Barbara County, 242 Ladd-Buckeye area : geology, 211-221, map and sections, pi. 4 and Black Wonder areas : index map showing, 210, ore bodies, table showing range in size, 218 fault, Ladd-Buckeye area, 224 mine, San Joaquin County, 223-226, 211, 213, 216, 217, 218, 219, 221, 245; geo- logic and topographic map of area, pi. 6, geologic map of levels, pi. 8, plan and geologic sections, pi. 7, vertical projection, pi. 9 362 MANGANESE IN CALIFORNIA Lagunitas Development Co., Mnilliiinl Uiiiich deposit, Marin, lOfi Lake County, deposits dpscrii)tion, S7-1(M) , Mack C— Sau Joaquin County deposits : Fabian, 222, Ladd, 223-226 View deposit, Plumas — sec Valley View, llCt Ijampley deposits, Trinity County, :}20 Lanipson and Schultz — Archamheau prospert, Sonoma, 282 Lanudon dei)osit. Riverside County, 1S8-1S4 Lankin deposit. San Bernardino — see Black Kaven, 19.3-194 Lanscioni prosjx'ct. San Luis Obispo County, 234 Lasbl)ou};b and Foley properties, Butte County, 36 Lasky, Pierce, Warren, Trask, report : Ladd Mine. San Joaciuin County, 223-226 Last Chance claim, Mendocino County — see I'^arl W. Ix)ng, 129-130 , Trinity County, 320 Hope claim, Trinity County, 320 Latham, Ray — Jewett claim. Trinity. 320 Lavagnino prospect, Calaveras County, 4(5, see also Murphys district, 4.3-44 Lavic Mountain deposit, San Bernardino — see Lee Yim, 195-200 Lawson, A. C, report : Fort Baker mine, Marin County, 105 ; Red Rock deposit, Contra Costa County, 50 Leach Lake Mountain claims, Mendocino County, 127 Leaning Tree No. 2 claim, Humboldt County, 70 Leap prospects, Mendocino County, 127 Leckrone, Lawrence — Black Rock claim. Trinity, 307-309 Lee deposit, Mendocino County- — see Bevins-Busch, 112 Lee ( ?) deposit. Placer — see Yankee Jims, 172 Yim deposit, San Bernardino County. 195-200 Leidy & Harris — Manganese Queen, Kern County, 84 Lelaiid, W. L.— Manganese Peak, Tehama County, 300-301 Leona deposit, Mendocino County, 127 Levensaler and Speir deposit, Glenn County, 62 Lewis prospect : Napa County, 158, Siskiyou County, 275 Foundation Corp.- — Bluebird mine, San Luis Obispo, 229-230 Ranch deposit, San Benito County, 188 and Reynolds, Siskivou County deposits : Allen, 271, Fort Jones, 274, Oro Fino Nos. 1 and 2, 277-278 Liberty claim : Mendocino County, 127, Napa County, 158, (prospect) Plumas County, 175, (mine) Stanislaus County, 293, 211, 212, 217, 218, 219, geologic and topographic map, pi. 19, plan and vertical projec- tion, pi. 20 TJghthill prospect, Siskiyou County, 275-276 Lillie mine, Inyo County, 82-83 Lincoln deposit. Imperial — see Pilot Knob, 77 liine Gulch deposit, Mendocino — see Ijeacb Lake Mountain, 127 Linser mine, Mendocino County, 127-128 Little Deer prospects Nos. 1 and 2, Trinity County, 320-321 Falls deposit. Lake County, 93 Live Oak deposit, Humboldt County, 70 Livermore deposit, Alameda County, 22 Llewellyn iron i)roperty, lios Angeles — see Black I>ros., 100-101 Lloyd prospect. Placer County, 170 Lockwood prospect, Tehama County, 299 Jjogan mine : San Bernardino County, 200-201, (claim) Tehama County, 299-300 Lombardi prospect, Napa County, 1.58 Lone Indian deposit, Mendocino — see Consolidated, 116-118 Tree claim, Mendocino County, 128-129 fault, Ladd-Buckeye area, 212, 214, 216 Mining Co., Cummings mine, San Joaquin County, 221-222 Lonesome Pine deposit. Trinity — see Bertha, 305-306 Long, Earl W. prospect, Mendocino County, 129-130 F. J., prospect, Mendocino County, 130 Gulch, Jaybird claim in, 319 Loofbourrow, C. E. — Mangatop prospect, Nevada, 164 Look Out claim, Stanislaus County, 293 Lookout deposits. Trinity County, 321 Lopez prospect, Santa Clara County, 254 INDEX 363 Los Angeles County, deiiosits description, 100-103 Lost Donkey deposit. Imperial — see Lugo, 76-77 Mine deposit. Trinity County, 321-322 Soldier deposit, Plumas County, 175 Louderback, George D., research by, 15 Louella group. Trinity County, 322 Lovett, M. J. — Midlothian mine, Kern, 84-85 Lowry. Edwin — Big Buck deposit, Trinity, 306 Lubanko prospect, Amador County, 31 Lucky Bill prospect, Trinity County, 322 Boy deposit, Mendocino — see Foster Mountain, 120-123 Star claim, Trinity County, 322-323 Strike deposit, Sonoma — see Archambeau, 282 Sunday mine. Trinity County, 323 Sunday and Billy Sunday claims. Trinity County, 323 Ludwig, Dorothy — Fortner Ranch prospect. Calaveras, 42-43 Lugo claims, Imperial County, 76-77 M Mabery and Brown deposit, Riverside — see Langdon, 183-184 MacDonald prospect, Imperial County, 77 Machado prospect, San Diego County, 200 Mad River, deposits on : Apple Flat, 302, Armstrong. 302-303. Brown Dog. 312, Hale Creek, 317, Hart and Bear, 319, Lost Mine, 321, Lucky Sunday and Billy Sunday, 323, Mary Lue, 330, North Fork, 331 Madera County, deposits description, 103-105 Madrid prosi>ect, Tuolumne County, 344 Magnesia Camp deposit, Stanislaus County, 293-295 Mahoney mine, San Joaquin County, 226-227, 211, geologic map, pi. 10 Mailliard Ranch prospect, Marin County, 106 Maker, George I. — American claims. Trinity, 302 Mammoth mine, Santa Clara County, 254 Mammoth Lakes deposit, Madera — see Agnew Meadows, 103 M. & G. claim. Lake County, 93-94 Man Ridge mine, Alameda County, 23 Manga-Chrome Co., Nevada County, 162-164 Manganese Claims : Imperial County (name unknown), 73 Inyo County— Nos. 1 and 4, 83, Nos. 1-6— see Death Valley, 81-82 Lake County — No. 1 — see Hemdon, 91-92 ; No. 2 — see La Bree, 93 Mono County — Nos. 1-4 — see Taylor, 152-153 San Bernardino County — Nos. 1-10 — see Lee Yim, 195-200 Siskiyou County — Nos. 1-4, 276 Stanislaus County— No. 14, 289-300 Trinity County (claim), 338, No. 23, 313 Manganese Cliff, San Bernardino — see Black Prince, 192-193 Extension, Riverside — see Giant Chief, 183 King, San Bernardino — see Black Prince, 192-193, and Monument King, 202-203 , Tehama County, 300 Mine, Calaveras — see Harrington, 44 ; see also Murphys district, 43-44 Peak, Tehama County, 300-301 prospecting, aids to, 11-14 Queen mine : Kern County, 84, Trinity County, 323-330, geologic and topo- graphic map, 324 Ridge, Napa — see Moore Creek, 158-159 Mangatop prospect, Nevada County, 164 Manilla deposit, Calavera.s — see Kellogg, 45-46 ; see also Murphys district, 43-44 Manion, A. P. — Beal-McClellan property. Riverside, 180-182 Manning, C. W. — Burns prospect, Humboldt, 63-64 Maple Springs deposit, Trinity — see White, 340 Marin County, deposits description, 105-106 Mariposa County, deposits description, 106-112 Marmolejo Creek, Hearst Ranch deposits on, 230 364 MANGANESE IN CALIFORNIA Marquart prospect. San Luis Obispo County, 234 Martell, Dr. — Bean prospect, Yuba, 347 mine, Amador County, 31 Martin, John T. — Airola mine, Calaveras, 38^0 and Murphy claim, Huml)oldt County, 71 Martinez Gold Mine Co., El Dorado County, 52 Maiy Ix)u deposit, Stanislaus County, 295 Lue claim. Trinity County, 330 Mason, Mr. — Braito mine, Plumas, 172-173 Ma.ssen, J. II. — Black Stone deposit, San Bernardiuo, 1!)4 Mateos Ranch deposit, Santa Clara County, 254 Mature Cons deposit, Inyo — see Lillie, 82-83 Maxwell and Walker — Big Little Bear claim, Calaveras, 40 May Be deposit, Santa Clara County, 254-2.55 Mayfield prospect, San Luis Obispo County, 234 Mayland Mining Co., Siskiyou County, 276-277 Mazza prospect, Marin County, 106 McCarty prospect, Nevada County, 164 McClendon prospect, Mendocino County, 130 McCombs and Hill — Cobb Alountain prospect, Lake, 89 McCoy deposit, Santa Clara County, 255 McCoy (Ironwood) Mountains, Arlington deposits in. 176-180 McCreary Ranch deposit, San Benito County, 188 McDermott Ranch, Pine Ridge mine on, 2.58-262 McDonald property, Sonoma County, 284 and Clark, Alameda County deposits : Dewhirst, 19-20, Newman, 25 McDowell deposit, San Bernardino — see Dawson, 194-195 McEachern, J. L. — White-O-Ranch deposit, Sonoma, 285-286 McKnight, J. M. and A. M.— Blue Jay mine, Trinity, 308, 309-310 associates — Hart and Bear Deposits, Trinity, 319 Stockel, F. A. — Lucky Sunday and Billy Sunday claims. Trinity, 323 et al. — Red Knoll deposit, Humboldt, 71 McLaughlin claims, Mendocino County, 131 McLean and Clark, Pine Flat deposit, Sonoma, 285 McMillan, Calvin— Queen Bee claim, Santa Clara, 262-263 McMillan, W. J., and Williamson, A. E. — Sunset prospect, Plumas, 176 McMurty prospect, Fresno County, 54 McPherson prospect, Santa Clara County, 255 , Mrs. Venita — Taylor property, Mono, 152-153 Mead prospect. Lake County, 94 Mebam deposit, Nevada County, 164-165 Mebold and Camiu deposit, Mariposa — see Strickland, 110-111 Mello prospect, San Luis Obispo County, 234-235 Melvin deposit. Riverside — see Parsons, 179 ; see also Arlington, 176-177 Mendenhall mine, Alameda County, 24 , O. W. — Corral Hollow mine, Alameda, 19 Mendocino County, deposits description, 112-150 Merced County, deposits description, 1.50 Merchant deposit, Alameda — see Camp Nine, 17 Estate — Ala Mountain mine, Santa Clara, 240 , J. W. — Corral Hollow mine, Alameda, 19 Mexican deposits, Santa Clara County, 255 Mezzero deposit, Stanislaus County, 295 Miami prospect. Mono County, 151 Michaels, Roman, Weeks deposit, Mendocino County, 132, see also Brereton, 113-114 Middle Creek deposit. Lake — see Vann Ranch, 98 Midlothian mine, Kern County, 84-85 Midway deposit, Nevada — see Ryan, 166-167 Mill Creek, Lighthill pro.spect on, 275 Miller prospect, Santa Clara County, 255 INDEX 365 Millett, Thomas O. and Jess L. — Leaning Tree claim, Humboldt, 70 Mine Development Co. — Chocolate Drop claims, Imperial, 74-76 Miner, A. B.^ — Arlington district, Riverside County, 176-180 Mineral Materials Co. — Stewart mine, San Bernardino, 206-207 Mitchell deposit, Stani-slaus County — see Hamilton, 291 Mocettini prospect. El Dorado County, 52-53 Mono County, deposits description, 150-153 Mono prospect No. 7, Mono County, 151-152 Monterey County, deposits description, 153-154 Montezuma Improvement Co., Mendocino County, 132 Montgomery deposit, Trinity County, 330 , T. J. — Manganese Claim, Trinity, 338 Monument King deposit, San Bernardino County, 202-203 Moody deposit, Trinity County, 330 Moore Creek prospect, Napa County, 158-159 M-Q deposit, Mariposa — see Sunrise, 111-112 Moran Bros. Mine, Stanislaus County, 294, 295-296, 217, geologic map, 294 Morey prospect, Santa Barbara County, 242 Morgan Hill prospect, Santa Clara County, 256 Morrison prospects, Mendocino County, 132-133 , Foster, Brereton — Star claim, Mendocino, 140 and Brereton — Two Trees prospect, Mendocino, 145-146 Morro Bay prospect, San Luis Obispo County, 235 Morse, R. R., report : Imperial County — see Hudson, F. S., and, 76 Inyo County—see Hudson, F. S., and, 80-81, 83 Riverside County— Bray, 178, Red Rock, 179-180 San Bernardino County — Black Mountain, 191-192, Black Raven, 193- 194, Lee Yim, 196-200, Northrup, 205, Reinerth, 206 San Joaquin County — -see Hudson, F. S., and, 221 Shasta County— Shasta Copper Co., 267-271, Victor, 271 Siskiyou County- Baker, 271-272, Collier, 273 Stanislaus County — Briukerhoffer, 287 Tehama County— Cavaleri, 298-299 Trinity County — Foss, 315, 317, Murphy-Bramlette, 331, Svlvester- Wilson, 337-338, Weed, 340 , and Hudson, F. S., report : Riverside County — Groce, 178-179 Stanislaus County — Clear Creek, 290, Grummett, 291 Mosier, John — Trinity County deposits : Bertha, 305-306, Dahrman, 314, Emma, 315 Moulton mine, San Bernardino County, 203 Mt. Bishop deposit, San Luis Obispo — see O'Connor Ranch, 235-236 Hamilton prospect : Alameda County, 24, Santa Clara County, 256 Hough deposit, Plumas — see Crystal Lake, 173-175 Sanhedrin deposit, Mendocino — see Consolidated, 116-118, and Impassable Rock, 126 Mountaineer deposit. Riverside County, 184-185 Moy deposit, Stanislaus — see Moran Bros., 294, 295-296 Moyle, George — Mono County deposits : Champion, 151, Taylor, 152-153 Mud Creek, Ware deposit on, 339 Mulkern, Hugh A. — Strickland prospect, Mariposa, 110-111 Mullings and Chambers — Steep Hollow claims, Butte, 37 Munson group. Trinity County, 331 Murmac group, Santa Clara County, 256-257, 218 ; geologic map and sections, pi. 15 Murphy-Bramlette prospect. Trinity (see — Bramlette), 331 Murphy, Mrs Dave — A. B.C. claim, Humboldt, 63 , Glen — Nigger Hill deposit, Shasta, 266-267 prospect, Humboldt County, 71 Murphys district, Calaveras County, 43-47 Muscio prospect, San Luis Obispo County, 235 Mustang deposit, Plumas — see Valley View, 176 Myers prospect. Lake County, 94 Myton and Kloppenberg deposit, Plumas — see Crystal Lake, 173-175 366 MANGANESE IN CALIFORNIA N Napa County, deposits description, 154-161 Nasland, Harry, and associates — Emma deposit, San Bernardino, 195 National Defense claims, Siskiyou County, 277 Neafus Peak deposit. Trinity — see Moody, IVM , White deposits on, .'540 Neally, Tom — Wonder mine, Tuolumne County, 346-347 Neason Ridge, Snowy claim on, 86 Ned deposit. Trinity — see Vance, 339 Neidefifer, I>ee — Murmac group, Santa Clara, 256-257 Nelson, J. M., report : Hutte Countj' — Bear Canyon, 35 Plumas County — Cannon, 173, Dickie Bird, 175, Iron Queen, 175, Lost Soldier, 175, Sunset, 176, Valley View, 176 Nelson Lease, Alameda County, 24-25 Neotocite, in manganese deposits, 13 Nevada County, deposits description, 161-168 Newberry Mountains, Black Raven group in, 193 New Deal mine, San Bernardino County, 203-205 New Year deposit, Mendocino — see Brereton, 113-114 Newhall, E. P. — Great Expectation mine, Santa Clara, 250-251 Newman property, Alameda County, 25 Newport (Newport Black Eagle) deposit. Riverside — see Beal-McClellan, 180-182 Newsom prospect, Santa Clara County, 257-258 Nichelini prospect, Napa County, 159 Nichols, G. T. — Social mine, Riverside, 180 Nicol deposit, Shasta County, 266 Nigger Heaven deposit, Nevada — see Ryan, 166-167 Hill deposit, Shasta County, 266-267 Noble Electric Steel Co. deposits : Alameda County — Livermore, 22, Man Ridge, 23 ; Mendocino County — Heughes, 125, Leona, 127, Shell Rock, 137, Spy Rock, 139-140; Plumas County— Braito, 172-173; San Luis Obispo County — Welch, 240-241 ; Santa Clara County — Pennsylvania, 258 ; Trinity County — Foss, 315, 317 Noble Lease, Santa Clara — see Pennsylvania, 258 and Johnston — Lucky Bill Prospect, Trinity, 322 Noblitt, Lelon — Box Canyon prospect, Riverside, 182 Norbeck, H. P. ; Pierce, W. G., Trask, P. D., and — report : San Joaquin County — Cummings, 221-222 North Fork deposit. Trinity County, 331-332 Northrup prospect, San Bernardino County, 205 Nowlin mine, Mendocino County, 133-134 O O'Brien and Miller — Overlook claim. Lake, 94-95 Ocean View deposit, Mendocino County, 134-135 O'Connell prospect, Sonoma County, 284-285 O'Connor Ranch mine, San Luis Obispo County, 235-236 O'Day, M. M. — Pennsylvania deposit, Santa Clara, 258 Ogler, Lee — Section 14 mine, Alameda, 26 O. K. claim, Kern County, 85 O'Kelly prospect, Tulare County, 342 Old Country deposit, Mendocino — see Brereton, 113-114 Old Dough claim. Lake County, 94 Orchard deposit, San Bernardino County, 205-206 Oro Fino Nos. 1 and 2 prospects, Siskiyou County, 277-278 Valley, manganese in, 277 Orr claim, Inyo County, 83 Overacker, Horace T. — Black Jack mine, Alameda, 16 — Jumbo prospect, Alameda, 21-22 Overlook claim. Lake County, 94-95 INDEX 367 Owl Head (Hole) deposit, San Bernardino County — see New Deal, 203-205 Lake area, Inyo County, Tertiary section, SI Mountains, New Deal mine in, 203 Owls Spring prospect, San Bernardino County, 200 Owlshead Mountains, Owls Spring prospect in, 200 , Emma deposit in, 10") Oyster Rock deposit. Lake — see Cohh Mountain, SO P Paddy Faulkner claim, Riverside County, 185 Page, James E., Mendocino County deposits : Dorn, 110, Young, 149-150 Paine Bros, claim, Nevada County, 105 Palen Mountain deposit. Riverside County, 1S5 Palen Mountains, Doran deposit in, 1S2 Palo Verde deposit. Imperial — see Lugo, 70-77 Panamint Mountains, Connard Bros, deposit in, 81 Panoche, Ladd-Buckeye area, 215 Park group, Stanislaus County, 290 Parsons deposit, Riverside County, 179 ; see also Arlington, 170-177 Patterson and Western Railroad — Magnesia Camp deposit, Stanislaus, 293, 295 deposit, Santa Clai-a — see Murmac, 250 Pattner, John — Billy Goat prospect, Santa Clara, 240 Patton, Charlotte M. and J. W. — Gool claims. Trinity, 317 , Clarence — Dry Lake prospect, Trinity, 315 , Clarence A. and Willis H. — Snow Camp claims, Trinity, 335 , J. W., Ti-inity County deposits : Cedar Springs, 313, Whiteman, 340 , Ralph A.— Gool No. 3 claim. Trinity, 317 Paymaster district, Whedon deposit, Imperial, 79-80 Peachtree Creek, Mary Lou deposit on, 295 Pedro prospect, Tuolumne County, 344-345 Penitencia Creek deposit, Santa Clara — see San Jose, 203 Pennsylvania deposit, Santa Clara County, 258 Penrose prospect : Mono County, 152, Plumas County, 175 Pereni prospect, Amador County, 31-32 Pescia prospect, Calaveras County, 40 ; see also Murphys district, 43-44 Petaluma-Point Reyes prospect, Marin County, 100 Pettigrew-Stafford lease, Placer County, 170-171 Peyton et al. lease, Amador — see Pereni, 31-32 Peyton prospect, Amador County, 32-33 Pfortner Ranch deposit, Calaveras — see Fortner, 42-43 Pharo deposit, Nevada County, 105 Phelan prospect, San Luis Obispo County, 230 Phillips mine. Lake County, 95-97 Pierce, C. S. — Sunshine deposit, Calaveras, 47 ; see also Murphys district, 43-44 , AV. G., report : San Joaquin Countv — Laskey (and others), 223-226; Trask, Parker D., and, 211-221 Stanislaus County — see Trask, Parker D., and, 291, 297 Trinity Countv— Black Bird, 307, Black Hawk, 307, Brown Dog, 312, Cliff, 338, Last Hope. 320, Lucky Star, 322-323, Mary Lue, 330, Munson, 331, North Fork, 331-332, Rattlesnake, 332, Reichert, 333, Salt Creek, 333-334 (see also Salt Creek Nos. 2 and 3, 334) , Two Sugar Pines, 339, AVoods, 341 ; see also Trask, Parker D., and, 316, 317 ; and Creasey (and others) , 324 , and Trask, Parker D., report : Stanislaus County — Liberty, 293 , and Trask, Parker D., and Norbeck, H. P., report : San Joaquin County — Cummings, 221-222 Pieta Creek deposit, Mendocino — see Pine Mountain, 135 Pilot Knob prospect. Imperial County, 77 Pine, E. B. — Surprise claim, Mariposa, 111-112 Flat deposit, Sonoma County, 285 Mountain prospects, Mendocino County, 135 Ridge mine, Santa Clara County, 258-202, geologic and topographic map, 260 Pinery Hill prospect, Siskiyou County, 278 Pinkham prospect. Riverside County, 185 368 MANGANESE IN CALIFORNIA Pit formation, Shasta County, 2G8, 269 Rivor Cons., Shasta — see Shasta Copper Co., 267-271 Pivotal fault, Ladd-Ruckeye area, 225 Placer County, deposits description, 168-172 Plattner, John — Mammoth mine, Santa Clara, 254 Plumas County, deposits description, 172-176 Plummer Peak prospect. Trinity County, 332 Pope, Z. E. — Gill Ranch prospect, Tulare, 342 Portal Ridge, Red Feather deposit on, 102 Porter Ranch deposit, Humboldt — see Fort Baker, 65, 67 Post Creek, Munson deposit on, 331 Potter Valley deposit, Mendocino — see Bevins-Busch, 112 Powell deposit, Butte — see Sunny Park, 38 Powers mine, Napa County, 160-161 Pre-Cambrian (?) gneiss, San Bernardino County, 192 metamorphics, Shasta County, 267 schist, Los Angeles County, 101, 102 Prefumo Canyon prospects, San Luis Obispo County, 236 Price prospect, Fresno County, 54-55 Prior No. 1 deposit, Humboldt County, 71 Production, California, 9-11 ; figures, 1867-1946, 10 Prospecting, aids to, 11-14 Pulse pro-spect, Santa Clara County, 262 Purple Sage group, Los Angeles County, 101-102 Q Quaternary sediments, Ladd-Buckeye area, 215 Queen Bee No. 1 claim, Santa Clara County, 262-263 Quintano deposit, San Luis Obispo — see Vollmer, 240 Quintano, Pedro — Kester prospect, San Luis Obispo, 233-234 R Rabe and Yim — Lee Yim deposit, San Bernardino, 195-200 Rainbow Ledge prospect, Lake County, 97 Rainy Day prospect, Trinity County, 332 Ramrod prospect, San Diego County, 209 Randel claim. Placer County, 171-172 Rathburu prospect, Colusa County, 50 Rattlesnake Creek, North — Gool claims on, 317 claim, Lake County, 97, Trinity County, 332 mine, Glenn County, 62-63 Mountain, Baker deposit on, 272 Ray, Jim — Spy Rock prospect, Mendocino, 139-140 Read, Gail G. — -American claims. Trinity, 302 Reay deposit, Alameda County, 25-26 Rechnagle, Richard — Black Ledge prospect, Nevada, 162 Red Cliff prosi>ect. Trinity County, 332-333 Cross deposit, San Bernardino — see Moulton, 203 Feather claim, Los Angeles County, 102-103 Knoll deposit, Humboldt County, 71 Mountain district, Doak No. 2 in, 249 Rock deposit. Contra Costa County, 50 , Riverside County, 179-180 ; see also Arlington, 176-177 Reed, George W.. Co. — Spy Rock prospect, Mendocino, 139-140 Rees, J. E. — Old Dough claim, Lake, 94 Reichert claim. Trinity County, 333 Reinerth deposit, San Bernardino County, 206 Reliance deposit. Trinity — see Bertha deposits, 305-306 Renfrew, Bonsack, Bolt — Acme Lode, Santa Clara, 245-246; Black Bolt claim, Stanis- laus, 286 Reynolds, T. E. — Lucky Bill prospect, Trinity, 322 Rhodes and Hurt prospect, Mendocino County, 135-136 Rhodochrosite, in manganese deposits, 12 deposit, Mendocino — see Impassable Rock, 126 Rhodonite claim, Siskiyou County, 278 INDEX 369 Rice, "Jake" — Woods property, Fresno, 56 Road claim, Trinity County, 333 Ricioli prospect, San Luis Obispo County, 237 Ricker, Spangler, report : Colusa County — GuUman, 50 Del Norte County — Siskiyou Fork Trail, 50, Stone, 51 El Dorado County— Buffalo Bill, 51 Inyo County — Geronimo, 82 Kern County — Apache, 84 Madera County — Thornberry, 105 Mendocino County — Graham, 123 Mono County — Penrose. 152 San Diego County— Del Monte, 208 San Luis Obispo County — Egenes, 230 Santa Clara County— Frankel, 250, ]\It. Hamilton, 256 Sonoma County — Dillon and Seefeldt, 283 Trinity County — Skaggs, 335 Tulare County— O'Kelly, 342 Riemert and Friend — Goat Camp claim. Shasta, 266 Ries and Jacobsen prospect, Napa County, 161 Riverside County, deposits description, 176-185 Roberts, E. C. — Pinery Hill prospect, Siskiyou, 278 Robie prospect, Mariposa County, 110 Robinson, Plant, Allen — Cry.stal Lake mine, Plumas, 173-175 Rockridge deposit, Glenn — see Big Stony Creek, 56 Rodonick deposit, Amador— see Germolis, 30 Rodriguez, Frank J. R. — Chaney lease, Alameda, 18-19 Rogers, A. F., report : San Jose deposit, Santa Clara County, 263 Rohrbaugh Ranch, Trinitv County deposits : Bucking Camp, 312, Rice Road No. 1, 333, Tan Oak, 338, Wagon, 339, Wood, 341, Wool Moun- tain, 341 Root deposit, Alameda County, 26 Rose deposit, Mendocino County, 136 Ranch deposit, Lake County, 97 prospect, Monterey County, 154 , Wm. — Good Enough claims, Nevada, 162 Round Mountain deposit, Mendocino — see Thomas. 142-145 Rowan, James H. — Dreamland mine. Sonoma, 283-284 Rowland and Lehmann Jr. — Big Rock claim, Trinity, 306-307 Rowlison prospect, Mendocino County, 136 Ruby prospect, San Diego County, 209 Ruhser and Hubberty deposit, Amador County, 33 Runge claim, Inyo County, 83 Runner and Brinkerhoffer deposit, Stanislaus County, 287 Rush Creek prospect, Plumas County, 175 Russ Co. — Fort Baker mine, Humboldt, 65, 67 Russell, Daniel — Cape Horn deposit, Placer, 168 Russell, Wallace A. — Kellogg mine, Calaveras, 45-46 ; see also Murphys district, 43-44 Rutherford, Mr. — Grummett-Knox mine, Stanislaus, 291 Ryan prospect, Nevada County, 166-167 Rymer, C. W. — Rush Creek prospect, Plumas, 175 S Sage Land Development Co. and Crocker National Bank — Usal deposits, Mendocino, 146-147 St. John, L. A., Calaveras County deposits : Harrington, 44, Zurcher, 47. See also Murphys district, 43-44 Sale and Butler — B. S. No. 1 deposit, Glenn, 57-58 Salinger prospect, Mendocino County, 137 Salt Creek claims. Trinity County, 333-334 Samovia, Ramon, San Benito County deposits : Fries Ranch, 186, Hendricks, 187 San Antonio Valley, Keller Bros, prospect in, 253 Benito County deposits description, 185-188 Bernardino County, deposits description, 188-208 Diego County, deposits description, 208-211 Francisco Bay, Red Rock deposit in, 50 370 MANGANESE IN CALIFORNIA San .T()!iuis ()i)ispo County, dejiosits description, 228-241 l*al)l(> fonnation, liadd-Iiuckeye area, 21") Santa liarhara County, deposits description, 241-242 Clara County, Klack Wonder area Kfology. 242-245 , deposits description, 24r)-2G5 Santo deposit, Nevada County, 1(57 Satterlee dejjosit, Trinity — see Vance, ^.W Sausalito I'oint dejxisit, Marin County, 10(5 Schellenjier, E. E., Riverside County deposits : Blackjack, 177-178, Red Rock, 179-180. See also Arlinjjton, 17(»-177 Schoettgen prospect, Tuolumne County, 84r> Schoolhouse claim. Trinity County, 384 Schroeder, Walt(>r J. — Triple Jump claim, Santa Clara, 263 Scott prospect : Madera Countv, 104, Mendocino County, 137, San Joaquin County, 227-228 , James I. Co.— Blue Jay mine. Trinity, 308, 309-310 Mountain, Callahan district deposits on, 272 River prospect, Siskiyou County, 279 and Winegar deposit, Alameda — see Man Ridge, 23 Seagrave deposit, Stanislaus — ^see Tip Top, 298 Searchlight deposit, Napa — see Blue Monday, 156-157 Searles deposit, Alameda County — see Man Ridge, 23 Section 13 deposit, San Joaquin — see Cummings, 221-222 Section 14 mine, Alameda County, 26 Section 23 mine, Stanislaus County, 297 Sehorn, A. W., et al. — Black Diamond mine, Glenn, 57 Seiad Creek prospect, Siskiyou County, 279 Serrano prospect, San Luis Obispo County, 237 Shamberger prospect, Butte County, 36-37 Shamrock No. 2 claim, Kern County, 85-86 Sharp prospect, Sonoma County, 285 Shasta Copper Co., Shasta County, 267-271 County, deposits description, 265-271 Shaw, James — Liberty prospect, Plumas, 175 and Matthews mine. Mendocino County, 137 Shell Rock deposits, Mendocino County, 137 View prospects Nos. 1 and 2 ; and No. 3, Trinitv Countv, 334-335 Shields, Robert— Lucky Star claim. Trinity, 322-323 , W. R.— High Lead claim. Trinity, 319 and Packwood — Thatcher Creek prospects, Mendocino, 141-142 Shride, A. F., and Creasey, S. C, report : Bonanza claims, Trinity Countv, 311 , Trask, Parker D., and— Trinity County, 304, 307, 313 Sierra Manganese, Plumas County, 175-176 Sihlis, R. — Four Point claim, Trinity, 317 Silvester, George W. — Black Hawk claim, Trinity, 307 Simons, Frank S., report : Alameda County— Chaney, 18-19, Man Ridge, 23, Nelson, 24, Sec- tion 14, 26 Humboldt County — Charles Mountain, 64-65, Leaning Tree, 70, Sam Brown, 71-72, Windbigler Nos. 1-2, 72-73 Mendocino County — Callizo, 115, Cooper, 118-119, Foster Mountain, 120-121, Hale, 123, Jumpoff, 126, Pine Mountain, 135, Shaw and Matthews, 1,37 San Joaquin County— Scott. 227-228 San Luis Obispo County— Hearst Kanch-Marmolejo Creek, 230-231, Hearst Ranch-Red Rock, 231, Johe Ranch, 233, Mello, 234-235, Morro Bay, 235, Prefumo, 236, Serrano, 237, Vollmer, 240 Santa Clara County— Newsom, 257-25S, I'ulse, 262, Winegar, 264, Winship leases, 264-265 ; see also Trask, Parker D., and 245- 246, 247-248, 253 r INDEX 371 Simons, Frank S., report — Continued Siskiyou County — Allen, 271, Brown, 272, Callahan distriet, 272, Chaparral Hill, 272-273, Crawford, 273, Etna, 274, Evcrill, 274, Fort Jones, 274, High Light, 274, Huey, 274-275, Kelley Lake, 275, Lighthill, 275-27(), Manganese Nos. 1, 2, 3, 4, 276, Mayland Mining Co., 276-277, National Defense, 277, Ore Fino, 277-278, Pinery Hill, 278, Rhodonite, 278, Scott River, 279, Seiad Creek, 279, Sylvester, 279 Sonoma County — Wright, 286 Stanislaus County— Gerber, 290-291 Trinity County — Moody, 330, Source, 335, Summit, 337; see also Trask, Parker D., and, 312, 320, 330, 334, 338-339, 341 ; and Creasey (and others) , 324, 336 , and Creasey, S. C, report : Trinity County — Spider, 335, 337 , and Crittenden, Max D. Jr., report : Humboldt County — Fort Baker, 65-67 Lake County— Dow, 89-90, Elliott, 90-91, Mead, 94, Vann Ranch, 98 Santa Clara County— Pine Ridge, 258-262 Trinity County— Apple Plat, 302, Armstrong, 303, Double-A, 314, White Oak, 341 , and Trask, Pai-ker D., report : Santa Clara County— Antonia, 246, Blackbird, 246-247, Black Eagle, 247, Black Wonder area, 242-245, Cedar Tree, 248, Cottonwood, 248, Jones, 251-253, May Be, 254-255, Mex- ican, 255. Murmac, 256-257, Queen Bee, 262-263, Triple Jump, 263 Stanislaus County— Black Bolt, 286, Black Mike, 286-287, Claim 14. 289-290, Look Out, 293, Mary Lou, 295, Park group, 296 , and Wilson, Ivan F., report : Alameda County — Dyer, 20 Mendocino County — Consolidated, 116-118, Impassable Rock, 126 Siskiyou County, deposits description, 271-280 Fork Trail deposit, Del Norte County, 50 Mountains, Wykoff deposit in, 280 Skaggs deposit, Trinity County, 335 Spring deposit, Mendocino County, 137 Skillen and Means deposit, Siskiyou — see Mayland, 276-277 Smith deposit, Nevada County, 167-168 , G. R.— Beal-McClellan property. Riverside, 180-182 , Jake, prospect — Stanislaus County, 292-293 , T. M.— Black Powder claim, Lake, 88-89 , Tom — McDonald property, Sonoma, 284 , V. R. — Sunset and Sunrise deposit, Fresno, 55 and DeVelter — Iron Queen deposit, Plumas, 175 Smithwick and Noble deposit, Butte County, 37 Smythe prospect. Lake County, 97 Snow Camp claims. Trinity County, 335 Snowy No. 1 claim, Kern County, 86-87 Snyder and Helmke — Hale Creek mine. Trinity, 316, 317-319 Soapstone claim, Calaveras County, 46-47 ; see also Murphys district, 43-44 Social mine. Riverside County, ISO ; see also Arlington, 176-177 Sonoma County, deposits description, 280-286 Source prospect. Trinity County, 335 South Thomas mine, Mendocino County, 137-139 Southern Pacific deposit. Imperial County, 77 Land Co. — Pettigrew-StafPord lease, Placer, 170-171 Spider claim, Trinity County, 335-337, geologic and topographic map, .336 Spring Hill Farm prospect. Lake County, 97-98 Spy Rock prospect, Mendocino County, 139-140 Stacy, Dr. J. T., Amador County deposits : Germolis, 30, Lubanko, 31, Stirnaman, 34-35 Stall and Butler — Hummingbird claim, Glenn, 59 372 MANGANESE IN CALIFORNIA Staneuche, Anton — Barneberp mine, San Luis Obispo, 228-229 mine, San liiiis Obispo County, 287-239 Ranch — Prefumo prospect, San Luis Obispo, 23G Stanisbius County, deposits rrison, 132-133, Rhodes and Hurt. 135-136, Star, 140, Summer Camp, 140-141, Two Trees, 145-146; see also Hudson, F. S. ; and, 119. 12.5, 137 Nevada County — Black Ledge, 162, ALnngatop, 164, Thompson, 168 Placer County — Emma, 168 INDEX 373 Taliaferro, N. L., report — Continued Plumas County — Braito. 172-173, Crystal Lake, 173-17."), Lil)orty, 175, West and Shaw, 176 Tuolumne County— Hos Mountain, 342-343, West, 345 Yuba County — Clemens, 348 , and Crook, Theo, report : Madera County — Hazelton and Kennedy, 103-104. Krohn, 104 , and Wilson, Ivan F., report : El Dorado County — Alderson, 51 Tan Oak deposit. Trinity County, 338 Tarry, George E. — Liberty claim, Napa, 158 Taylor property. Mono County, 152-153 , J. L., et al. — Leona deposit, Mendocino, 127 , L. G. and Hattie— Rattlesnake claim. Trinity, 332 , Mrs. Mildred— Black Mike claim. Stanislaus, 286-287 Ridge, Scott prospect on, 227 and Co., and Pitcher — Bartlett mine, Alameda, 15 Pitcher deposit, Alameda, 26 Teaford deposit, Madera^ — see Stewart and Nuss, 104-105 Tehama County, deposits description, 298-302 claims, Tehama County. 301-302 Terry, Mr. — F. J. Long pro.spect, Mendocino, 130 Tertiary age, Inyo County, 80-81 , Santa Barbara County, 242 sediments, San Bernardino County, 204 section. Owl Lake, 81 Tesla fault, Ladd-Buckeye area, 212, 214, 216 Tetzlaff, O. H. — Chocolate Drop claims. Imperial, 74-76 Texas Canyon, Purple Sage group in, 101 Thatcher Creek prospects, Mendocino County, 141-142 Thomas Bros. — Cave City claim, Calaveras, 41 ; prospect, Stanislaus County, 208 , Frederickson, Davis — Black Horse claim, Mono, 150-151 mine, Mendocino County, 142-145, geologic and topographic map, pi. 3 ; Nevada County, 168 ; San Luis Obispo County, 239 and Travers — South Thomas mine, 137-139 Thornberry deposit, Madera County, 105 Thorne, Lew, and Son — Phillips mine. Lake, 95-97 Thronson, Mary Lou — Stanislaus County deposits : Look Out, 293, Mary Lou No. 1. 295 Tilsley and Coplen, Placer County deposits : see Gold Hill, 169-170, and Randel, 171-172 Tip Top mine, Stanislaus County, 298, 217 Tobacco Creek prospect, San Luis Obispo County, 239-240 Trans-Oceanic deposit, San Bernardino — see Logan, 200-201 Trask, Parker D., report : Alameda County. — Winegar, 26-27 Authors contributing to Bulletin 152, 14-15 Humboldt County — Live Oak, 70, Prior, 71 Introduction to Bulletin 152, 7-15 Madera County — Agnew Meadows, 103 Production of manganese ore, California, 9-11 Prospecting for manganese, aids to, 11-14 Riverside County, Arlington district, 176-177 San Bernardino County — Orchard, 205-206 San Joaquin Countv — Fabian, 222; see also Lasky, S. G. (and others) , 223-226 ; Pierce, W. G. (and others) , 221-222 Santa Clara Countv — see Simons, Frank S., and, 242-245, 246-247, 248, 251-253, 255-257, 262-263 Scope of report, 7-9 Shasta County— Goat Camp. 266, Nicol. 266 Siskiyou County— Lewis. 275, Walton, 279-280, Wykoff, 280 Stanislaus County— Buckeye, 287-288, Mezzero, 295, Tip Top, 298 ; see also Pierce, W.G., and, 293 ; and Simons, Frank S., and, 286-287, 289-290, 293, 296 Tehama County — Tehama, 301-302 374 MANGANESE IN CALIFORNIA Tnisk, Parker D., report — Continued Trinity Countv— Berthn, 30r>-306, Big Horn No. 1, 30(5, Carr and Carrie, .312-.313. Claim 23, 313, Coldwater, 313, Dahrman, 314, Dry Lake, 31;"), Emma, 31"), Four Point, 317, Hart and Bear, 319, Hij,'h Lead, 319, Ivouella, 322, Lucky Bill, 322, Maufcanese Queen, 323-320, Rainy Day, 332, Stockton, 337, Tan Oak, 338, Vance, 339, White, 340, Wood, 341 ; see also Creasey , and (and others) , 324, 330 , and Cox, Doak C, report : Mendocino County — IJsal, 14(5 , and Crittenden, Max D. Jr., report : Trinity County — Lucky Sunday and Billy Sunday, 323 , and Pierce, W. G., report : San Joaquin County — Ladd-I'uckeye area, 211-221 Stanislaus County — (^rummett-Knox, 291, Sulphur (lulch, 297 Trinity County— Hale Creek, 317-318 , and Shride, A. F., report : Trinity County — Arrowhead and Black Susan, 304, Black Oak. 307, Cedar Springs, 313 , and Simons, Frank S., report : Santa Clara County— Acme Lode, 245-24(5, Black Horse, 247- 248, Keller, 253 Trinity County — Bucking Camp, 312, Kewawaka, 320, Mont- gomery, 330, Schoolhouse, 334, Shell View, 334, Twi.sted Oak, 338-339, AVagon, 339, Wool Mountain, 341 , and Trauger, Fred D., report : Trinity County— Armstrong No. 2, 302-303, Blue Jay, 309-310 , and Wilson, Ivan F., report: Trinity County — Snow Camp, 335 Trauger, Fred I)., map, Blue Jay deposit, 308 ; see also Trask, I'arker D., and, 309-310 Treasure deposit, San Bernardino^ — see Logan, 200-201 Trewick-Houghton prospect, Fresno (bounty, 55-56 Triassic metasediments, Riyerside County, 181 shale, Shasta County, 268 Trinity County, deposits description, 302-341 River, Murphy-Bramlette prospect on, 331 Trinkle and Purcell, Trinity County deposits : Bald Steer, 304, see Little Deer, 320-321 Triple Jump claim, Santa Clara County, 203 Tripp, Harold — Black Mike claim, Stanislaus, 286-287 Troeger, Roy C. — Black Dream dejiosit, Inyo, 81 Tulare County, deposits description, 341-342 Tule Creek, Two Sugar Pines deposit on, 339 Tuolumne County, deposits description, 342-347 Turner prospect : San Bernardino County, 207, San Diego County, 211, Santa Clara County, 263 , M. C. — Pilot Knob prospect. Imperial, 77 Turtle prospect, Imperial County, 77 Twisted Oak deposit. Trinity County, 338-339 Two Sugar Pines (leix)sit, Trinity County, 339 Two Trees prospect, Mendocino County, 145-146 Tyrer and lOrskine — Rainbow I^edge prospect. Lake, 97 U Ukiah prospect, Mendocino County, 146 Underwood, Henderson and associates — Death Valley claims, Inyo, 81-82 Union C'hrome Co. — Staneuche mine, San I^uis Obispo, 237-239 U. S. Bureau of Mines, Ladd Buckeye area exploration work, 212 , Murmac group, Santa Clara County, 256-257 Geological Survey, report : Alameda County — Graves, 21, Livermore, 22, Mount Hamilton, 24 Amador County — Martell, 31 Butte County — Black Raven, 36, Lashhough and Foley, 36, Smithwick and Noble, 37 Calaveras County — Sunshine, 47 Fresno County — Sunset and Sunrise, 55 Glenn County — Elephant Hill, 58-59, Levensaler and Speir, 62 INDEX 375 U. S. Geological Survey, report — Continued Humboldt County — A.B.C., G3, Burns, 63-64, Martin and Murphy, 71, Mur- phy, 71, Red Knoll. 71 Imperial County — Anson, 73, Pilot Knob, 77 Inyo County— Campbell, SI, Orr, S3, Runge, 83 Kern County — Big Indian, S4, Walsh and McClaude, 87 Ladd-Buckeye and Black Wonder areas, 211-221, pi. 4 Lake County— Bell. 87 Madera County— Scott, 104 Mendocino County — Fischer, 120, Leona, 127, Skaggs Spring, 137, Ukiah, 146 Mono County — Miami, 151 Marin County — Fort Baker, 105, Knute, 105 Napa County — Conn Valley. 158, Hastings, 158 Nevada County— Black Squirrel, 162, McCarty, 164 Placer County — Yankee Jims, 172 Plumas County — Banner, Barrington, and Crabtree, 172, Rush Creek, 175 Riverside County — Box Canyon, 182, Clark and Losekamp, 182, Pinkham, 185 San Bernardino County — Andreen, 188, Turner, 207, Vivian, 208 San Diego County — Ramrod, 209 San Luis Obispo County— Hill. 231. Thompson, 239, Young, 241 Santa Clara Countv— Avery, 246, Billv Goat, 246, McCoy, 255, McPherson, 255, Miller, 255, Turner, 263 Shasta County — Arps, 265, Duncan Creek, 266, Exposed Treasure, 266 Siskiyou County — Kappler, 275 Stanislaus County — Hamilton, 291, Smith, Jack, 292-293, Thompson Bros., 298 Tehama County— Logan, 299-300 Trinity County— Big Horn No. 2, 306, Blue Lizard, 310, Broken Hammer, 312, Corner, 313, Rice Road, 333, Shell View, 335, Wagon, 339 Tulare County— Gill Ranch, 342 Tuolumne County — Flaming Arrow, 342 U. S. Gipsum Corp — Langdon deposit, Riverside. 183-184 University of California, Manganese Queen investigation, 326, 329 Usal deposits, Mendocino County, 146-147, analyses table, 146 V Valle, Dr. C. C. — Engineer's Spring deposit, San Diego, 208 Valley View deposit, Plumas County, 176 Van Doren, C. S. — Big Reef deposit, San Bernardino, 188-191 Horn and Burckhardt — -Black Prince group, San Bernardino, 192-193 Winkle, Walton — Mt. Hamilton prospect, Alameda, 24-25 Vance claims. Trinity County, 339 , William — Black Raven prospect, Butte, 36 , and associates — Carr and Carrie claims, Trinity, 312-313, Cliff deposit. Trinity, 338 and Barnes, Trinity County deposits : Dry Lake, 315, Manganese Queen, 323- 330, Two Sugar Pines, 339 Vanella deposit, Calaveras — see Kellogg, 45-46, and Murphys district. 43-44 Vaneman, S. A. — Thornberry deposit, Madera, 105 Vann Ranch prospect. Lake County, 98 Vesta deposit. Trinity — see Vance, .339 Victor mine, Shasta County, 271 Victory Manganese Mines Co., Trinity County deposits : Armstrong Nos. 1-3, 302-.304. Double-A, 314-315 View Point property, Butte County, 38 Vinton and MacMillan — Earl W. Long prospect, Mendocino, 129-1.30 Vivian deposit, San Bernardino County, 208 Vollmer prospect, San Luis Obispo County, 240 Von Glahn prospects. Lake County, 98-99 Lankin, Hans — Black Raven group, San Bernardino, 193-194 Vose, G. W. — Big Gulch claim, Amador, 27 376 MANGANESE IN CALIFORNIA W Wade deposit, Monti — see Mono No. 7, ir)l-ir(2 WiiRon prospects, Trinity County, IWO Waldteiifel liros., Richardson, and others — Wild Devil mine, Mendocino, 147-148 Wallace prospect, Napa County, Kil Ranch deposit, Santa Clara County, 264 Walsh and McClaude, Kern County, 87 Mendenhall — Buck Rid^e prospect, Mendocino, ll.') Walton prospect, Siskiyou County, 270-280 War Baby deposit, Inyo County, 83 Manganese Co., Imperial County, 78-79 Ward deposit. Trinity — see Weed, .^40 Ware deposit. Trinity County, .330,340 Warm Springs Creek, O'Connell prospect on, 284 Warner property, Sonoma County, 285 Warren, Charles R., report : San .Toaquin County — see Lasky (and others), 223-220 Trinity County — Bear Ridge, 304, Big Boy, 300, Blue .Jay map. .308. Briggs, 311-312, Coyote, 313-314, Lampley, 320, Lookout, 321, Ivost Mine, .321-.322, Plummer Peak. 3.32, Ware, .3.30-340 Warren, James and Joseph — Windhigler No. 1 deposit, Humboldt, 72 , J. P., deposits : Humboldt — Fort Seward, 6t>, 68-60, Stanislaus County — Ham- ilton, 201, Jake Smith, 202-203, Section 23, 297, Trinity County —Blue Jay, 308, 300-810, Lucky Sunday, 323 Wasp-K.D.H. deposit, Santa Clara — see Billy Goat, 246 Wayland Ranch deposit, Monterey County, 154 Weed prospect. Trinity County, .340 Weeks, F. P. — Hoist- Weeks prospect, Sonoma, 284 Welch mine, San Luis Obispo County, 240-241 Well-Earned deposit. Imperial — see Pilot Knob, 77 West Coast Chrome Co. — Murmac group, Santa Clara, 256-257 Metals, Ltd., Siskiyou County deposits: Chaparral Hill, 272-273, Scott River, 279 prospect, Tuolumne County, ,345 and Shaw prospect, Plumas County, 170 Western Manganese Co., Santa Clara County deposits : Jones, 251-253, Mexican, 255 Whedon Manganese Mines, Imperial County, 79-80 Wheeler prospect, Sonoma County, 285 Whipple Mountains, deposits in : Monument King, 202, Stewart, 206 White Bear deposit, Siskiyou — see Mayland, 276-277 deposit. Trinity County, .340 , Mrs. .1. Q. — Brereton mine, Mendocino, 113-114 , Mildred M. — Last Hope claim, Trinity, 320 Oak prospect. Trinity County, 341 , William P. Estate (Ranch) , Trinity County deposits : Big Horn, 306, Blue Lizard, 310, Broken Iliimmer, 312, Cold- water, 313, Corner, 313, Kekawaka, .320, Montgomery, ;i30. Shell View, 3.34-335, Schoolhouse, 334, Summit. .337 ; see also 340 White-0-Ranch deposit, Sonoma County, 285-280 Whiteman claim. Trinity County. .340 Wilbur, Agnes — Mary Lue claim. Trinity, 3.30 Wild Devil mine. Mendocino (bounty, 147-148 Wildwood and Dubakclla King deposit. Trinity — see Skaggs, 335 Williams, Nathan — Flaming Arrow prospect, Tuolunnie, .342 and Sousa — Black Mountain jirospcct, San Luis Obispo, 229 Wilson, C. L. — Arps jirospect, Shasta. 205 , Donahue, McFarland — Sunbeam mine, Stani.slaus, 297-298 , Ivan F., report : Amador County — Alexander, 27, Big Culch, 27. Custer, 27-28, Deaver, 28, Du Frene, 28-29, Eagle's Head, 29, Germolis, 30, Jones, .30-31, Lubanko, 31, Pereni, 31-32, Peyton, 32-33, Stirnaman, 34-35 INDEX 377 Wilson, Ivan F., report — Continued Butte County — Binet, 35-36, Josephson, 36, Shamberger, 36-37, Sunny Park, 38 Calaveras County — Airola, 38-40, Big Little Bear, 40, Callahan, 40-41, Carley, 41, Cave City, 41, Daniels, 41-42, Fortner Ranch, 42-43, Joses, 45, Kellogg, 45-46, Lavagnino, 46, Soapstone, 46-47 El Dorado County — David, 51-52, Martinez, 52, Mocettini, 52-53 ; see also Taliaferro, N. L., and, 51 Fresno County — McMurty, 54 Glenn County — Big Stony Creek, 56, Brown & Moore, 57, B. S. No. 1, 57-58, Hummingbird, 59, K. B. Nos. 1 and 4, 59-62, Rattlesnake, 62-63 Imperial County — Claim unnamed, 73, Chocolate Drop, 74-76, War Manganese, 78-79 Inyo County— Lillie, 82-83 Kern County— O. K., 85, Shamrock, 85-86, Snowy, 86-87 Los Angeles County— Black Bros., 100-101, Purple Sage, 101-102, Red Feather, 102-103 Madera County — Stewart and Nuss, 104-105 Mariposa County- Caldwell, 106-108, Donnelly, 108-109, Gale, 109, Kelm, 109-110, Robie, 110, Strickland, 110-111 Mendocino County— Brereton, 113-114, Harms, 123-125, Knight, 126- 127, Long, Earl W., 129-130, Long, F. J., 130, Rose, 136, Row- lison, 136, South Thomas, 137-139, Wild Devil, 147-148, Wish- bone, 148-149 ; see also Simons, Frank S., and, 116-118, 126 Mono County — Black Horse, 150-151, Champion, 151, Mono Man- ganese No. 7, 151-152, Taylor property, 152-153 Nevada County— Arnold, 161-162, Gleason, 162, Manga-Chrome, 162- 164, Mebam, 164-165, Paine Bros., 165, Pharo, 165, Ryan, 166-167, Santo. 167, Smith, 167-168 Placer County— Gold Hill, 169-170, Lloyd, 170, Pettigrew-Stafford, 170-171, Randel, 171-172 Riverside County — Beal-McClellan property, 180-182, Giant Chief, 183, Langdon, 183-184, Mountaineer, 184-185, Paddy Faulk- ner, 185 San Benito County — Chambers, 185-186, McCreary, 188 San Bernardino County— Big Reef, 188-191, Black Beauty, 191, Daw- son, 194-195, Lee Yim, 195-196, Logan, 200-201, Monument King, 202-203, Moulton, 203, Stewart, 206-207 Shasta County— Nigger Hill, 266-267 Stanislaus County — Coast Manganese, 290, Section 23, 297 Tehama County — Manganese Peak group, 300-301 Trinity County — American Manganese, 302, Big Buck, 306, Big Rock, 306-307, Black Hawk, 307, Black Rock, 307, 309, Gool Nos. 2 and 3, 317, Jaybird, 319-320, Jewett, 320, Last Chance, 320, Manganese claim, 338, Whiteman, 340 Tulare County— Barbour, 341-342 Tuolumne County— Hughes, 343-344, Jasper, 344, Pedro, 344-345, Schoettgen, 345, Windeler, 345-346, Wonder, 346-347 Yuba County— Bean, 347-348 , and Crittenden, Max D. Jr., report : Mendocino County — Thomas, 142-145 , and Hadley, J. B., report : Imperial County — Whedon, 79-80 Windbigler Nos. 1 and 2 prospects, Humboldt County, 72-73 Windeler claims, Tuolumne County, 345-346 Winegar mine : Alameda County, 26-27, Santa Clara County, 264 , Phil — Section 14 mine, Alameda, 26 and Most — Man Ridge mine, Alameda, 23 Wingate Wash deposit, Inyo County — see Black Dream, 81, and War Baby, 83 Winship-Doak (-Donovan), Alameda — See Chaney lease, 18-19 , K. D., Estate : Santa Clara County deposits — Winegar, 264, Winship leases, 264-265 ; Stanislaus County deposits — Thompson Bros., 298 378 MANGANESE IN CALIFORNIA Wishbone deposit, Mendocino County, 148-149 Witter Springs mine, Lake County, 99-100 Wolcott and others — Moore Creek prospect, Napa, 158-159 Wonder mine, Tuolumne County, 346-347 Wood deposit. Trinity County, 341 Wood and Braun — Rhodonite claim, Siskiyou County, 278 Woodford, A. O., report : Humboldt County — Janes Creek, 69-70; see also Davis, E. F., and, 66, 67-68 Lake County— see Davis, E. F., and, 95-97, 99-100 Mendocino County— see Davis, E. F., and 115, 119-120, 125, 127-129, 132-134, 139-142, 149-150 Trinity County— see Davis, E. F., and, 304, 320-321, 332-333 Woodman Station deposit, Mendocino — see Earl W. Long, 129-130 Woods claim : Fresno County, 56, Humboldt County — see Charles Mountain, 64-65, Trinity County, 341 Wool Mountain claims. Trinity County, 341 Wooley, George W. — Bear Canyon deposit, Butte, 35 World War No. 2 deposit, Humboldt — see Sam Brown, 71-72 Wren Ranch deposit, Nevada — see Mangatop, 164 Wright, M. A. — Liberty mine, Stanislaus, 293 prospect, Sonoma County, 286 Wykoff prospect, Siskiyou County, 280 Y Yankee Jims deposit. Placer County, 172 Yoeman, Stevens, Bryan — New deal mine, San Bernardino, 203-205 Yolla Bolly deposit. Trinity— see Bertha, 305-306 Mountain : Dahrman group on, 314, Emma group on, 315 You Bet deposit, Nevada — see Ryan, 166-167 Young mine : Mendocino County, 149-150, San Luis Obispo County (deposit) , 241 Yuba County, deposits description, 347-348 Z Zappone and Lesher — War Manganese Co., Imperial, 78-79 Zurcher prospect, Calaveras County, 47 ; see also Murphys district, 43-44 11208 7-49 2M JUL 2 9 1983 THIS BOOK IS DUE ON THE LAST DATE STAMPED BELOW AN INITIAL FINE OF 25 CENTS WILL BE ASSESSED FOR FAILURE TO RETURN THIS BOOK ON THE DATE DUE. THE PENALTY WILL INCREASE TO SO CENTS ON THE FOURTH DAY AND TO $1.00 ON THE SEVENTH DAY OVERDUE. •6< JAM e 1969 !JIAN4 1973 AUG2 7REC'D .v.^ RECEIVED JUL 1 9 1983 PHYS SC! LIBRARY JAN 7 1»7 RECEIV LIjeRARY, CtOI^IiEGE OP AGRICUIiTDRE, DAVIS ^ UNTVERSITT OF OAIilFORNIA Book Slip-10wi-8,'49(B5851s4)458 PHY5 blw-i LiDnAHV 3 1175 00672 6544 GEOLOGIC MAP AND SECTIONS OF THE LADD-BUCKEYE AREA SAN JOAQUIN AND STANISLAUS COUNTIES CALIFORNIA GEOLOGY BY To»oo>oo«ie boi. mod, from o,„o. I 'ii'iiihirr^ '''i^mmmiBIMik < z ( 3 *^ I C^ .9- +J Q-^J3 4j ^-o it OLAF P. JENKINS, Ch.e STATE OF CAIIFORNIA DEPARTMENT OF NATURAL RESOURCES PLAN OF UNDERGROUND WORKINGS GEOLOGIC SECTIONS OF THE LADD MINE SAN JOAQUIN COUNTY, CALIFORNIA SW stope ow^f N£ A ^^--^ ' 'if ''^ ~~~~~~1 ^-y^ - / ; fcjfls'^ff \ ^''\^"': /#S<'"' ^\lm ^'"^' ] ^^'^ /#/ // \ ^'<^^ 1 ■^% tV // X ' ^e ^, '^ts 1 ; / LOWEfti^UNHEL LEi^£^ V \J(i A " x^- Reprlfiteil from U S Geologicol Survey Preliminory Mo o ^ I " »^l ?S^! < 5 ,? % S 1° s° i" s' < '///y ■ ■ ■ ... a ;t'; ■i y z 1 ■!'^. X ''V// v^ lij v/.'.\ 1 1. : .1 . ".V.I L_J L'jd 1 DIVISION OF MINES OLAF P. JENKINS. Chiel STATE OF CALIFORNIA DEPARTMENT OF NATURAL RESOURCES UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY VERTICAL PROJECTION OF THE LADD MINE SAN JOAQUIN COUNTY, CALIFORNIA PLANE OF PROJECTION NZS'SO'W EXPLANATION Eost ore bed slope vsisx] West ore bed slope LOWSff (SPRING) TUNNEL El 900 BY C R WARREN, 1941 DIVISION OF MINES OLAF P. JENKINS, Chief STATE OF CALIFORNIA DEPARTMENT OF NATURAL RESOURCES UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY h'h BULLETIN 152 - !^' PLATE 10 MAIN ADIT El. 1038 GEOLOGIC MAP OF THE MAHONEY MINE SAN JOAQUIN COUNTY, CALIFORNIA By Max D Crittenden Jr. JULY 1944 LEGEND Shale ond sandstone Manganese oxide ore I8"-Z4" partially oxidized monganiferous chert Raise from 1060 level. DIVISION OF MINES OLAF P. JENKINS, Chief STATE OF CALIFORNIA DEPARTMENT OF NATURAL RESOURCES UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY UtULUUI BULLETIN 152 PLATE 11 MINES AND PROSPECTS 1 C«dor tree (2 c aimit 16 Mory LOU No 1 2 Antonio 17 Block Bolt 3 Black Horia IB Murmac group 4 Keller No. 1 mm a-Mufmoc 5 Meiicon Prospe ctsfab b-Murmoc No 6 Blockbi'd C'Murmac No 7 Moy Be d-Potlerion e Block Eagle e-Chrcogo 9 Tnple Jump 19 Park group 10 Colton-ood 20 Jones group II Queen Bee No 21 Magnesile mme (2 Acme Lode 22 Phoenii Quicksi 13 Look Out m>ne(abandone 14 Ooim 14 23 Lucky Gifl 15 o-Bloch Mike Chromite mine b-Block Point 24 Adobe Conyon REPRINTED FROM U. S. GEOLOGICAL SURVEY PRELIMINARY MAP lOOO TOPOGRAPHIC MAP OF THE BLACK WONDER AREA, SANTA CLARA AND STANISLAUS COUNTIES, CALIFORNIA SHOWING LOCATION OF MANGANESE DEPOSITS UJ a: < CO z DER RNIA o 22 C3 o^ LlI 0) 5g Q 7 :^^"- < oi ^ CL edded shale and chert Arrow indicates dip of fault Strike of vertical fault Strike and dip of beds o Open pit •^cff 3fe.a£>oi/v f/oor of cut PLAN OF UPPER LEVEL (MAIN ADIT) AND OPEN CUT, WITH GEOLOGY PROJECTED TO ALTITUDE OF 2737 FEET „... ^<^imif'' J77«' ^^ ^^-^^^^•Yiliilmi' „-'^^^^'' ' sch. ■;; ^^C^^C-- .«-<£'^^5-~i^V--" "" ^.-i^^^-^"^ ^ X- S74S'-. \ / p 1 ff^ ,../ ^^ 'p^^^^i, . \ z^- v"^ "v, / 5^^ -c '/ ' ^""^^ V ,¥i^|__^_^ •X A Section C-C SEE NEXT PLATE FOR SECTION D-D Section SS' PLAN AND SECTIONS JONES MINE, BLACK WONDER AREA SANTA CLARA COUNTY, CALIFORNIA (PART I) MAPPED BY FRANK S.SIMONS DIVISION OF MINES OlAF P. JENKINS. Ch. STATE OF CAUFORNIA DEPARTMENT OF NATUBAI RESOURCES VERTICAL PROJECTION OF WEST ORE BED GEOLOGY BY MAX D CRiTTENOEN FROM U S. GEOLOGICAL SU SECTION D-D PLAN AND SECTIONS OF THE MINE WORKINGS OF THE JONES MINE BLACK WONDER AREA, SANTA CLARA COUNTY, CALIFORNIA. PART 2 DIVISION OF MINES OLAF P. JENKINS, Chief STATE OF CALIFORNIA DEPARTMENT Of NATURAL RESOURCES UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY CEQIOCI BULLETIN 152 PLATE 15 /.„- EXP1„ANATI0N / ( I I ,,N DEPOSIT I WK-.I |S| i ; I ^ NO. 4 , ^ _^J^ E3 J.UpLnrown side; D.Do*i thrown Strike of vertical fault Strike and drp of beds Strike of vertical beds Axis of anticline — Hi Axie of syncl.'ne Inclined shaft -K Open cut Open pit Dump Section S-B' in face of cut 2 DEPOSIT NO. Z A'1/<>7,\^ ■.;v^"i '^" X - Section C-C Section Xl-D' DEPOSIT NO I Fi!«t REPRINTED FROM U 5 GEOLOGICAL SURVEY PRELIMINARY GEOLOGIC MAP AND SECTIONS OF THE MURMAC DEPOSITS, BLACK WONDER AREA, SANTA CLARA COUNTY, CALIFORNIA UNITED STATES DEPARTMENT OF THE INTEBIOR GEOLOGICAL SURVEY GEOLOGIC AND TOPOGRAPHIC MAP AND UNDERGROUND WORKINGS OF THE AHO MINE SONOMA COUNTY, CALIFORNIA Sections 15-16, T8N , R I2W. M DM EXPLANATION ond geology by October 1942 UNDERGROUND WORKINGS LOWER WORKINGS DIVISION OF MINES OLAF P. JENKINS. Chief STATE OF CALIFORNIA DEPARTMENT OF NATURAL RESOURCES UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY BULLETIN 152 PLATE 17 Undifferentiated red and white chert Manganese ore Man^aniferous outcrop North ore bed. upper level wori^ings Northorebed. lower level workings Inferred position of north ore bed at upper level Inferred position of north ore bed at lowerlevel Approximate stratigraphic horizon in chert FaTTlt" ■^30 Strike and dip of beds Strike and dip of vertical beds Strike and dip of overturned beds Axis of £_yncline — < Adit o Col lar of diamond-drill hole (D.D.H.) Contour interval 25 feet Datum is mean sea level GEOLOGIC AND TOPOGRAPHIC MAP OF THE BUCKEYE MINE AREA STANISLAUS COUNTY CALIFORNIA GEOLOGY AND TOPOGRAPHY BY W G PIERCE ,941 DIAMOND DRILLING BY BUREAU OF MINES DIVISION OF MINES OLAF P. JEN KINS. Chief STATE OF CALIFORNIA DEPARTMENT OF NATURAL RESOURCES UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY Mil holt 3 mas dtflectaa Indicated undlfftf«ntlalad SECTION ALONG A-A SCALE Manganese ore of North Ore Body: Mostly blacit oxides above £lev 1900. mostly primary rhodochroslte, hausmannite and manganese silicates below I900 level EXPLANATION M Morgonese or /" Strike ond dip of beds or w (^2^jX Open cut = Shear zone Feet between footwoM and hanging wait of stope Top of roise or winze J>^ Foulf showing dip a Bottom of raise or winze Js^ Anis of onticli e ZH) Ore chute ^ Axis of synclir e DDH 3 U S Bureou of Mines Diamond drill hole NORTH ORE BED GEOLOGY BY MAX D. CRITTENDEN , OR,, 1944 ; S.G. LASKY CHARLES R. WARREN AND FRANK S.SIMONS, 1940-41 ,„.,„\:^> rrrri\ri:r„< of oiide or, ■20 FOOT LEVEL GEOLOGIC MAPS AND SECTION NORTH AND SOUTH ORE BEOS BUCKEYE MINE STANISLAUS COUNTY, CALIFORNIA SOUTH ORE BED DIVISION OF MINES OLAF P. JENKINS. Chief STATE OF CALIFORNIA UNITED STATES DEPARTMENT OF THE INTERIOR DEPARTMENT OF NATURAL RESOURCES GE OLOGICAL SURVEY BULLETIN 152 PLATE 19 EXPLANATION tone and shale W^ Manganese bed Fault showing dip Strike and dip of beds Strike and dip of vertical beds Strike anddip of overturned beds REPRINTED FROM U S GEOLOGICAL SURVEY PRELIMINARY MAP Plan of n-iine tunnel X Prospect pit //(^^^^ Mine dunnp Contour interval 25 feet Datum is mean Sea level GEOLOGIC AND TOPOGRAPHIC MAP OF THE LIBERTY MINE AREA STANISLAUS COUNTY, CALIFORNIA GEOLOGY AND TOPOGRAPHY BY W.G.PIERCE 19 41 UNITED STATES DEPARTMENT CF THE INTERIOR GEOLOGICAL SURVEY (Rguresshow widthinfeet) PLAN AND VERTICAL PROJECTION LIBERTY MINE STANISLAUS COUNTY, CALIFORNIA GEOLOGY BY W G PIERCE S, C CREASEY AND P D. TRASK 1941 REPRINTED FROM U S GEOLOGICAL SURVEY PRELIMINARY MAP „TED STATES DEPARTMENT OF THE INTERIOR r-.pninr,ICAL SURVEY, BULLETIN 152 PLATE 1 EXPLANATION f \1^ 1