mm Digitized by the Internet Archive in 2012 with funding from University of Illinois Urbana-Champaign http://archive.org/details/highcalciumlimes55723lama STATE OF ILLINOIS DEPARTMENT OF REGISTRATION AND EDUCATION DIVISION OF THE STATE GEOLOGICAL SURVEY M. M. LEIGHTON, Chief REPORT OF INVESTIGATIONS- NO. 23 HIGH-CALCIUM LIMESTONE NEAR MORRIS, ILLINOIS BY J. E. LAMAR AND H. B. WILLMAN ^^-K&Ys^ PRINTED BY AUTHORITY OF THE STATE OF ILLINOIS URBANA, ILLINOIS 1931 STATE OF ILLINOIS DEPARTMENT OF REGISTRATION AND EDUCATION M. F. Walsh. Director BOARD OF NATURAL RESOURCES AND CONSERVATION M. F. Walsh, Chairman Edson S. Bastin, Geology William A. Noyes, Chemistry John W. Alvord, Engineering William Trelease, Biology Henry C. Cowles, Botany Charles M. Thompson, Representing the President of the University of Illinois STATE GEOLOGICAL SURVEY DIVISION M. M. Leighton, Chief Jeffersons Printing & Stationery Co. Springfield, Illinois 1931 Contents Page Synopsis 7 Introduction 9 Acknowledgments 10 Detailed description 10 Geologic features 10 Lithologic character 10 Physical character 13 Chemical composition 13 Thickness 17 Overburden 17 Factors governing distribution of limestone and overburden 18 Quantity of stone available 18 Quarrying conditions 19 Recommendations for exploration 20 Other areas underlain by limestone 20 Uses of Divine limestone 20 Flux 21 Lime 21 Portland cement 21 Agricultural limestone 22 Limestone for alkali manufacture 23 Limestone for sugar refining 23 Limestone for paper manufacture 23 Poultry grit and mineral food 23 Mineral filler 23 Limestone for rock dusting in coal mines 24 Aluminum refining 24 Stucco, terrazzo, and artificial stone 24 Other uses 24 Building stone 24 Glass 25 Whiting substitute 25 Other possible uses 26 Illustrations Figure Page 1. Map showing location of Divine limestone 8 2. An exposure of weathered limestone 11 3. Bedrock map of Divine area 12 4. Topographic and areal geology map of Divine area 16 Tables 1. General sequence of strata in vicinity of Divine 11 2. Physical analyses of Divine limestone 13 3. Chemical analysis of Divine limestone 17 4. Estimates of quantities of limestone 19 5. Limestone used or sold in 1929 14-15 6. Analyses of clays 22 HIGH-CALCIUM LIMESTONE NEAR MORRIS, ILLINOIS By J. E. Lamar and H. B. Willman SYNOPSIS Two deposits of high-calcium limestone occur in Grundy County, Illinois, located less than 60 miles by rail from Chicago and immediately adjacent to the Elgin, Joliet and Eastern Railroad and the Illinois Waterway (fig. 1). Their favorable location with reference to transportation and their proximity to Chicago, which has but few nearby commercial sources of high-calcium limestone, make them of especial interest to producers and consumers of this type of limestone. The larger or south tract lies south of the Illinois River and comprises an area of about 1700 acres in which the stone has a known maximum thick- ness of 44 feet, an estimated average thickness of about 21 feet, and over- burden averaging less than 10 feet thick. It is estimated that this tract con- tains 133,000,000 tons of stone, of which 91,000,000 probably have less than 3^2 feet of overburden. Because this tract adjoins the Dresden Island Lock and Dam of the Illinois Waterway it may be that only the southern half or two-thirds of its area will be available for quarrying involving heavy blasting. It is understood that the dam is intended to raise the level of the water to an elevation of 505 feet at the dam. This level is believed to be somewhat higher than the limestone area in parts of sees. 26, 25, and 36. The smaller or northern tract lies north of Illinois River and contains limestone from a few to 36 feet thick. At some places the stone crops out ; at others it is covered by overburden as much as 15 feet thick. This tract is estimated to comprise about 280 acres of stone having an average thickness of about 21 feet with an average overburden less than ten feet thick, and to contain approximately 21,000,000 tons of limestone, of which 14,000,000 tons probably have an overburden less than 3^ feet thick. Additional stone may possibly be obtained by sub-surface mining under the uplands to the northeast of both the north and south tracts. (See topo- graphic and geologic map, fig. 4.) The analysis of a sample of slightly weathered stone shows that it con- tains more than 95 per cent calcium carbonate, and the unweathered stone doubtless contains an even higher percentage of calcium carbonate. The JOLIET -Jia MILES CHICAGO - 55 MILES MINOOKA- 3 MILES CRI4P HH - 3 MILES CHICAGO - 55 MILES MINOO KA- 4 MILE S - Fig. 1. Map of Divine area showing various pertinent geographic features, the position and probable extent of the two tracts of high-calcium limestone, the location of lime- stone outcrops and of borings, and skeletal records of borings. The area included in the two tracts is thought to be underlain by limestone averaging at least 21 feet thick and having an overburden averaging less than 10 feet thick (Table 4). 8 INTRODUCTION" ? deposit as a whole is probably a uniformly high-calcium stone suitable for flux, lime, and agricultural limestone. Some of it may be white enough for whiting, and some of it may be used as commercial marble, as the stone pol- ishes well and occurs in shades of gray, buff, pink, and perhaps white. According to available analyses the rock is low in magnesium carbonate, is located not far from clay deposits that are also low in magnesium carbonate, and mav overlie a non-magnesian shale, all of which conditions appear favor- able for cement manufacture. The stone is somewhat soft and probably cannot be recommended for use as concrete aggregate for road construction, or as railroad ballast. The top and bottom surfaces of the limestone are uneven. Locally erosion channels may cut well into or even through the stone, thereby devel- oping depressions in the upper surface or isolating certain portions of the limestone. Thorough test drilling of the deposit before commercial exploita- tion is begun is recommended. INTRODUCTION The constructional and industrial needs of metropolitan Chicago have created a tremendous demand for both magnesian limestone, commonly called dolomite, and limestone composed almost exclusively of calcium carbonate known as high-calcium or calcitic limestone. The Chicago district, however. lies in a portion of Illinois that is underlain almost exclusively by dolomite and although this stone admirably serves many purposes there are others, such as cement, and high-calcium lime and flux, for which high-calcium lime- stone is desired. In view of this situation, unusual economic importance may be attached to the occurrence of a deposit of high-calcium limestone in eastern Grundy County, a few miles east of Morris, Illinois (fig. 1). located less than 60 miles from Chicago either by rail or water and lying along the Elgin, Joliet, and Eastern Railroad and the Illinois Waterway. This deposit has been described in a general way in previous reports. 2 The present study brings together the earlier data and newer information obtained from a recent study of the deposit made in connection with a general investigation of the mineral resources along the Illinois Waterway. Quarrving of this deposit may involve costs somewhat above the average because the limestone is not as thick or as regular as is considered ideal. How- ever it seems likely that any additional costs on this account will be offset, largely, so far as competitive sales in the Chicago market are concerned, by the short haul and potential low cost of transportation to that market. 2 Krev, Frank, and Lamar. J. E., Limestone resources of Illinois: Illinois State Geol. Survev Bull. 46, pp. 115-116, 1925. Culver, H. E., Geology and mineral resources of the Morris quadrangle: Illinois State Geol. Survey Bull. 43-B. pp. 33-35, L922. 10 DIVINE LIMESTONE ACKNOWLEDGMENTS The writers are indebted to the Waterway Division of the Department of Purchases and Construction of the State of Illinois, who kindly permitted the use of data obtained from borings made in connection with the construc- tion of the Dresden Island Lock, and to Mr. T. F. Anderson, well driller of Morris, Illinois, who furnished many records of wells drilled in the region covered by this study. Considerable data were obtained from Bulletin 43-B of the Illinois State Geological Survey, "The Geology and Mineral Resources of the Morris Quadrangle," by H. E. Culver, published in 1919. DETAILED DESCRIPTION' Geologic Features The limestone is a part of the Cincinnatian series (Richmond forma- tion) in the Ordovician system and is herein named the "Divine limestone" because it occurs in the vicinity of Divine station on the Elgin, Joliet, and Eastern Railroad. The Richmond formation consists largely of shale but locally contains strata of high-calcium limestone, dolomite, and shaly lime- stone. The maximum recorded thickness of any bed of Richmond limestone in northeastern Illinois is about 80 feet, 3 but the Divine limestone comprises the thickest high-calcium bed known within the Richmond formation, attain- ing a known maximum thickness of 44 feet (fig. 1. boring in SW. corner of the NW. Y\ sec. 36, T. 34 N., R. 8 E.). The formation dips or lowers to the northeast and has a northwest-southeast strike, as is roughly indicated by the western edge of the area of outcrop of relatively thick stone (fig. 4. p. 16). The base of the limestone is shown to be uneven by the variations in its ele- vation which are departures from the normal northeast dip of the formation (fig. 1). The Divine limestone is underlain by Richmond shale, normally 50 to 70 feet thick although as little as 15 feet of shale is reported to occur at some places. The limestone is overlain by recent or Pleistocene alluvium or by shale or clay, usually of Richmond age but locally of early Pennsylvania!] (Coal Measures) age. The overlying shales are relatively thin near the out- crop of the limestone, but thicken to more than 50 feet some distance away. Lithologic Character The exposed limestone is generally coarse-grained, crystalline, and us- ually white, light gray, or buff in color, although locally, as immediately north of Divine, it is pink or brown. Where fresh it is composed of strata from 8 to 14 inches thick which commonly weather to slabs from 2 to 4 inches thick 3 Fisher,T">. J., Geology and mineral resources of the "Wilmington quadrangle, Illinois State Geol. Survey. Unpublished manuscript. LITHOLOGIC CHARACTER 11 Table 1. — General sequence of strata in vicinity of Divine Thickness Recent system Feet Silt, sand, gravel and peat 0-10 Pleistocene system Till, clay, silt, sand and gravel 0-60 Pennsylvanian system Carbondale and Pottsville formations Shale, clay, sandstone, and coal 0-50 Ordovician system Cincinnatian series Richmond formation Shale, dark gray 0-7 Limestone (Divine member), coarsely crystalline, fossiliferous 0-44 Shale, calcareous, gray, non-gritty 13-70 Mohawkian series Galena formation Dolomite, light gray, fine-grained .... (fig. 2). Fossils, complete and fragmentary, are common and locally com- prise a major part of the stone. Pyrite was observed but rarely, however it is reported that some of the Divine limestone removed from excavations for the foundations of the Dresden Island Dam contained a large amount of this mineral. No shale or clay strata more than a fraction of an inch in thick- Fig. 2. Exposure of Divine limestone along Elgin, Joliet and Eastern Railroad about a quarter of a mile north of Divine. This outcrop is weathered as indicated by the manner in which the strata are split and broken. DIVINE LIMESTONE Fig. 3. Map of Divine region showing probable areas where limestone or other rock occurs at a depth of less than 2> l / 2 feet. The probable positions of glacial channels of unknown depths are suggested by the blank areas in the south tract. (Modified from the Grundy County Soil Map in "Grundy County Soils," by Smith, R. S., DeTurk, E. E., Raiier, F. E., and Smith. L. H., University of Illinois Agricultural Experi- ment Station, Soil Report No. 26, March, 1924.) CHEMICAL COMPOSITION' 13 ness were noted, and it is thought that the member normally contains no inter- bedded shales. The entire formation is not exposed at any one place, but the lower part is exposed along the south bank of Illinois River near the center of sec. 26, T. 34 N., R. 8 E. The upper part is exposed along the road near the center of sec. 35 of the same township and also in the railroad cut and in the abandoned quarry immediately north of Divine. Physical Character The physical properties of the unweathered Divine limestone are not known in detail hut tests made on a sample obtained from the least weathered outcrop available, namely that in the railroad cut about a quarter of a mile north of Divine, in the center of the north line of sec. 34, T. 34 N., R. 8 E. (fig. 1). gave the following results. Table 2 — Physical analysis of Divine limcstone a Specific gravity 2.68 Weight, pounds per cubic foot 167. Water absorption, per cent 0.59 Water absorbed, pounds per cubic foot 0.79 French coefficient of wear 5.0 Hardness 8.7 Toughness 4.00 Cementing value 40. The results of these tests show that, compared to other Illinois lime- stones and dolomites 4 , the stone exposed in the railroad cut is of average specific gravity and weight per cubic foot, low water absorption, low-medium resistance to wear as measured by the French coefficient, low hardness and toughness, and medium cementing value. Tests on samples of unweathered limestone will probably show a somewhat higher French coefficient, hardness, and toughness, but the Divine stone generally will probably not have a high rating with respect to these coefficients. Chemical Composition Only one complete chemical analysis of the Divine limestone has been made. The sample tested was taken from the outcrops along the Elgin, Joliet and Eastern Railroad about a quarter of a mile north of Divine station, in the center of the north line of sec. 34, T. 34 N., R. 8 E., where about 4 feet of limestone is exposed (figs. 1 and 2). (See Table 3, p. 17.) a Analysis by the Testing Laboratory of the Illinois State Division of Highways. 4 Krev, Frank, and Lamar, J. K., The limestone resources of Illinois, Illinois State Geol. Survey, Bull. 46, pp. 39 and 47-63, 1925. 14 DIVINE LIMESTONE Table 5. — Limestone sold or used by producers in Illinois, Limestone- Flux Sugar refineries .... Glass factories Paper mills Agriculture Concrete and road . metal Railroad ballast .... Alkalie works Asphalt filler Riprap Calcium carbide works Rubble Coal mine dusting Mineral food Poultry grit Whiting substitute . . . Stucco, terrazzo, and artificial stone Building Rough construction Rough architectural Finished, sawed, and cut Lime d Other uses and those for which production is not listed above . Illinois Michigan Quantity Value Average Quantity Value Average tons dollars price tons dollars price per ton per ton 786,000 749,721 .95 7,365,300 12,400 4,599,477 18,800 .62 1.51 b b b b b b b b b 947,800 843,693 .89 182,660 187,500 1.03 5,327,310 4,221,702 .79 2.218,550 1,372,500 936,240 724,302 .77 239,910 158,554 c c c c c c c c e c c c 135,080 132,971 .98 b b b c c c c c c b b b c c c c c c '■ c c c c c c c c e c c e c c c c c c c c c c c 3,310 3,408 'O.ooo 15.000 119,382 972,312 8.15 91,408 844,543 0.23 199,540 257,364 1.29 3,430,700 1,921,103 a Coons, A. T., Stone in 192IT, Mineral Resources of the United states, 1929, Part II, pp. 251-254. I, Less than ?, producers. Statistics not available for publication. <• Xo data available. ,! Indicates production of lime, not limestone. e Quantity in cubic feet. I.IMESTOXE SOLI) OR USED 15 Michigan, Indiana, Wisconsin, and United States in 1929 a Indiana WlSCON SIN United States Quantity Value Average Quantity Value Quantity Value Average tons dollars price per ton tons dollars tons dollars price per ton 132,060 27,397 .21 11,890 9,579 24,337,280 487,990 17,994,110 874,909 .74 1.79 b b b 257,370 273,880 455,367 456,251 1.76 1.66 154,590 176,514 1.14 67,510 122,882 2,654,580 3,764,775 1.42 3,033,890 2,748,016 .91 3,068,750 3,000,198 50,090,350 50,057,122 1.00 467,490 415,490 .89 62,980 51,003 11,374,850 8,877,328 .78 c c c c c 5,004,930 3,234,457 .67 c c c c c 344,880 1,165,538 3.37 109.660 34,422 .31 100,350 113,728 2,080,580 2,655,374 1.28 c c c c c 339,510 236,412 .70 b b b 29,790 101,356 354,480 693,678 1.96 e c c c c 34,650 121,712 3.51 c c c c c 25,270 96,009 3.80 c c c c c 34.600 221,610 6.40 c c c c c 125,430 626,692 5.00 c c c c c 85,540 292,313 3.42 10,370 44.860 178,490 280,564 ^5,349,190 2.935,124 e 144,490 141,907 6,192,550 3.779,639 e9,087,590 15,651,380 ^19,320 86,937 f9,430,100 16,589,054 116,795 786,814 6.74 130,902 830,180 4,269,768 33,578,848 7.84 86,780 111,479 1.28 7,464.870 7.427,900 .99 16 DIVINE LIMESTONE Fig. 4. Topographic and areal geology map of Divine area showing probable extent of the thick and thin Divine limestone and over-and underlying formations. The glacial till locally contains sand and gravel. Topography copied from U. S. Geological Sur- vey topographic map of Morris quadrangle; geology revised from geologic map in "Geology and Mineral Resources of the Morris Quadrangle," by H. E. Culver, Illi- nois State Geological Survey Bulletin 43-B, 1922. Correction on map: the outcrop area shown southwest of the section number "26" should indicate thin Divine limestone (fig. 1, p. 8). OVERBURDEN 17 Table 3 — Analysis of limestone near Divine" Silica 0.94 Calcium oxide 53.73 (Calcium carbonate, 95.88) Magnesium oxide 0.91 (Magnesium carbonate 1.90) Iron oxide and alumina 1.14 Sulfuric anhydride 0.07 Ignition loss 43.57 Despite the fact that this sample came from a weathered outcrop and contained fragments of stone stained by iron oxide, the carbonates total 97.78 per cent and the impurities only 2.15 per cent. Other samples from outcrops near Divine contained 2 per cent or less of residues insoluble in hydrochloric acid. A sample of Divine limestone from a section of diamond drill core' 5 obtained years ago while test drilling in the south half of sec. 2, T. 33 N., R. 8 E. contained only slightly more than 1 per cent of insoluble residue. All data at hand suggest that these tests are probably representative of the forma- tion as a whole. Thickness The Divine limestone ranges in thickness from a few to 44 feet, owing to the fact that both its upper and lower surfaces are irregular. The average thickness is thought to be about 20-25 feet and is probably somewhat greater in the south than in the north tract. Owing to its dip the stone should thicken toward the northeast, although local erosion may cause exceptions to this tendency. Overburden Over a relatively large portion of the area indicated as probably under- lain by workable stone (figs. 1, 3. and 4) the overburden is less than 3 l / 2 feet thick (fig. 3) : its maximum thickness is possibly 20 feet, and the aver- age thickness is about 10 feet. It appears to consist largely of unconsolidated clay, loam, sand, and gravel, which for the most part can probably be readily removed by hydraulic methods of stripping. However, a possible exception occurs, in the north tract in the NW. *4 SE. }i sec. 22, T. 34 N., R. 8 E., where a boring is reported to have penetrated 6y 2 feet of "soapstone" which may be Pennsylvanian shale or clay, although it is more probably glacial till. a Analysis by the Testing Laboratory of the Illinois State Division of Highways. 5 The exact depth at which the section of core was secured and the precise location of the boring are unknown. 18 FACTORS GOVERNING DISTRIBUTION FACTORS GOVERNING DISTRIBUTION OF LIMESTONE AND OVERBURDEN The Divine region (fig. 4) is a part of a broad floodplain in a valley that was carved or eroded in bedrock by great floods which occupied Illinois, Kankakee, and DesPlaines river valleys during glacial times. In some places in this plain the erosion removed the hedrock that overlay the Divine lime- stone, in others it cut unevenly into the limestone or completely through the limestone leaving isolated remnants of irregular distribution. General sites of maximum flood erosion are indicated by the valleys or low swales in the region of relatively thick limestone, particularly in sec. 35, T. 34 N., R. 8 E. (figs. 3 and 4). Similar effects resulted from another period of erosion many millions of years earlier, in the time preceding the deposition of the Pennsylvanian sedi- ments. Although this earlier erosion did not greatly affect the limestone neai Divine it did develop a locally uneven surface and resultant variations in thickness of the deposit, as well as some irregularities of distribution around the margins (fig. 3). Another consequence of the pre-Pennsylvanian erosion and subsequent deposition is the presence of Pennsylvanian strata at the same elevation as that of older beds, a situation which is well illustrated by the abrupt change from Divine limestone to Pennsylvanian strata along a line not far west of Kankakee River, across sees. 25, 36, and 35, T. 34 N., R. 8 E., and sec. 2, T. 33 N.. R. 8 E. Subsequent to the glacial erosion the limestone was covered by silt, sand, and gravel deposited by the glacial floods. This alluvium is as much as 21 feet thick but probably averages less than 10 feet (fig. 3) on the higher por- tion of the area underlain by limestone. Quantity of Stone Available The quantity of stone in the Divine area cannot be accurately calculated at present because the data available concerning the deposit are too meager and incomplete. However, a preliminary estimate of the area underlain by stone and the tonnage contained is here presented (Table 4). This estimate is based on an approximate average thickness of 21 feet of limestone and Z]A feet of overburden: a cubic yard of stone in place is calculated to weigh 2^4 tons. As it is possible that only certain portions of the Divine deposit will be quarried the estimate is presented by sections. QUARRYING CONDITIONS 19 Table 4. — Estimates of quantities of limestone present in the Divine area Section No. Limestone more than 21 feet thick Limestone more than 21 feet thick with less than ZV 2 feet of overburden, (included in preceding column) Limestone of unspecified thickness with less than 3y 2 feet over- burden Limestone with an average thickness of less than 21 feet, with less than 3V 2 feet over- burden Acres Tons Acres North Tom Tract Acres Acres 22 175 13,300,000 90 6,900,000 100 10 27 105 8,000,000 95 7,200,000 100 5 28 5 (Total) 280 21,300,000 185 South 14,100,000 Tract 200 20 25 60 4,600,000 50 3,800,000 60 10 26 365 27,800,000 340 25,900,000 340 27 165 12,600,000 130 9,900,000 130 34 130 9,900,000 70 5,300,000 95 25 35 635 48,400,000 345 26,300,000 345 36 50 3,800,000 15 1,100,000 15 1 10 10 2 340 1,745 25,900,000 250 19,000,000 295 1,290 45 (Total) 133,000,000 1,200 91.300,000 90 Quarrying Conditions Owing to the fact that the Divine deposits lie along" Kankakee and Illinois rivers, the possibility of seepage of river or other water into quarries in the limestone must be considered. However, water wells in the vicinity of Divine are ordinarily drilled to a horizon below the Divine limestone, and the limestone is reported to be dry. Inasmuch as the limestone dips to the east, natural drainage of ordinary rain and snow water away from the work- ing face of a quarry could be obtained by beginning operations in the eastern part of the deposit and extending them westward. It is understood that the Dresden Island dam and locks of the Illinois Waterway which have been built at the east end of Twin, or Dresden Island, in sec. 26, T. 34 N., 8 E. (fig. 1) will raise the water level of Illinois and Kankakee rivers to an elevation of 505 feet at the dam. This will not affect the north tract or that part of the south tract below the dam, but may flood a portion of the eastern part of the south tract, especially in sees. 26, 25, 20 USES OF DIVINE LIMESTONE and 36. The possibility of water seepage or overflow into a quarry will be materially increased but inasmuch as the velocity of Illinois and Kankakee risers will be greatly reduced, probably causing slack-water conditions over most of sees. 25 and 36 and possibly sec. 26, the maintenance of levees to prevent flooding of the quarry would seem reasonably easy. Blasting in the general vicinity of the dam and locks will probably have to be restricted to light shots. The Illinois and Michigan Canal which cuts across the north tract will probably not add seriously to the possibility of seepage, but the division of the deposit into two parts may be disadvantageous to economical quarrying. With the completion of the Illinois Waterway it is possible that the canal, which is little used, will be abandoned and in that case it would no longer constitute a possible obstacle to quarrying. Recommendations for Exploration It is recommended that exploration of both the north and south tracts in- clude thorough core drilling and that the cores be carefully examined and tested to determine the chemical and physical properties of the stone. Results of these tests will form a basis for intelligent quarrying and utilization. Other Areas Underlain by Limestone The Dresden Heights bluffs along Illinois River in sees. 23, 24, and 26, T. 34 N., R. 8 E., are underlain by limestone, but as the bluffs are about 120 feet high (fig. 4) they definitely limit the eastern extent of open-pit quarry- ing. As far as is known they are composed of gravelly clay (glacial till) and unless part of the limestone is left as a roof, conditions for mining beneath the bluffs would probably be disadvantageous. Limited outcrops of Richmond limestone occur at some places along Aux Sable Creek west of Minooka in sees. 3 and 4, T. 34 N., R. 8 E. and in sees. 34, 27, 22, and possibly others, in T. 35 N., R. 8 E. As far as is known the stone in these deposits is thinner, has a heavier overburden, and is less favorably situated with reference to transportation than that in the Divine region. USES OF DIVINE LIMESTONE The potential uses of the Divine limestone are numerous and include among others flux, lime, cement, agricultural limestone, poultry grit and mineral filler. Some of these uses, such as flux and lime, involve quantity production and comparatively little preparation of the stone, whereas others, such as agricultural limestone, poultry grit. etc.. involve a smaller production but necessitate finer crushing or pulverizing. If test borings in the Divine PORTLAND CEMENT 21 area indicate a large deposit of stone an operation combining the production of flux and/or lime with the manufacture of rock specialties such as poultry grit, agricultural limestone, mineral foods, stucco and terrazzo chips and the like may be the most profitable. If, however, the deposit is found unfavorable for large scale development the production of rock specialties may still be profitable. From the rather limited data available, the Divine limestone is thought to be suited to the uses enumerated below. Flux The high-calcium and probably low sulfur content of the Divine lime- stone makes it appear to be an excellent flux for smelting iron. The phos- phorous content of the stone is not known but it is probably low, and in other respects the rock compares favorably with other stone now used for commercial fluxes. The stone is also probably suitable for flux in smelting siliceous copper ores and in the lime-roasting process of desulferizing lead ores. Table 5 shows that in 1929 flux stone in Illinois sold for an average of 95 cents per ton, whereas in Michigan it netted 62 cents per ton. Consider- ably more than half of Illinois' production of flux comes from quarries in the Niagaran dolomite in Cook county which ship to steel mills in the Chicago district. In Monroe and St. Clair counties in the southwestern part of the' State are other important flux producing areas which ship principally to the St. Louis market. Lime The Divine limestone, with the exception of the iron-stained portions of the formation, seems well suited to the manufacture of high-calcium lime because of its purity and high-calcium carbonate content. The most important lime producing centers in Illinois are the Chicago and Quincy districts. The lime manufactured in the Chicago district from local stone is high-magnesium lime, but a large percentage of the State production is made from high-calcium limestone brought to Chicago by boat from the northern part of the Michigan peninsula. Production statistics for lime are shown in Table 5 (pp. 14-15). Portland Cement In Illinois, Portland cement is commonly made from a raw mix of clay and limestone in proportions of about 1 to 3. The purity of the Divine limestone makes it suitable for cement making. Satisfactory shale to mix with it may be obtained from nearby deposits in sees. 10 and 11, T. 33 N., R. 8 E. (Table 6), and possibly from shales underlying the limestone. Analyses of the clays in sections 10 and 11 follow. 21 USES OF DIVINE LIMESTONE Table 6. — Analyses of clays in sees. 10 and 11, T. 33 N., R. 8 E. 1 2 3 Silica 53.48 62.32 63.48 Calcium oxide (lime) 1 32 1 39 86 Calcium carbonate 2.36 2.48 1 54 Magnesium oxide (magnesia) 1.61 1.00 1.36 Magnesium carbonate 2.37 2.09 2 84 Ferric oxide (iron oxide) 7 26 1.96 2 61 Aluminum oxide (alumina) 24.53 25.36 23 30 Sulfur trioxide 3 H j 00 U4 Loss on ignition 8.11 7.14 7.02 Alkalies, by difference 58 23 1. Sample from 9-foot exposure of clay in Haeger Brick and Tile Company pit, X\V. 14 NE. % sec. 10, T. 33 N., R. 8 E. 2. Sample from upper 4 feet of clay exposed in pit of Illinois Clay Products Com- pany, near the center of sec. 11, T. 33 N., R. 8 E. 3. Sample from lower 8 feet of clay in pit of Illinois Clay Products Company, near the center of sec. 11, T. 33 N., R. 8 E Most of Illinois' cement is produced in the vicinity of LaSalle, about 45 miles west of the Divine area, where three companies are producing Portland cement. A fourth plant is located at Dixon. In 1929, Illinois plants sold 7,708,208 barrels of cement valued at $11,134,538 or $1.44 per barrel. Agricultural Limestone Agricultural limestone is pulverized or finely crushed limestone or dolo- mite. Its value from the standpoint of chemical composition is usually meas- ured by its "calcium carbonate equivalent" which in the case of high-calcium limestones is approximately equal to the total amount of calcium and mag- nesium carbonate it contains. Commercial grades usually include stone con- sisting of not less than 90 per cent carbonates. The Divine limestone, with its carbonate content of almost 98 per cent, is an excellent agricultural limestone. The average price of agricultural limestone sold in Illinois in 1929 was 89 cents per ton (Table 5, p. 14). This figure includes the value of a large vol- ume of screenings which are largely a bv-product of limestone crushed for other purposes and sell for 50 to 70 cents per ton. Limestone especially pul- verized for agricultural purposes usually brings a higher price than the Illinois average of 89 cents. For example, current quotations 7 indicate prices from $3.00 to $4.00 per ton for high-calcium limestones crushed so fine that 90 per cent of it passes a 100-mesh sieve. ' Rock Products Magazine, Feb. 2S, 1931. MINERAL FILLER 23 Limestone for Alkali Manufacture Very pure limestones, low in silica, iron oxide, and alumina, are used in the manufacture of alkalies. The purity of the Divine stone makes it ap- pear suitable for this purpose. No limestone for alkali works was produced in Illinois in 1929 but the average price in the United States was 67 cents per ton. Limestone for Sugar Refining Limestones containing more than 95 per cent calcium carbonate and less than one per cent each of silica, iron oxide, magnesia, alumina, sulfur dioxide, and other substances insoluble in hydrochloric acid are used in refining cane and beet sugar. The Divine limestone qualifies well for this use except that the iron oxide content is slightly more than one per cent, an excess so small that it would seem tolerable. No limestone for sugar refineries was produced in Illinois in 1929 but that produced in the United States sold for an average of $1.79 per ton (Table 5, p. 15). Limestone for Paper Manufacture High-calcium limestone is employed in the tower system of the sulfite process of paper manufacture. The Divine stone is doubtless suitable for this purpose. No limestone was produced for paper manufacture in Illinois dur- ing 1929. The average price per ton of limestone sold for paper manufacture in the United States in 1929 was $1.66 (Table 5). Poultry Grit and Mineral Food Finely crushed or pulverized limestone, high in calcium and low in mag- nesia, is used as poultry grit to furnish calcium carbonate for the formation of egg shells and bone, and similar stone in pulverized form is fed to stock, especially cows, to provide the calcium which is an important constituent of milk and bones. The Divine limestone would serve admirably for this pur- pose. Poultry grit is produced in Illinois but no figures are available as to its value. The average price for the grit produced in the United States is $6.40 per ton; mineral food averaged $3.80 per ton (Table 5). Mineral Filler Pulverized limestone is used as a mineral filler for various products, especially for asphalt. A considerable amount of white limestone is used for this purpose. Because it is stained buff or pink by a small amount of iron oxide, the Divine stone as observed in outcrops would not produce a pure white filler but would otherwise be satisfactory. The average price of lime- stone asphalt filler in 1929 was $3.37 per ton (Table 5). 24 USES OF DIVINE LIMESTONE Limestone for Rock Dusting in Coal Mines Dusty coal mines arc often sprinkled liberally with limestone dust in order to mix a non-inflammable material with the coal dust, thereby reducing the likelihood of coal-dust explosions. Limestone dust low in silica is used extensively for this purpose. The average price per ton in 1929 was $3.51 (Table 5, p. 15). The Divine limestone seems admirably suitable for tins purpose. Aluminum Refining Limestone containing more than 97 per cent calcium carbonate and not more than 1 per cent silica is used in aluminum refining. The calcium car- bonate content of the Divine limestone as tested is slightly below the requisite 97 per cent, but analysis of an unweathered sample may show that the stone meets the requirement. The silica content of the Divine stone is less than the permissible 1 per cent. Stucco, Terrazzo, and Artificial Stone Chips of crystalline limestone are often used for stucco and terrazzo and in making artificial stone. The Divine limestone will yield pinkish or brown- ish white chips, and by making selections when stripping the stone, brown and pink chips also can probably be produced from the weathered portions of the deposit. Limestone chips for stucco, terrazzo, and artificial stone sold at an average price of $3.42 in 1929 (Table 5). Other Uses The Divine limestone would probably be suitable for any other uses of stone requiring a material high in calcium carbonate and low in impurities. The uses described below are those for which it is thought the Divine limestone may be satisfactory. However, additional data regarding the char- acter and composition of the limestone are needed to determine its suitability for these purposes. Building Stone The Divine limestone is probably of value as building and decorative stone inasmuch as it takes a good polish and is available in several pleasing colors and textures. Three major varieties of stone were noted — cream toned, brown, and red. A well known cut-stone architect has described relatively small but typical polished specimens of these varieties as follows : "Cream-toned stone; highly crystalline, takes a good polish that brings up the color of delicate pink, yellow, and other toned crystals which are at- tractivelv distributed and relieve the monotony of the stone. WHITING SUBSTITUTE 25 "Brown stone ; takes a good polish but not as good as cream stone. Polish brings out cream white of shell fragments and other fossil material giving contrast and accentuating the general brown color. Some of the fossils are large enough to stand out individually and show traces of their original shape. "Red stone ; red of flowered distribution on a background of cream buff giving a fleuri effect generally, but locally more concentrated with the darker color predominating. Takes a good polish." The cream-toned stone is thought to be typical of the unweathered and unstained part of the Divine deposit. Blocks of this stone large enough to provide polished slabs for interior decoration can probably be obtained without great difficulty. The brown and red varieties are characteristic of the surface iron-stained portion of the deposit and thick slabs of these varieties may be somewhat difficult to obtain. It seems probable, however, that blocks 6 and 12 inches thick may be secured in some places. In general all three varieties appear to be suitable for most kinds of in- terior construction and decorative purposes. The cream-toned stone is prob- ably satisfactory for exterior use but the brown and red stone should be thoroughly tested to determine their weather resistance before they are used for exterior construction. Glass If the content of iron oxide is not too- high, the Divine limestone will probably meet the specifications for stone to be used in the manufacture of glass. A maximum of 0.1 to 0.3 per cent ferric oxide is permitted in lime- stone for glass making. The white or cream colored, unweathered Divine lime- stone may be satisfactory for this purpose but no data are available concerning the chemical composition of this part of the deposit. Limestone for glass fac- tories sold for an average of $1.51 per ton in Michigan and $1.79 in United States in 1929 (Table 5, p. 15). Whiting Substitute Whiting substitute is finely pulverized, very white limestone. All the limestone that was seen in the Divine area deviated from a pure white color and therefore would not make a white whiting. Whiting made from the cream colored or slightly pinkish stone might, however, be acceptable for some uses. Whiting substitute sold for an average of $5.00 per ton in 1929 (Table 5). 26 USES OF DIVINE LIMESTONE Riprap and Rubble The unweathered portions of the Divine deposit will probably yield stone suitable for riprap or rubble. Some of the pinkish-white coarsely crystalline stone should make an attractive rubble for certain types of masonry. The weathered surface stone is not recommended for riprap or rubble, however, because its weather resistance is thought to he relatively poor. Production sta- tistics on riprap and rubble are given in Table 5. Other Possible Uses The Divine limestone may possibly be employed for the purposes men- tioned below but probably less profitably than for uses described above. Limestone used for concrete aggregate, ballast, road metal, and filters must have a high resistance to wear and to weather and must be produced at low cost (Table 5). The sample of exposed Divine limestone that was tested had a French coefficient of wear of 5 (Table 3). The unweathered stone may have a higher coefficient, possibly exceeding 6, which is the minimum com- monly permissible for aggregate for concrete roads and for railroad ballast. Filter stone must endure conditions equivalent to severe weathering. Exploita- tion of the Divine limestone primarily for these uses is not recommended because the principal nearby markets for stone for these uses are already well supplied from high-grade, local sources and because the Divine stone is thought to be adapted for other purposes yielding a better price. The Divine limestone has a moderately high cementing value (Table 3) so that it may bond well and from that viewpoint may be satisfactory for waterbound macadam roads, but owing to its softness it would probably develop a slight dustiness. Inasmuch as there is an ample supply of gravel in the Divine region it seems unlikely that the Divine limestone will be used extensively for constructing macadam roads. CHER'S' LIBRARY BINDERS S07 3.GoodwtB UrbanB,IlL QKhBP