14. GS: "*»CIR 363 c. 3 C^lA ^Kxnjobu STATE OF ILLINOIS WILLIAM G. STRATTON, Governor DEPARTMENT OF REGISTRATION AND EDUCATION VERA M. BINKS, Director CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES •v. > Compiled by W. Arthur White J. E. Lamar DIVISION OF THE ILLINOIS STATE GEOLOGICAL SURVEY JOHN C.FRYE, Chief URBANA CIRCULAR 303 1960 ILLINOIS STATE GEOLOGICAL SURVEY 3 3051 00004 1 107 CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES Digitized by the Internet Archive in 2012 with funding from University of Illinois Urbana-Champaign http://archive.org/details/ceramictestsofil303whit CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES Compiled by W. Arthur White and J. E. Lamar ABSTRACT More than 125 ceramictests of Illinois clays and shales, com- piled from the files of the Illinois State Geological Survey, are pre- sented to make available information regarding the ceramic properties of a wide variety of clays and shales in 59 counties. INTRODUCTION In past years a number of clay and shale samples have been collected by members of the Illinois State Geological Survey in connection with various investi- gations for which it has not been feasible to publish reports. Detailed ceramic tests were made on many of the samples and have been available for reference at the Survey offices. Many of the samples were taken from areas for which no pub- lished ceramic data exist or from materials on which no ceramic tests had been pub- lished. For this reason, and in order that the data may be more conveniently ac- cessible, they are here compiled, together with brief notes concerning the deposits sampled . Some of the samples came from commercial deposits being worked at the time, others were taken because they constituted potential resources in certain areas, and still other samples are clays of unusual appearance or mode of occur- rence. It is believed that those parts of commercially operated deposits which were sampled have long since been removed; such tests, therefore, do not neces- sarily duplicate materials currently produced from the deposits. Nevertheless, they represent the clay or shale of a given geological formation or a rock unit and hence suggest what may be expected of other deposits of the same unit. The sample prefix letter or letters indicate who collected the samples: NF samples - J. E. Lamar and H. B. Willman; W samples - H. B. Willman; R samples - T. B. Root. Others who sampled deposits or described them are R. M. Grogan, A. H. Bell, W. C. Krumbein, and H. R. Wanless . Samples identified by number only were collected by W. A. White and W. E. Parham. The stratigraphic names of the various strata sampled have been provided by H. B. Willman and J. A. Simon. CERAMIC TESTS The detailed tests given herein were made for the Illinois State Geological Survey by members of the Department of Ceramic Engineering of the University of Illinois. The late Professor C. W. Parmelee made many of the tests, a lesser [3] 4 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 302 number were made by the late Professor R. K. Hursh and by Professor C. G. Harman. The less detailed tests which follow were made by Survey personnel. Ceramic tests of Illinois clays and shales appear in a number of other avail- able Survey publications, especially the following: Paving brick and paving-brick clays of Illinois: C. W. Rolfe, A. N. Talbot, R. C. Purdy, and I. O. Baker. Bulletin 9, 1909. Further investigations of Illinois fireclays: C. W. Parmelee and C. R. Schroyer. Bulletin 38D, 1921. Geology and mineral resources of the Marseilles, Ottawa, and Strea- tor Quadrangles: H. B. Willman and J. N. Payne. Bulletin 66, 1942. Geology and mineral resources of the Carlinville Quadrangle: J. R. Ball. Bulletin 77, 1952. Tests on clay materials available in Illinois coal mines: R. T. Stull and R. K. Hursh. Mining Investigations Bulletin 18, 1917. Refractory clays in Calhoun and Pike Counties, Illinois: J. E. Lamar. Report of Investigations 22, 1931. Clay and shale resources of extreme southern Illinois: J. E. Lamar. Report of Investigations 128, 1948. Light-burning clay resources in LaSalle County, Illinois: W. E. Parham. Circular 277, 1959. Still other tests appear in the Survey's Report of Investigations 72, "Petro- graphic and ceramic properties of Pennsylvanian shales of Illinois, " by Ralph E. Grim. This report is out of print but also appears in the Journal of the American Ceramic Society, vol. 24, no. 1, p. 23-28, 1941, where it may be consulted. DISTRIBUTION AND DESCRIPTION OF SAMPLES Figure 1 shows the distribution of samples and indicates whether the samples are surface clays, clays of Cretaceous age, clays or shales of Pennsylvanian age, or shales or clays older than Pennsylvanian age or of uncertain age. The following descriptions of samples and tests are arranged by counties. CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES KEY O Glacial clays • Pennsylvaman shales and clays A Pre-Pennsylvanian shales X Cretaceous clays Fig. 1 - Locations from which samples of clays and shales were taken for ceramic tests. 23 Workabi] .ity: good 3.64 1832°F 1922°F 2012°F 20.09 2.61 6.78 5.73 6.25 10.42 Buff Dark buff Brownish tan 6 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 ALEXANDER COUNTY SAMPLE 1423 NWi NWi sec. 21 1 T. 15 S. , R. 3 W. Illinois Minerals Company pit about Tg- miles south of Thebes along east Mississippi River bluff east of Missouri Pacific Railroad, back of farm house. About 6 to 8 feet of blue-gray clay exposed; thickness of the overburden may range from to 30 feet. Material: clay Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: firing temperature 1900°F to over 2000°F Suggested uses: structural clay products, drain tile, pottery, and flower pots. SAMPLE 1424 SEi SEi sec. 28, T. 15 S. , R. 3 W. About 1 mile north of Fayville. In north cut bank of ravine in east bluff of Mississippi River about one-eighth mile east of Missouri Pacific Railroad. The hollow contains remains of an old abandoned powder plant. About 20 feet of dark gray, well laminated shale is exposed with about 40 feet of Eocene clays and sand and Pleistocene loess as overburden. Material: shale Age: Silurian - Orchard Creek Shale Water of plasticity, percent 19 Workability: good Linear drying shrinkage, percent 3.12 Fired temperatures 1832°F Linear fired shrinkage, percent 3.12 Total linear shrinkage, percent 6.25 Fired colors Salmon Remarks: overfired at 2012°F. Firing range is probably from 1850° to about 1950°F Suggested uses: structural clay products, drain tile, and flower pots. BOND COUNTY SAMPLE 1415 NEi NWi sec. 13, T. 6 N. , R. 5 W. Richards Brick Company pit about 3 miles east of New Douglas, south side of blacktop road. Four feet of weathered Illinoian till as overburden. Material: shale Age: Pennsylvanian - Bond Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: firing range long Suggested uses: structural clay products, drain tile, and flower pots. 1922°F 2012°F 3.65 3.13 6.77 6.25 Red Red 24 Workabil ity: good 3.64 1832°F 1922°F 2012°F 5.21 5.21 7.35 8.85 8.85 10.99 Sa lmon Salmon Red 9 2.34 Workabi] .ity: good 1832°F 4.95 7.29 Salmon 1922°F 8.64 10.98 Red 2012°F 6.51 8.85 Red CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 7 BROWN COUNTY SAMPLE 1337 A SEi SEt NW£ sec. 24, T. 1 S. , R. 4 W. North shale pit of Frederic Brick and Tile Company, north of gravel road in west cut bank of Dry Fork Creek. Bottom 10 feet of face sampled, blue-gray shale. Material: shale Age: Pennsylvanian - Carbondale Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: some bloating at 2012°F Suggested uses: structural clay products, drain tile, and flower pots. SAMPLE 1351 SWi SWi NEj sec. 8, T. 1 S. , R. 3 W. About one-fourth mile north of Mt. Sterling on east side of Illinois Highway 99 on south cut bank of stream east of highway fence. Five feet of underclay underlying a thin limestone. Material: underclay Age: Pennsylvanian - Carbondale Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and flower pots. BUREAU COUNTY SAMPLE NF 256 NEi NWi NWi sec. 34, T. 17 N., R. 8 E. Sampled 1934. Strata exposed in gravel pit : ft . 3. Clay, silty (loess) (sample NF 256) 11 2. Gravel 7-10 1. Sand, pebbly 3-7 Covered Age: Pleistocene - Wisconsinan - Richland loess Characteristics of Unfired Material Color: yellow Working properties: fair - a little short Hardness: very friable Drying shrinkage, percent: linear 5.7 Reaction for carbonates: cold - trace volume 18.2 hot - trace Drying conduct: poor - tends to crack Reaction for pyrite: negative Screen test: residue on 35-mesh screen - 0.32 percent; mainly rounded quartz grains; some roots, limonite, and granite pebbles 8 Workabil ity: good 4.68 1832°F 1922°F 2012°F 1.05 2.09 3.13 5.73 6.77 7.81 Salmon Salmon Red ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 BUREAU COUNTY- continued SAMPLE NF 256 - continued Characteristics of Fired Material Absorp- Por- Burning tion % osity % Color Hard- ness shrir ikage % Cone Linear Volume Remarks 06 18.1 31.7 Salmon O 1 - ^2 0.0 0.0 Slightly scummed 1 13.5 25.0 Red 6 2.6 7.5 Slightly scummed 3 8.0 16.5 Red 7 5.5 16.5 6 3.0 2.0 Chocols ite 9 4.8 13.7 Overf ired Oxidation conduct: easily oxidized Soluble salts: sulfates present Warpage: none Suggested uses: face or common brick. CALHOUN COUNTY SAMPLE R 104 West-central part, SWi SE^ sec. 3, T. 9 S. , R. 2 W. Sampled 1930. Eleven feet of lower part of the Hannibal Shale. Age: Mississippian , Characteristics of Unfired Material A hard shale of a blue and black color 22.2 percent water to bring it to a suitabl dium-soft consistency and a "mealy" feel th content is increased or decreased. A value modulus of rupture indicates a medium bondi When slaked and washed through a 40-me sists of unslaked material that is high in black iron-containing mineral. The plastic material dries rapidly in and shows a shrinkage of 5.8 percent. The raw material reacts freely with co effervescence that indicates the presence o having a stony fracture which requires e working condition. It then has a me- at changes rather rapidly as the water of 241 pounds per square inch for the ng strength. sh sieve, the 67.5 percent residue con- siliceous particles, pyrites, and a the open air without apparent defects Id hydrochloric acid, giving a lively f carbonates. Characteristics of Fired Material Por- osity Linear shrinkage % Cone % Color Hardness Burning Total 05 22.2 Red-brown Steel hard 2.7 8.5 02 12.0 Red -brown Steel hard 4.5 10.3 1 0.6 Red-brown Steel hard 1.6 4.2 2 2.6 Red-brown Steel hard 1.2 7.0 3 0.8 Chocolate Steel hard 4.8 1.0 Oxidation conduct is only fair. The porosities and shrinkages indicate overburning after cone 1. The color is unattractive and the surface texture is rough. Suggested uses: common brick, hollow ware. 19 Workabil ityj good 3.99 1832°F 1922°F 1.74 2.26 5.73 6.25 Salmon Salmon CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 9 CALHOUN COUNTY- continued SAMPLE 1349 A NEi NEi NEi sec. 11, T. 9 S. , R. 3 W. Southwest of Illinois Highway 96, southwest cut bank of tributary to Fox Creek, behind farm buildings, about 5 miles west of Kampsville. Lower 15 feet of blue-gray shale. Material: shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 1.74 2.26 Bloated Total linear shrinkage, percent Fired colors Remarks: short firing range Suggested uses: structural clay products, drain tile, and flower pots. SAMPLE 1352 A SWi NEi SWi sec. 17, T. 11 S., R. 2 W. About 5 miles north of Batchtown on west side of road in east bluff of Mississippi River Valley. The sample represents the middle 20 feet of blue-gray, thinly laminated shale. Material: shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 6.60 7.17 Bloated Total linear shrinkage, percent Fired colors Remarks: firing range short Suggested uses: structural clay products, drain tile, and flower pots. CASS COUNTY SAMPLE R 510 SWi SWi NEi sec. 11, T. 18 N. , R. 11 W. Outcrop back of Cottonwood School, Sampled 1932. Sample from 5 feet of gray, soft shale containing" scattered ironstone con- cretions. Age: Pennsylvanian - Carbondale Formation - Francis Creek Shale Characteristics of Unfired Material Reaction for carbonates: none Reaction for pyrites: none Color: light gray Hardness: scratched with fingernail Working property: works well and has Water of plasticity, percent: 31.3 good plasticity Number of briquets: 12 Modulus of rupture: 242 lbs. per sq. in. Fineness Residue on 48-mesh : 1 percent was slaked by rubbing Character of residue: clay-bonded quartz 23 Workabil ity: good 3.82 1832°F 1922°F 6.60 7.17 10.42 10.99 Red Red 10 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 CASS COUNTY- continued SAMPLE R 510 - continued Drying Air shrinkage, plastic basis, percent: 6.3 Dry basis, percent: linear 8.3 volume 22.8 Cone Characteristics of Fired Material Absorption Color Hardness Linear shrinkage % Burning Total 010 07 01 3 19.6 12.6 0.28 0.28 Salmon-buff Salmon Brown Brown Steel hard 0.2 4.2 12.4 11.6 8.5 12.5 20.7 19.9 Remarks Drying shrinkage: medium (plastic basis) Flexural strength: medium Burning shrinkage: high-medium Color range: 0. K. Plasticity: good Vitrification: practically zero from cone 01 to cone 3 Suggested uses: sewer, common, hollow, face, glazed, enameled brick; fireproof ing; quarry, roofing, encaustic, floor, faience, and tesseral tile; drain tile and pottery not salt-glazed. CHRISTIAN COUNTY SAMPLE 1428 SEy NE-j sec. 23, T. 11 N. , R. 1 E. About Tg- miles south of Pana in north cut bank of ravine about 100 yards west of U. S. Highway 51. About 8 feet of weathered gray shale is exposed. Material: shale Age: Pennsylvanian - Mattoon Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and flower pots. 20 Workabil ity: fair 2.08 1832°F 1922°F 1.56 1.56 3.64 3.64 Salmon Salmon 2012°F 7.82 9.90 Red CLARK COUNTY SAMPLE 1345 NEi NEi SWi sec. 16, T. 11 N. , R. 11 W. About 2§- miles east of Marshall and about 1 mile south of Livingston in southwest cut bank of Big Creek. About 15 feet of dark gray, well laminated shale exposed. Material : shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Age: Pennsylvanian - Bond Formation 2012°F 6.95 8.85 Red 18 Workabil ity: good 1.90 1832°F 1922°F 1.75 4.35 3.65 6.25 Salmon Salmon 3 Workabil ity: good 2.60 1832°F 1922°F 2012°F 2.61 4.17 8.34 5.21 6.77 10.94 Salmon Salmon Red CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 11 CLARK COUNTY- continued SAMPLE 1345 - continued Remarks: high organic content in shale may be difficult to oxidize Suggested uses: structural clay products and drain tile. CLAY COUNTY SAMPLE 1420 SE^- NW? sec. 19, T. 4 N., R. 6 E. About 3j miles west of Louisville, in road ditch west of farm house. Brownish gray shale with one-fourth inch laminae, thin overburden; 3 feet exposed; topography fairly flat. Material: shale Age: Pennsylvanian - Mattoon Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and flower pots. SAMPLE B 18 Roadcut SE corner SWi NE^ sec. 35, T. 5 N., R. 6 E. Sampled 1937. Age: Pleistocene - Illinoian. Exposure consists of: ft. in. 5. Soil 6 4. Silt, hard, brown or gray 1 3. Clay (gumbotil?), gray and brown (sample B 18) 3 6 2. Gumbo sand, brown 1 6 1. Silt, gray, slightly calcareous 1 Covered Characteristics of Unfired Material Color: gray and brown Reaction for pyrite: none Hardness: readily crumbled with the fingers Soluble salts: sulfates present Fracture: irregular Reaction for carbonates: none Water of plasticity, percent: 32.2; shrinkage water, percent: 18.8; pore water, percent: 13.4 Slaking time: 100 percent clay, 17^- min'utes; 50 percent clay — 50 percent flint, 4 minutes Drying conduct: tendency to crack in drying, apparently caused by the high shrink- age characteristics of one of the clay minerals present. The clay, however, could be dried commercially without too much trouble. Scum can be noted on the drying ware but not on the fired pieces. Working properties: fair. The clay is coarse and sandy, but contains sufficient quantities of a highly plastic clay mineral to render the sample sticky and glue- like. Can be extruded with success. Drying shrinkage, percent: linear 10.7; volume 35.7 Modulus of rupture: dry clay - 990 lbs. per sq. in. - 15 specimens; with 50 percent standard sand - 250 lbs. per sq. in. - 13 specimens 12 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 CLAY COUNTY- continued SAMPLE B 18 - continued Screen test : Residue on Percent Character of residue 10-mesh 20-mesh 35-mesh 65-mesh 100-mesh 150-mesh 200-mesh 2.15 1.10 3.95 10.15 4.22 2.12 2.61 90 percent quartz (clear, brown, white, rose), somewhat rounded; limonite, about 8 percent; remainder, roots and chert About the same as on 10-mesh 95 percent quartz grains, mostly clear; few chert fragments; some roots and about 2 or 3 percent limonite; resi- due resembles river sand Mostly clear quartz grains; some limonite Same as on 35-mesh Same as on 35-mesh Same as on 35-mesh, including a. trace of hematite Characteristics of Fired Material Absorp- Por- Burning Tc tal tion % osity % Color Hard- ness shrin kage % shrir kaqe % Cone Linear Volume Linear Volume Oil 14.2 26.6 Light red 6 0.07 0.2 10.5 35.5 06 13.6 26.0 Light red 6 0.5 1.4 11.2 37.1 02 10.6 22.9 Red 6 1.9 5.7 12.6 41.4 2 11.0 26.0 Fine red 6 2.0 5.9 12.7 41.6 4 11.8 23.3 Fine red 7 2.0 5.9 12.7 41.6 7 8.0 16.4 Chocolate 8 2.9 8.5 13.6 45.6 8i 5.1 10.8 Chocolate 8 3.9 11.3 14.6 48.4 Oxidation conduct: very easy to oxidize Remarks: bends uniformly PCE value (fusion test): cone 15 Warpage: none Remarks: the clay has high drying shrinkage; the firing shrinkage is uncommonly low, and it can be matured over a wide temperature range. The color of the fired clay is especially noteworthy, being a very fine brilliant red. Suggested uses: this clay could be used for the manufacture of face brick. The fine red color and the excellent adhesive qualities suggest that the clay may have potential value as a coating to apply to face brick to produce a good red color. The texture, as well as the color, is unusual, being almost devoid of gloss. CLINTON COUNTY SAMPLE 1414 SW?- sec. 1 , T. 1 N. , R. 1 W. About 1-g- miles northwest of Centralia in south cut bank of Crooked Creek east of bridge. Eight feet of shale on limestone; overlain by sand and gravel. Material : shale Water of plasticity, percent 20 Linear drying shrinkage, percent 2.08 Age: Pennsylvanian Workability: good Bond Formation CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 13 CLINTON COUNTY- continued SAMPLE 1414 - continued Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and flower pots. 1832°F 1922°F 2012°F 4.17 4.17 8.32 6.25 6.25 10.42 Salmon Salmon Red COOK COUNTY* SAMPLE NF 238 SEi SE^ SWi sec. 28, T. 35 N., R. 14 E. Sampled 1934. Wisconsinan - Tinley till. Age: Pleistocene - Strata exposed are: 3. Soil 2. Till, brown 1. Till, gray and brown (sample NF 238) Covered ft. 12 18 in. 6 Characteristics of Unfired Material Material: till Reaction for carbonates: yes Soluble salts: sulfates present Working properties: very good Color: gray Reaction for pyrites: present Friability: crushable between fingers with reasonable force Water of plasticity, percent: 28.1; shrinkage water, percent: percent: 14 Slaking time: 100 percent clay, 11 minutes, 20 seconds; 50 percent clay cent flint, 16 minutes Modulus of rupture, dry clay: 714 lbs. per sq. in. - 12 specimens Drying shrinkage, percent: linear 8.2; volume 26.6 Drying conduct: satisfactory; easily dried Screen test : 14. 1 ; pore water, 50 per- Residue on Percent Character of residue 10-mesh 20-mesh 35-mesh 65-mesh 100-mesh 150-mesh 200-mesh 1.20 0.93 0.90 1.00 1.10 0.06 0.00 Mostly sandstone and limestone; pyrite in minor amounts Mostly sandstone and limestone; pyrite in minor amounts Mainly limestone and quartz; some pyrite Same as 35-mesh Limestone, calcite, and quartz Quartz and limestone; some siderite Characteristics of Fired Material Cone Absorp- tion % Por- osity Color Hard- ness Burning shrinkage % Total shrinkage % Linear Volume Linear Volume 011 06 02 21.2 22.2 19.5 36.5 37.1 33.7 Flesh Peach Pink 4 4 + 6 1.2 1.2 4.2 3.5 3.4 12.1 9.4 9.4 12.4 30.1 29.0 38.7 *Also sample NF 230, p. 71. 14 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 COOK COUNTY- continued SAMPLE NF 238 - continued Characteristics of Fired Material - continued Absorp- Por- Bur ning Tc >tal tion % osity % Color Hard- ness shrin kaqe % shrir ikaqe % Cone Linear Volume Linear Volume 1 11.8 24.3 Reddish brown 7-8 8.8 24.1 17.0 50.7 2 7.2 15.4 Reddish brown 8-9 8.9 24.5 17.1 51.1 4 0.00 - Chocolate 9 13.6 35.6 21.8 62.2 5 Melts Remarks: at cones 011 and 06 specimens were slightly scummed and had lime pops. At cone 02 the specimens were slightly scummed with light spots. At cones 1, 2, and 4 the specimens were spotted with light buff. Oxidation conduct: easily oxidized PCE (fusion test): cone 5; cones of this clay did not bend; they melted and slumped suddenly Warpage: none Suggested uses: common brick or drain tile. It cannot be vitrified commercially owing to its lack of vitrification range. SAMPLE NF 232 SWi NEi NW5- sec. 30, T. 36 N. , R. 15 E. Sampled in 1934. Wisconsinan ft. 2 6 12 20 Material: glacial till Age: Pleistocene Exposure in pit of Illinois Brick Company at Bernice: 4. Soil and leached glacial till 3. Till (Park Ridge), yellow-gray and brown mottled 2. Silt, gray and yellow 1. Till (Tinley), gray, practically pebble free, locally thin silt bands (sample NF 232) Covered Characteristics of Unfired Material Reaction for carbonates: yes Reaction for pyrites: present Color: gray Soluble salts: sulfates present Friability: crushable between fingers Working properties: very good Water of plasticity, percent: 22.2; shrinkage water, percent: 9.0; pore water, percent: 13.2 Slaking time: 100 percent clay, 10 minutes; 50 percent clay— 50 percent flint, 40 minutes Drying shrinkage, percent: linear 5.76; volume 18.3 Drying conduct: satisfactory; easy to dry Modulus of rupture: Lbs, per sq. in. No. of specimens Dry clay With 50 percent standard sand 390 201 7 13 Screen test: Residue on Percent Character of residue 10-mesh 3.45 Limestone and sandstone in about equal portions; about 25 percent of the residue is fragments of a black ferro- magnesian rock; a few fragments of pyrite are present CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 15 COOK COUNTY- continued SAMPLE NF 232 - continued Screen test - continued Residue on Percent Character of residue 20-mesh 1.46 3b-mesh 2.01 Same as 10-mesh 65-mesh 2.50 Sandstone, limestone, and quartz 100-mesh 1.15 Sandstone, limestone, and quartz 150-mesh 1.15 Sandstone, limestone, and quartz 200-mesh 1.27 Sandstone, limestone, and quartz Characteri sties o: f Fired Material Absorp- Por - Burning Total tion osity Hard' shrinkage % shrinkage % Cone % % Color ness Linear Volume Linear Volume Oil 06 02 2 2i 20.1 19.7 18.5 9.9 8.1 0.6 Melts 34.5 33.4 32.1 19.8 16.5 1.4 Light buff Cream Light buff Dark buff Greenish buff Greenish buff 4 4 5 5-7 0.77 0.5 1.3 8.1 8.4 10.8 2.3 1.5 3.7 22.2 23.2 29.1 6.5 6.3 7.1 13.9 14.2 16.6 20.6 19.8 22.0 40.5 41.3 47.1 Remarks: the specimen at cone 2 was not uniform owing to rapid changes with tem- perature. Fired clay is speckled with cream spots caused by concentrations of limy clay or pebbles. Oxidation conduct: easily oxidized Soluble salts: sulfates present PCE value (fusion test): cone 5} cones of this clay did not bend; they melted and slumped suddenly Warpage: none Suggested uses: common brick or drain tile. It cannot be vitrified commercially owing to lack of vitrification range. SEi SEi sec. 33, T. 39 N. SAMPLE D 7 13 E. Sampled in 1932. Age Material: glacial till Exposure consists of: 3. Soil, black 2. Sand, brown, silty, calcareous 1. Till (Lake Border), dark gray (sample D 7) Covered Pleistocene ft. i£ 2 20 Characteristics of Unfired Material Wisconsinan Reaction for carbonates: yes Color: light gray, almost white Working property: sticky Number of briquets: 13 Residue on 48-mesh, percent: 8.4 Reaction for pyrites: yes Hardness: 1 on Moh's scale Water of plasticity, percent 25.4 Modulus of rupture: 450 lbs. per sq. in. Fineness Character of residue: limestone, granite, limonite, quartz, igneous rocks, etc. 010 21.9 07 20.6 01 11.8 16 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 COOK COUNTY- continued SAMPLE D 7 - continued Drying Air shrinkage, plastic basis, percent: 6.78 Dry basis, percent: linear 8.5 volume 23.4 Characteristics of Fired Material Absorption Linear shrinkage % Cone % Color Hardness Burning Total Light buff Scratched 0.1 8.6 Scratched 0.3 8.8 Greenish Steel hard 4.9 13.4 brown with white spots 2 0.3 Light brown 8.7 17.2 with white spots Remarks Drying shrinkage: medium (plastic basis) Color: variable Flexural strength: high-medium Plasticity: sticky Vitrification conduct: rapid after cone 01 Burning shrinkage: medium (cone 03) Suggested uses: limy brick, common brick, possibly hollow ware. CRAWFORD COUNTY SAMPLE 1421 SWi SWi NEi sec. 1, T. 5 N. , R. 12 E. About three-fourths mile west of Flat- rock in west bank of ravine inside fence north of bridge, west of farm house. Three feet of gray shale exposed; overburden would be thin in this area. Material: shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: ferrous sulfate scumming; this scumming would not occur in unweathered shale Suggested uses: structural clay products, drain tile, and flower pots. CUMBERLAND COUNTY SAMPLE 1353 A NEi NWt SWi sec. 36, T. 10 N., R. 9 E. About 1 mile north of Greenup in south cut bank of Bell Creek about 50 yards west of old road west of Illinois Highway 130. Ten feet of dark gray shale. Material: shale Age: Pennsylvanian - Mattoon Formation Water of plasticity, percent 21 Workability: poor Linear drying 'shrinkage, percent 1.56 18 Workabil ity: fair 1.56 1832°F 1922°F 2012°F 3.12 4.17 7.81 4.68 5.73 9.37 Salmon Salmon Red Workabil ity: fair 2.08 1832°F 1922°F 2.09 4.17 4.17 6.25 Salmon Salmon CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 17 CUMBERLAND COUNTY- continued SAMPLE 1353 A - continued Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 3.13 6.25 7.34 Total linear shrinkage, percent 4.69 7.81 9.90 Fired colors Salmon Salmon Red Remarks: shale may be difficult to oxidize owing to the organic content Suggested uses: drain tile. SAMPLE 1346 A NWi NWi SWi sec. 2, T. 9 N. , R. 9 E. Northwest corner of Greenup, roadcut along east side of Illinois Highway 121 in south bluff of Embarrass River. Lower 10 feet of shale; shale in this area ranges from 30 to 40 feet thick. Material: shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 2.09 4.17 4.17 Total linear shrinkage, percent 4.17 6.25 6.25 Fired colors Salmon Salmon Red Remarks: test brick bloated some at 2012°F Suggested uses: structural clay products, drain tile, and flower pots. DU PAGE COUNTY SAMPLES NF 147 and 148 S&j- NWi NEi sec. 4, T. 40 N., R. 9 E. Sampled in 1933. A concrete road crossing a peat bog in the West Chicago moraine caused a heave of peat and of the clay underlying it. Sample NF 147 was dark gray clay and NF 148 dark gray, woody clay. Age: Pleistocene - Wisconsinan. SAMPLE NF 147 Characteristics of Unfired Material Material: clay taken from below a peat bed Reaction for carbonates: negative Color: dark gray, uniform Hardness: medium; finely granular Working property: fair; short and tends fracture to tear rather easily Fineness Residue, percent: 35-mesh - 0.12 Character of residue: vegetable matter Drying Air shrinkage, percent: linear 14.4 Drying conduct: satisfactory volume 49.6 Scumming: slight Characteristics of Fired Material Cone Absorption % Color Hardness 06 38.3 Light salmon 3 02 9.4 Red 6 4 1.8 Deep maroon 8 18 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 DU PAGE COUNTY- continued SAMPLE NF 147 - continued Remarks: at cone 4, the sample oxidized, reduced, re-oxidized; very great shrinkage Suggested uses: it may be useful for common brick, but is difficult to form and has excessive burning shrinkage. SAMPLE NF 148 Characteristics of Unfired Material Material: clay taken from beneath a peat bed Reaction for carbonates: negative Color: dark gray, uniform Working properties: slightly dif- Hardness: medium; granular fracture ficult to temper; too short to attempt any wedging Fineness Residue, percent: 35-mesh —■ after several Character of residue: mineral days' agitation, 11 percent still unslaked impurities are not suspected Drying Air shrinkage, percent: linear 11.0 Drying conduct: satisfactory volume 36.7 Scumming: none Characteristics of Fired Material Cone Absorption % Color Hardness 06 75.0 Tan 02 27.8 Red 3 4 3.5 Maroon 8 Remarks: at cone 06, sample crumbled when handled; at cone 4, it had high shrinkage Suggested uses: not suited for ceramic purposes. EDWARDS COUNTY SAMPLE 1326 A NEi NEi sec. 11, T. 2 S. , R. 10 E. Pit of Albion Brick Company south of Albion. Twenty feet of blue-gray and buff shale exposed. Material: shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and flower pots. EFFINGHAM COUNTY SAMPLE 1416 NWi SWy sec. 1, T. 6 N., R. 5 E. About 4 miles northeast of Mason on north side of Illinois Highway 37 about 100 yards west of Illinois Central Railroad. About 4 feet of shale exposed in roadcut, and overburden would be shallow. 22 Workabil ity: good 3.64 1832°F 1922°F 2012°F 4.69 7.34 7.82 8.33 10.98 11.46 Salmon Red Red CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 19 EFFINGHAM COUNTY- continued SAMPLE 1416 - continued Material: shale Age: Pennsylvanian - Mattoon Formation Water of plasticity, percent 20 Workability: good Linear drying shrinkage, percent 3.12 Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 0.52 1.05 4.17 Total linear shrinkage, percent 3.64 4.17 7.29 Fired colors Salmon Salmon Red Remarks: scumming Suggested uses: drain tile, structural clay products if scumming could be con- trolled. FAYETTE COUNTY SAMPLE 1427 NE£ NEi sec. 28, T. 7 N. , R. 3 E. About one-fourth mile west of St. Elmo, north of Pennsylvanian Railroad and south of county road. About 20 feet of blue-gray shale which contains siderite concretions. Material : shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: overburned at 2012°F Suggested uses: structural clay products and drain tile. FULTON COUNTY SAMPLES 611 and 612 * Ravine south of Chicago, Burlington, and Quincy Railroad, NWj SE^- sec. 1, T. 4 N., R. 2 E. Sampled in 1930. Age: Pennsylvanian Carbondale Formation ft . in. 11. Sandstone 60 10. Shale 8-11 9. Coal (Colchester No. 2 Coal) 2 6 Spoon Formation 8. Underclay, gray (sample 612) 4 7. Sandstone 4 6. Shale and clay 5 5. Coal (Wiley Coal) 6 10 4. Underclay, gray (sample 611) 1 6 3. Limestone, gray 1 2. Sandstone 1 3 1. Shale, clay, and one-inch coal 11 4 Covered 8 Workabil ity: good 3.64 1832°F 1922°F 2012°F 4.69 4.69 4.69 8.33 8.33 8.33 Salmon Salmon Red * Wanless, H. R., Geology and mineral resources of the Havana Quadrangle: Illinois Geol. Survey unpub. ms. HRW-4, 1930. 20 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 FULTON COUNTY SAMPLE 611 continued Characteristics of Unfired Material Material : clay Drying conduct: good Drying shrinkage, percent Screen test: Residue on 28-mesh 48-mesh 65-mesh 100-mesh 200-mesh linear 7.80 volume 21.85 Water of plasticity, percent: 29.1 Bulk specific gravity: 1.84 Bonding strength: modulus of rupture, 233.80 lbs. per sq. in. Percent 23. ,9 10, ,4 2, ,5 4, ,9 16. .4 Characteristics of Fired Material Burning shrinkage % Cone Porosity % Color Fracture Linear Volume 05 27.44 Salmon Granular 4.54 13.02 02 20.93 Salmon-buff Granular 5.08 14.47 2 19.97 Light buff Granular 5.31 15.09 5 11.54 Pinkish buff Granular 7.01 19.59 7 7.55 Light tan Granular 7.84 23.35 10 11 9.56 7.64 Buff with black spots Granular 7.74 Bl oated 21.49 Fusion test: clay not refractory Oxidizing conduct: poor Remarks: drying shrinkage medium; bonding strength medium; vitrification complete between cone 7 and 10; overburned at cone 10; burning shrinkage at vitrification medium-low. It is not refractory. Suggested uses: drain tile, hollow ware, etc. SAMPLE 612 Characteristics of Unfired Material Material: clay Water of plasticity, percent: 24.3 Drying conduct: good Bulk specific gravity: 1.90 Drying shrinkage, percent: linear 6.58 Bonding strength: modulus of rupture, volume 18.45 363.54 lbs. per sq. in. Characteristics of Fired Material Burning shrinkage % Cone 05 02 2 5 6 rosity % Color Fracture Linear Volume 15.92 Light buff Smooth 5.75 16.27 9.49 Light buff Smooth 7.215 20.12 1.28 Light tan Smooth 7.854 21.76 3.40 Overburned Smooth Bl oated 16.05 Bl oated CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 21 FULTON COUNTY- continued SAMPLE 612 - continued Fusion test: clay not refractory Oxidizing conduct: good Remarks: drying shrinkage medium; bonding strength medium; vitrification com- plete at cone 2; overburned at cone 2; burning shrinkage at vitrification medium-low; nonrefractory clay Suggested uses: building brick, possibly drain tile, hollow tile, etc. SAMPLES 610 and 613* NW5- SEi sec. 30, T. 4 N., R. 3 E. Lower part of ravine west of highway. Sampled in 1930. Age: Pennsylvanian - Spoon Formation Lower part of exposure is: ft. in. 4. Shale or clay, gray (sample 613) 4 6 3. Shale, dark gray 2 2. Coal li 1. Underclay, gray, with blocky fracture 3 (sample 610) SAMPLE 610 Characteristics of Unfired Material Material: clay Water of plasticity, percent: 23.22 Drying conduct: good Bulk specific gravity: 1.97 Drying shrinkage, percent: linear 6.63 Bonding strength: modulus of rupture, volume 18.22 282.8 lbs. per sq. in. Screen test : Residue on Percent 28-mesh 3.7 48-mesh 28.3 65-mesh 7.6 100-mesh 5.4 200-mesh 24.1 Characteristics of Fired Material Burning shrinkage % Cone Porosity % Color Fracture Linear Volume 04 26.25 Cream Granular 2.14 6.19 02 21.57 Cream Granular 4.37 12.55 2 21.47 Cream Granular 6.60 10.42 3 16.99 Light tan Granular 5.31 15.10 6 9.80 Tan Granular 6.65 18.64 8 10.20 Bluestoned Granular 6.86 19.20 PCE value (fi jsion test ) : cone 27-28 Oxidizing conduct : poor Remarks : dr' /ing shrinka< je medium; bondin< 3 strength medium; vitrification incom- plete at cone 8j shrinkage at cone 8 medium-low; clay is refractory Suggested uses: building brick, possibly quarry tile, roofing tile, flue lining, sanitary ware, and stove linings. * Wanless, H. R., Geology and mineral resources of the Havana Quadranglet Illinois Geol. Survey unpub. ms. HRW-4, 1930. 22 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 FULTON COUNTY- continued SAMPLE 613 Characteristics of Unfired Material Material: clay Drying conduct: good Drying shrinkage, percent; linear volume Water of plasticity, percent: 24.10 Bulk specific gravity: 1.91 11.55 Bonding strength: modulus of rupture, 30.90 248.5 lbs. per sq. in. Characteristics of Fired Material Burning shrinkage % Cone Porosity % Color Fracture Linear Volume 05 20.11 Tan Granular 3.80 10.97 02 11.86 Dark tan Granular 6.42 18.05 2 14.68 Dark tan Granular 6.34 17.83 4 5.71 Bl oated 7 15.37 Bl oated Fusion test: clay not refractory Oxidizing conduct: poor Remarks: drying shrinkage medium-high; bonding strength, medium; vitrification overburns suddenly between cones 2 and 4; shrinkage at cone 2 medium-low; non- refractory Suggested uses: building brick and possibly hollow tile. SAMPLE R 215 SE^r SE-5- NW5- sec. 7, T. 5 N. , R. 5 E. Outcrop in the ravine west of road. Sampled in 1931. Sample from 7 feet, 9 inches of gray-blue shale with scattered small iron- stone concretions. Age: Pennsylvanian - Carbondale Formation - Canton Shale. Characteristics of Unfired Material The material is a hard, sandy shale that is uniformly gray in color, has a stony fracture, poor plasticity over a short range, and requires 23.9 percent water to develop its normal, moderately soft, working consistency. A low-medium bonding strength is indicated by a value of 165 pounds per square inch for the modulus of rupture. The material dries fairly rapidly under ordinary atmospheric conditions with- out difficulty, scums slightly, and has a shrinkage of 4.9 percent. When slaked and washed on a 40-mesh sieve, 10.1 percent residue remains; the unslaked original material contains considerable mica and some pyrites. Treatment with hot and cold hydrochloric acid causes mild evolution of gas, indicating the presence of carbonates. When burned, the clay oxidizes readily and has the vitrification characteris- tics indicated below. Characteristics of Fired Material Linear shrinkage % Cone Porosity % Color Hardness Burning Total 04 26.0 Light red 3.4 18.3 01 15.2 Light red 6.7 11.6 1 13.8 Light red Steel hard 7.3 12.2 3 7.8 Dark red Steel hard 8.6 13.5 6 2.4 Gunmetal Steel hard 4.1 9.0 1832°F 1922°F 2012°F 3.13 5.21 8.34 5.21 7.29 10.42 Salmon Salmon Red CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 23 FULTON COUNTY- continued SAMPLE R 215 - continued Remarks: this material vitrifies rapidly and reaches a minimum porosity between cone 3 and cone 6. At the latter temperature, it seems slightly overburned. The total shrinkages change little and are high-medium. Suggested uses: common and face brick, hollow ware. Some traces of soluble salts were noted, which will have an important influence upon the product. SAMPLE 1322 A Sec. 7, T. 5 N.j R. 5 E. Pine Ridge Coal Company pit. The sample was taken from a bin at Peoria Brick and Tile Company. Material: shale Age: Pennsylvanian - Carbondale Formation Water of plasticity, percent 17 Workability: fair Linear drying shrinkage, percent 2.08 Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and flower pots. SAMPLES V 1 - 4 SE-j sec. 22, T. 6 N., R. 1 E. Railroad cut and ravine. Sampled about 1939. (Section from Wanless, H. R., 1957, Geology and mineral resources of the Beardstown, Glasford, Havana and Vermont quadrangles: Illinois Geol. Survey Bull. 82, p. 201.) ft. in. Pennsylvanian Spoon Formation 7. Underclay, light gray (sample VI) 1 below Seahorne Limestone 6. Shale, carbonaceous 3 5. Underclay, light brownish gray (sample V 2) 1 6 4. Shale, dark blue-gray 6 3. Clay, coaly 1 2. Underclay, light gray (sample V 3) 5 1. Shale, light gray (sample V 4) 4 SAMPLE V 1 Characteristics of Unfired Material Color: light yellow Working properties: fair - a little Hardness: crumbled between fingers too sticky with difficulty Drying shrinkage, percent: linear 9.7 Fracture: granular volume 32.0 Reaction for carbonates: cold - negative Drying conduct: requires some care in hot - trace drying Screen test: residue on 35-mesh screen - 2.4 percent; mainly gypsum; some limon- ite and some root casts 24 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 FULTON COUNTY continued SAMPLE V 1 - continued Characteristics of Fired Material Absorp- Por- Burning tion osity % Color Hard- ness shrir ikaqe % Cone % Linear Volume Remarks 06 14.2 27.9 Orange- buff 4 3.5 10.0 Slightly scummed 2 2.5 5.0 Tan 8 9.1 24.8 Slightly scummed, cream colored specks 6 0.15 0.3 Light brown 9 9.4 25.6 Slightly scummed, cream colored specks Oxidizing conduct: requires somewhat lengthened oxic lation period Soluble salts: considera ble PCE value ( fusion te st): cone 18 Suggested uses : this material could possibly be used as a bond clay for certain refractory materials, if used in small amounts. It could be used for common brick and face brick if the scumming could be overcome. SAMPLE V 2 Characteristics of Unfired Material Color: light gray, flecked with dark gray and yellow Hardness: shattered between the fingers with difficulty Fracture: granular Reaction for carbonates: cold - trace hot - trace Screen test: residue on 35-mesh screen - 1.1 percent; 50 percent is gypsum; most of the remainder is sandstone, with some coal and limonite Characteristics of Fired Material Soluble salts: plentiful Working properties: fair, rather too plastic Drying shrinkage, percent: linear 8.1 volume 26.2 Drying conduct: must be dried slowly Absorp- Por- Burning tion % osity % Color Hard- ness shrir ikage % Cone Linear Volume Remarks 06 12.5 25.5 Light buff 5 2.1 6.2 Slightly scummed 2 6.7 14.9 Light tan 8 5.6 16.0 Flecked with light and red specks; scum 3 11.6 Light tan 9 6.0 17.2 Same as above 6 4.5 10.2 Light tan 9 7.9 21.8 Same as above Soluble salts: present Suggested uses: face and common brick. SAMPLE V 3 Characteristics of Unfired Material Color: mixture of yellow and greenish gray clays Hardness: breaks readily into granules, some of which are very hard Fracture: granular Reaction for carbonates: cold - positive hot - trace Working properties: works well CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 25 FULTON COUNTY- continued SAMPLE V 3 - continued Drying shrinkage, percent: linear 8.5 Drying conduct: dries safely with volume 27.7 reasonable care Screen test: residue on 35-mesh screen - 0.17 percent; nearly all gypsum; some sandstone, coal, and limonite Characteristics of Fired Material Absorp- Por- Burning tion osity Hard- shrinkage % Cone % % Color ness Linear Volume Remarks 06 11.4 21.9 Light 6^ 4.6 13.1 Scumming buff 3 0.05 0.01 Tan 9 10.3 27.9 Scummed slightly 6 0.00 0.00 Tan 9 10.4 28.0 Oxidation conduct: requires some oxidation treatment to prevent bluestoning Suggested uses: if the scumming can be eliminated, the material would be suitable for buff face brick, terra cotta, stoneware, or some types of pottery. SAMPLE V 4 Characteristics of Unfired Material Color: gray Soluble salts: sulfates present Hardness: easily crushed between the Working properties: good fingers Drying shrinkage, percent: linear 7.0 Fracture: granular volume 22.4 Reaction for carbonates: cold - feeble Drying conduct: no difficulty encountered Screen test: residue on 35-mesh screen - 1.8 percent; mainly limonitic sandstone; calcite present in minor quantities; a few small roots Characteristics of Fired Material Absorp- Por- Burning tion % osity % Color Hard- ness shrir ikage % Cone Linear Volume Remarks 06 11.3 23.2 Light buff 6 3.3 9.7 Sulfate scum 2 5.1 11.5 Tan 8 7.9 21.8 Sulfate scum 6 0.1 0.2 Tan 9 9.6 26.0 Soluble salts: present Suggested uses: if the scumming can be eliminated, the clay could be used for the manufacture of face brick, terra cotta or stoneware. SAMPLE 1350 A Sec. 10, T. 6 N.j R. 3 E. Truax Traer Coal Company pit southwest of Fiatt. About 40 feet of blue-gray shale; overburden is 50 to 20 feet. Material: shale Age: Pennsylvanian - Carbondale Formation Water of plasticity, percent 18 Workability: good Linear drying shrinkage, percent 2.38 26 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 FULTON COUNTY- continued SAMPLE 1350 A - continued Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: scummed, over fired at 2012°F Suggested uses: structural clay products, drain tile, and flower pots. SAMPLE R 214 1832°F 1922°F 2012°F 3.35 5.95 4.91 5.73 8.33 7.29 lalmon Salmon Brown NEi SWi SEi sec. 31, T. 6 N. , R. 5 E. Sampled in 1931. Sample from 13 feet of gray blocky shale, with scattered clay ironstone con- cretions. Age: Pennsylvanian - Carbondale Formation - Purington Shale. Characteristics of Unfired Material The material is a hard, sandy shale that is uniformly gray in color, has a stony fracture, poor plasticity over a short range, and requires 26.3 percent water to develop its normal, quite soft, working consistency. A low-medium bonding strength is indicated by a value of 168 pounds per square inch for the modulus of rupture. It dries somewhat slowly but without difficulty under ordinary atmospheric conditions; scums slightly; and has a shrinkage of 5.1 percent. When slaked and washed on a 40-mesh sieve, 8.9 percent residue remains; it consists of unslaked original material high in mica, and contains some iron sulfide minerals. Treatment with hot hydrochloric acid causes mild evolution of gas, indicating the presence of carbonates. When burned, the clay oxidizes without difficulty and has the vitrification characteristics indicated below. Characteristics of Fired Material Linear shrinkage % Cone Porosity % Color Hardness Burning Total 04 28.8 Salmon 3.2 8.3 01 20.2 Br own -red 6.4 11.5 1 17.7 Red Steel hard 6.9 12.0 2 15.9 Red Steel hard 7.6 12.7 4 7.8 Chocolate Steel hard 9.5 14.6 6 0.4 Black Steel hard 6.4 11.5 Remarks: this material vitrifies slowly until cone 2 is reached, then more rapidly. It overburns above cone 4 but not seriously at cone 6. The total shrinkages are medium. The most favorable range for color is from cone 01 to cone 4 inclu- sive, varying from brown-red to chocolate. Suggested uses: common and face brick, if the soluble salts can be controlled; possibly paving brick and hollow ware. GREENE COUNTY SAMPLES R 113 and R 114 SWi NEi SE? sec. 15, T. 11 N. , R. 13 W. Sampled in 1930. Age: Pennsylvanian Spoon Formation. ,. 3. Clay, gray, hard (sample 113) 4 2. Clay, pink, red, and yellow 1 1. Clay, white, sandy (sample 114) 2 Covered CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 27 GREENE COUNTY- continued SAMPLE R 113 Characteristics of Unfired Material Sample R 113 is a nearly white, medium hard, rather sandy material containing small lumps of a harder, smooth clay. When 17.6 percent of water is added, it de- velops a soft consistency and a rather poor plasticity of a limited range. When this plastic material is dried, it shows a linear shrinkage of 4 percent, and it dries rapidly without defects under ordinary laboratory room conditions. It has a low-medium bonding strength with a value of 153 pounds per square inch for the modulus of rupture. When slaked and washed on a 40-mesh sieve, a residue of 77 percent is obtained, which under the magnifying glass appears to be quartz grains bonded with a white clay. When burned, no special oxidation treatment is required. Characteristics of Fired Material Cone Porosity % Color Hardness Linear shrinkage % Burning Total 05 32 White Scratched by steel 1 5 01 32 White Scratched by steel 1 5 1 30 White Scratched by steel 1 5 2 31 White Scratched by steel 1 5 3 29 White Scratched by steel 2 6 6 29 White Scratched by steel 2 6 8 29 White Scratched by steel 2 6 9 28 White Scratched by steel 2 7 11 27 White Scratched by steel 3 7 14 26 Cream Scratched by steel 3 7 Remarks: fusion test gave a PCE value of 30g-. This clay burns with little change in porosity, shrinkage, or color throughout a wide range of temperatures. Suggested uses: suited to manufacture of a variety of refractory products. SAMPLE R 114 Characteristics of Unfired Material Sample R 114 is a hard clay having a nearly white color and a stony fracture. When 19.5 percent of water is added, the mass shows a fair degree and range of plasticity. When exposed to ordinary room temperature the plastic mass dries safely with a shrinkage of 5.5 percent. It has a low bonding strength with a value of 47.5 pounds per square inch for the modulus of rupture. When slaked with water and washed through a 40-mesh sieve a residue of 8 per- cent remains. This consists chiefly of fine quartz sand grains as well as quartz grains bonded with a white material. Further screen analysis gives the following: 48-mesh - 10.7 percent; 65-mesh - 9.6 percent; 100-mesh - 12.0 percent; and through 100-mesh - 67.7 percent. The clay reacts faintly with hydrochloric acid indicating the probable pres- ence of small amounts of carbonates. When burned, the clay does not require any special oxidation treatment. Characteristics of Fired Material Cone Porosity % Color Hardness Linear shrinkage % Burning Total 05 01 28.7 28.1 White White 0.9 1.0 6.4 6.5 28 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 GREENE COUNTY- continued SAMPLE R 114 - continued Characteristics of Fired Material - continued Linear shrinkage % Cone Porosity % Color Ha rdness Burning Total 1 27.7 White 1.3 6.8 2 27.8 White 1.2 6.7 3 27.2 White 1.5 7.0 6 27.4 White 1.7 7.2 8 25.5 Cream 2.1 7.6 9 24.6 Cream 2.7 8.2 11 23.9 Tan 2.9 8.4 14 17.8 Tan St eel hard 4.2 9.7 Remarks: the clay is refractory as its PCE is between cones 29 and 30. It is an open-burning material having only a slight change of porosity over a wide tem- perature range. Its total shrinkages are very low and show only a small increase throughout a wide range of temperature. The color of the burned clay is nearly white up to cone 6, after that it develops a cream which becomes a tan. Suggested uses: manufacture of refractories, certain kinds of sanitary ware, architectural terra cotta, face brick. SAMPLES BELL 1 and 3 12 N., R. 11 W. Sampled about 1930 (A. H. Bell, NWi SEi SEi sec. 5, T. personal communication). Pleistocene ft. in. 8. Soil and till 4 7. Clay, greenish 4 Pennsylvanian - Carbondale Formation 6. Limestone, yellow, earthy 4 5. Clay, yellow and green 1 4 4. Clay, carbonaceous, dark gray 6 3. Clay, gray, nonbedded (sample Bell 3) 8 2. Limestone, with irregular nodules and druses of calcite 2 1. Shale, silty, yellowish gray, finely laminated (sample Bell l) 6 Covered SAMPLE BELL 1 Characteristics of Unfired Material The material is a shale that contains concretions, is very light tan in color, has an irregular hackly fracture, good plasticity over a satisfactory range, and requires 28.8 percent water to develop its normal, medium-soft, working consistency. A medium bonding strength is indicated by a value of 237 pounds per square inch for the modulus of rupture. It dries somewhat slowly under ordinary atmospheric conditions, with some crack- ing, and has a shrinkage of 6.8 percent. When slaked and washed on a 40-mesh sieve, 7.9 percent residue remains, which consists of some large, brown, "sandstone-like" particles, considerable quartz, some gray lumps high in mica, and a few particles which appear to be red iron crys- talline formations bonded with a gray substance. Treatment with cold hydrochloric acid causes moderate evolution of gas, indicat- ing the presence of carbonates. When burned, the clay oxidizes readily. CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 29 GREENE COUNTY- continued SAMPLE BELL 1 - continued Characteristics of Fired Material Linear shrir ikage % Cone Porosity % Color Hardness Burning Total 06 28.2 Salmon 3.7 10.5 02 19.7 Light red Steel hard 6.6 13.4 01 18.3 Light red Steel hard 6.8 13.6 2 5.8 Dark brownish red Steel hard 9.1 15.9 4 0.3 Chocolate Steel hard 9.7 16.5 6 11.6 Steel hard 3.9 10.7 Remarks: the material vitrifies rapidly and is overburned between cones 4 and 6. The rate of burning shrinkage increases rapidly between cone 01 and 2, and the total shrinkage is high. The color changes decidedly from cone 02 to cone 4. Suggested uses: hollow ware and common brick. SAMPLE BELL 3 Characteristics of Unfired Material The material is a stoneware type of clay, mottled gray and tan in color, has a hackly fracture, is slightly soapy, has very sticky plasticity over a wide range, and requires 35.8 percent water to develop its normal medium-stiff working con- sistency. A medium bonding strength is indicated by a modulus of rupture of 393 pounds per square inch. It dries slowly under ordinary atmospheric conditions without difficulty, scums slightly, and has a shrinkage of 14.0 percent. When slaked and washed on a 40-mesh sieve, 1.0 percent residue remains which consists of quartz grains, a few red stony particles, and a few larger brown frag- ments, probably limestone. Further screen analysis of the material showed 0.1 per- cent residue on 48-mesh, 1.6 percent of 65-mesh, 3.5 percent on 100-mesh, and 94.8 percent through 100-mesh. Treatment with cold hydrochloric acid causes mild evolution of gas indicating the presence of carbonates. When burned, the clay oxidizes readily. Characteristics of Fired Material Linear shrinkage % Cone Porosity % Color Hardness Burning Total 05 13.3 Pale brown to tan Steel hard 6.1 20.1 02 4.3 Pale brown to tan Steel hard 6.9 20.9 01 5.5 Pale brown to tan Steel hard 6.8 20.8 2 1.2 Pale brown to tan Steel hard 7.3 21.3 3 0.4 Pale brown to tan Steel hard 7.5 21.5 6 0.9 Bluestone Steel hard 7.4 21.4 8 0.4 Bluestone Steel hard 7.3 21.3 9 23.2 Stoneware gray Steel hard 12.2 26.2 11 21.9 Dark gray Steel hard 0.9 13.1 Remarks: the material vitrified gradually above cone 05 and has a long range as it does not overburn until cone 8 is passed. It has a PCE value of cone 18. The burning shrinkage is practically constant up to the latter cone. There are indi- cations of soluble salts present. Suggested uses: fireproofing and hollow ware; also, if soluble salts can be cor- rected, face brick, tile, architectural terra cotta, and stoneware. 30 Francis Creek Shale 4.50 Workabili ty: good 1832°F 1922°F 2012°F 6.96 7.48 4.35 11.46 11.98 8.85 Salmon Salmon Red 30 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 GREENE COUNTY- continued SAMPLE 1355 A SEi NW? sec. 30, T. 12 N., R. 11 W. Two and one-half miles northeast of Whitehall. About 15 feet of brownish yellow shale, overburden 15 to 20 feet. Material : shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: overburned at 2012°F Suggested uses: structural clay products, drain tile, sewer pipe, and flower pots. GRUNDY COUNTY SAMPLES 1331 A and 1331 F SWi SWi sec. 12, T. 31 N. , R. 8 E. East of East Brooklyn, pit of Northern Illinois Coal Corporation. Ten feet of blue-gray shale above No. 7 Coal. Material: shale Age: Pennsylvanian - Modesto Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: overburned at 2012°F Suggested uses: sewer pipe and structural clay products. SAMPLE 1331 B Same location as above. Blue-gray siltstone 5 feet, and 5 feet of blue-gray clay, calcareous, above sample 1331 A. Material: siltstone and clay Age: Pennsylvanian - Modesto Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: contains lime Suggested uses: common brick, building tile, and drain tile. SAMPLE 1331 C Same location as sample 1331 A. Five feet of underclay and shale above siltstone and clay. 26 Farmington Shale 4.42 Workabi! Lity: fair 1832°F 1922°F 2012° 6.51 8.60 7.04 10.93 13.02 11.46 Salmon Red Red !5 Workabi 1 ity: fair 6.25 1832°F 1922°F 201 2° F 0.00 1.04 1.56 6.25 7.29 7.81 Salmon Salmon Dirty red CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 31 GRUNDY COUNTY- continued SAMPLE 1331 C - continued Material: underclay and shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: overfired at 2012°F; color not desirable for face brick Suggested uses: common brick, drain tile, building tile, and sewerpipe. SAMPLE 1401 26 Workabili ty: good 6.77 1832°F 1922°F 2012°F 0.52 1.04 0.00 7.29 7.81 6.77 Red-brown Red— brown Red-brown SW5- sec. 11, T. 33 N. , R. 6 E. Morris Clay Company pit, about 4 miles west of Morris. Upper 20 feet of brownish gray, sandy shale. Material: shale Age: Pennsylvanian - Carbondale Formation - Water of plasticity, percent 16 Francis Creek Shale Linear drying shrinkage, percent 2.08 Workability: good Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 1.56 7.29 7.81 Total linear shrinkage, percent 3.64 9.37 9.89 Fired colors Salmon Salmon Red Suggested uses: structural clay products, drain tile, and flower pots. HANCOCK COUNTY SAMPLE 1408 SWi SWi sec. 26, T. 3 N. , R. 5 W. Southeast bank of Williams Creek, about 200 yards southeast of Augusta-Clayton road about 2 miles south of Augusta. About 30 feet of gray shale exposed, overburden about 30 feet. Material: shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 1.57 5.21 3.65 Total linear shrinkage, percent 4.17 7.81 6.25 Fired colors Salmon Salmon Red Remarks: scummed; overfired at 2012°F Suggested uses: drain tile, and structural clay products if soluble salts could be controlled. JACKSON COUNTY SAMPLE 1336 A NWi SWi NWi sec. 10, T. 9 S. , R. 2 W. West bank of ravine about 200 yards upstream from mine. About 16 feet medium gray to brownish gray, poorly to well bedded, silty shale, with spheroidal weathering and plant traces. 24 Format ion - Franci 2.60 Workabil ity: good 1832°F 1922°F 1.57 5.21 4.17 7.81 Salmon Salmon 9 2.08 Workabi; Lity: fair 1832°F 3.65 5.73 Salmon 1922°F 5.73 7.81 Red 32 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 JACKSON COUNTY- continued SAMPLE 1336 A - continued Material: shale Age: Pennsylvanian - Spoon Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 3.65 5.73 7.81 Total linear shrinkage, percent 5.73 7.81 9.89 Fired colors Salmon Red Red Suggested uses: structural clay products, drain tile, and flower pots. SAMPLE 1336 B SE^ NE^ NEi sec. 18, T. 9 S. , R. 2 W. Southwest cut bank of creek just west of first bridge on north-south section line road. Bottom 8 feet of 35-foot shale section; shale, hard, medium gray, silty, very poorly bedded, semi-conchoidal fracture, lower 2 feet becomes better bedded and carbonaceous. Material: shale Age: Pennsylvanian - Abbott Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 3.65 5.73 6.77 Total linear shrinkage, percent 5.73 7.81 8.85 Fired colors Chocolate Red Red Suggested uses: structural clay products, drain tile, and flower pots. JASPER COUNTY SAMPLE 1411 SE5- SEi SE^- sec. 35, T. 7 N., R. 9 E. Northwest edge of Newton on east cut bank of tributary to Embarrass River. About 10 feet of shale exposed; shale, sandy, blue-gray, and laminated. Material: shale Age: Pennsylvanian - Mattoon Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: overfired at 2012°F Suggested uses: structural clay products, drain tile, flower pots, and sewerpipe. KANE COUNTY SAMPLE NF 150 SE5- NWi NWi sec. 24, T. 42 N. , R. 7 E. Section exposed in an abandoned clay pit. Sampled in 1933. 15 Workabil ity: good 2.08 1832°F 1922°F 3.65 5.73 5.73 7.81 Chocolate Red 22 Workabi lity: fair 2.60 1832°F 1922°F 2012°F 2.61 4.17 8.86 5.21 6.77 11.46 Salmon Salmon Red CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 33 KANE COUNTY- continued SAMPLE NF 150 - continued Pleistocene ft . in. Wisconsinan 3. Soil, black 1 2 2. Clay, upper part gray, lower part yellow, noncalcareous, grades into bed below (sample NF 150) 2 6 1. Clay, light yellow, calcareous 6 + Bed 2 is a lake clay deposited in ancient Gilberts Lake. Characteristics of Unfired Material Material: clay Reaction for carbonates: negative Color: yellow with brown cast in part of sample Hardness: medium; granular fracture Working properties: wedges easily and quickly; slightly sticky Water of plasticity, percent: 33.3 Modulus of rupture, with 50 percent standard sand: 470 lbs. per sq. in. - 13 specimens Fineness Residue, percent: 35-mesh - 2.72 Character of residue: small limonite grains Drying Air shrinkage, percent: linear 12.8 Drying conduct: satisfactory volume 43.6 Scumming: none Characteristics of Fired Material Por- Burn: Lng Total osity % Color Hard- ness shrinkage % shrin ikaqe % Cone Linear Volume Linear Volume 06 25.9 Salmon 3 0.3 0.8 13.1 44.4 03 19.1 Red 5 3.2 9.4 16.0 53.0 01 12.4 Red 5-6 5.5 15.7 18.3 59.3 3 3.7 Light maroon 6 6.6 18.6 19.4 62.2 4 1.8 Maroon 7 5.7 16.2 18.5 59.8 6 0.6 Maroon 8 5.6 15.8 18.4 59.4 8 6.3 Deep maroon 8 0.3 0.8 13.1 44.4 is reac Remarks: the sample, at cone 4, reoxidized after reduction in firing, and, at cone adily made plastic although it is slightly has better than average strength. The burn- as it has a range of probably four or five the burned ware is good, and the range of 8, was bloated and sticky. It sticky. It dries satisfactorily and ing conduct is satisfactory inasmuch cones of low porosity. The color of colors is very good. Suggested uses: common and face brick, structural tile. drain tile, quarry tile, roofing tile, and KANKAKEE COUNTY SAMPLE 1324B NWi NEi sec. 8, T. 31 N. , R. 9 E. Pit 11 of Northern Illinois Coal Corpora- tion. Lower 10 feet of shale. 22 Format ion - Francis Creek Shale 2.34 Workabil ity : good 1832°F 1922°F 2012°F 2.87 7.03 9.12 5.21 9.37 11.46 Chocolate Chocolate Chocolate 34 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 KANKAKEE COUNTY- continued SAMPLE 1324B - continued Material : shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and flower pots. SAMPLE 1324D Same location as sample 1324B. Upper 10 feet of shale. Material: shale Age: Pennsylvanian - Carbondale Forma- Water of plasticity, percent 18 tion - Francis Creek Shale Linear drying shrinkage, percent 2.08 Workability: good Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 2.09 4.69 6.77 Total linear shrinkage, percent 4.17 6.77 8.85 Fired colors Salmon Salmon Red Suggested uses: structural clay products, drain tile> and flower pots. KNOX COUNTY SAMPLES NF 363A and NF 364 Center Eg- SE^ NWi sec. 6, T. 9 N. , R. 2 E. Sampled in 1935. The following strata were exposed along a north-south road: ft. Pleistocene 6. Till and loess 11 Pennsylvanian - Carbondale Formation 5. Shale, gray to brown with ironstone concretions 5 4. Shale, black 2 3. Shale, gray to brown, thin-bedded (sample NF 364, but sampled in a small coal pit about 100 feet west of the road where the shale is 7f- feet thick) 5 2. Coal ( Colchester No. 2 Coal) 2 Pennsylvanian - Spoon Formation 1. Clay, noncalcareous, gray, much brown staining, becomes shaly in basal 6 inches (sample NF 363A) Tg- Covered SAMPLE NF 36 3A Characteristics of Unfired Material Color: yellowish gray Hardness: variable; some shattered be- Fracture: variable; part retains the tween the fingers; some too hard to fissile structure; other portions permit this weathered so that fissile structure Reaction for carbonates: cold - trace is invisible Soluble salts: no scumming Reaction for pyrite: negative Working properties: very good; a little Drying conduct: satisfactory fat CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 35 KNOX COUNTY- continued SAMPLE NF 363A - continued Drying shrinkage, percent: linear 9.3; volume 30.5 Screen test: residue on 35-mesh sieve - 33 percent; limonite exists as concre- tionary lenses, crusts, stringers, and as a bond cementing grains of silica and clay. These concretions are apparently siliceous particles, quite soft and friable, bonded with limonite. Characteristics of Fired Material Absorp- Por- Bur ning tion % osity % Color Hard- ness shrin kage % Cone Linear Volume Remarks 06 9.7 19.7 Light red 6 9.9 22.0 No scum 04 0.1 0.2 Dark red 8 14.0 36.4 Fine, glossy red color 02 0.1 0.2 Dark red 8 14.0 36.4 Fine, glossy red color 4 0.3 0.6 Dark red 8 7.2 20.0 Overburned Oxidation conduct: requires slightly prolonged oxidation treatment at temperatures lower than normal Suggested uses: the fine color, together with the low maturing temperature and the long vitrification range make this a desirable material for the manufacture of face brick. It should be noticed that this clay develops a hardness of 7 at cone 06, which is very unusual. This clay would produce either vitrified or non- vitrified ware at temperatures lower than usual. SAMPLE NF 364 Characteristics of Unfired Material Color: gray, often with yellow surface Reaction for pyrite: negative coating Soluble salts: sulfates negative Hardness: most too hard to shatter with Working properties: excellent the fingers Drying shrinkage, percent: linear 7.6 Fracture: most breaks into flakes, volume 24.5 characteristic of fissile structure Drying conduct: no difficulty noted Reaction for carbonates: cold - negative hot - negative Screen test: residue on 35-mesh sieve - 7.7 percent. Stringers, crusts, and con- cretions of siliceous material bonded with limonite. These are soft and readily disintegrated. Characteristics of Fired Material Absorp- Por- Burning tion osity Hard- shrinkage % Cone % % Color ness Linear Volume Remarks 06 14.3 27.0 Light red 5 4.4 12.6 Clear, uniform surface 1 5.6 12.4 Bright red 7 9.4 25.7 Clear, uniform surface 5 0.15 0.3 Brownish red 8-9 10.3 27.8 Clear, uniform surface Oxidation conduct: not difficult to oxidize, but should be oxidized at a lower temperature than usual 36 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 KNOX COUNTY- continued SAMPLE NF 364 - continued Warpage: none noted Remarks: matures at a low temperature, has a long firing range, and can be vitri- fied Suggested uses: face brick, sewer pipe, paving brick, building tile, conduits, roofing tile, drain tile, common brick, and art pottery. SAMPLES NF 365, NF 366, and NF 367 SEi NWi NEi sec. 6, T. 9 N. , R. 2 E. Sampled in 1935. Composite section of strata exposed on the west side of Brush Creek south of the road. ft. in. Covered, probably about 30 feet of bedrock, including Col- chester No. 2 Coal, and 10 to 20 feet of loess and till 40-50 Pennsylvanian - Spoon Formation 9. Sandstone, fine-grained 8± 8. Shale, gray and brown 2 6 7. Coal (Wiley Coal?) 8-12 6. Fireclay, gray and brown (sample NF 367) 4 5. Coal 2-4 4. Fireclay, gray to dark gray (sample NF 366) 5 6 3. Sandstone, quartzitic, fine-grained l"2a 2. Clay, sandy white and yellow with a 4-inch bed of soft sandstone near base; grades into bed below (sample NF 365) 4 1. Sandstone 2 6 Covered SAMPLE NF 365 Characteristics of Unfired Material Color: gray Working properties: very good - some- Hardness: crushable between the fingers what short Reaction for carbonates: cold - negative Drying shrinkage, percent: linear 5.2 hot - trace volume 16.5 Reaction for pyrite: trace Drying conduct: excellent Soluble salts: soluble iron compound Screen test: residue on 35-mesh sieve - 0.1 percent. Silica sand; clay contains considerable gritty material which passes this screen Characteristics of Fired Material Absorp- tion % Por- osity % Color Hard- ness Burning shrinkage % Cone Linear Volume Remarks 06 1 6 15.5 15.0 10.6 28.4 28.1 21.4 Pinkish yellow Yellow Buff 4 3 7 0.3 1.3 3.6 0.9 3.8 10.5 Red surface scum Traces of pink Oxidation conduct: no oxidation problem Warpage: none Suggested uses: drain tile, common brick, or buff face brick. May have some pos- sible uses as a low-grade refractory. Could be colored readily by mixing a little red-burning clay, as it forms good red colors readily in the presence of iron compounds. CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 37 Color: 1 gray Hardness : Fracture: Reaction Screen te nite; Cone KNOX COUNTY- continued SAMPLE NF 366 Characteristics of Unfired Material ight gray mixed with some dark Reaction for pyrite: present Working properties: excellent readily friable Drying shrinkage, percent: linear 7.6 granular volume 24.5 for carbonates: cold - negative Drying conduct: excellent hot - negative st : residue on 35-mesh sieve - 0.5 percent. Sandstone, coal, and limo- small amount of pyrite Characteristics of Fired Material Absorp- tion Por- osity % Color Hardness 29.0 Light pink 3 13.4 Pinkish buff 7 8.6 Buff 8 8.4 Buff 9 0.8 Buff 9 06 16.1 1 6.2 2 4.0 3 3.7 6 0.4 Oxidation conduct: requires reasonable oxidation period Suggested uses: typical terra cotta clay; would make good buff face brick; could be used for conduits and stoneware. Burning shrir ikage % Linear Volume 1.0 3.2 7.1 19.7 7.2 20.1 9.0 24.6 9.1 25.0 SAMPLE NF 367 Characteristics of Unfired Material Color: greenish gray Soluble salts: sulfates present Hardness: 3 Working properties: fair, a fat clay; Fracture: poor, fissile tends to laminate Reaction for carbonates: cold - present Drying shrinkage, percent: linear 12.5 hot - negative volume 42.2 Reaction for pyrite: abundant Drying conduct: likely to crack unless carefully dried Screen test: residue on 35-mesh screen - 0.65 percent; probably 85 percent pyrite; remainder is coal, calcite, and gypsum Characteristics of Fired Material Absorp- Por- Burning tion % osity % Color Hard- ness shrir ikage % Cone Linear Volume Remarks 06 8.9 18.1 Salmon pink 7 4.7 13.5 No scum 04 0.5 1.0 Dark buff 9 8.0 22.2 Some scum 6 25.0 32.8 Light buff 7 12.9 34.4 Overf ired; bloated uni- formly and swelled 34.4 percent of dry volume; maintained square edges 38 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 KNOX COUNTY- continued SAMPLE NF 367 - continued Oxidation conduct: very difficult to oxidize; oxidation must be carried out around 900°F or bloating occurs Soluble salts: sulfates present Suggested uses: the uniform swelling of this clay when overfired suggests useful- ness as an ingredient in ladle brick. However, this action may occur at too low a temperature, and this would have to be checked. The ease, the complete- ness, and the low temperature of bloating of this clay when not properly oxidized would make it a useful material for the production of "Haydite". The high degree of hardness achieved at the extraordinarily low maturing temperature would make it useful for face brick, hollow tile, and perhaps roofing tile. SAMPLE NF 368 Sg- Nj- SWi sec. 25, T. 11 N. , R. 1 E. Sampled in 1935. Exposure in small gully west of barn: ft. in. Pennsylvanian - Carbondale Formation 6. Shale, slaty 3 5. Coal (Springfield No. 5 Coal) 2 4. Shale, gray and yellow-brown 10 3. Shale, yellow-brown 10 2. Shale, dark gray with thin, cream-colored partings 2 1. Limestone, fine-grained 8 Covered Sample NF 368 is from the shale comprising beds 2, 3, and 4. Characteristics of Unfired Material Color: gray; portions darker gray; Working properties: fair - somewhat fat some yellow surface coating Soluble salts: present Hardness: 1; some fissile, some granular Drying shrinkage, percent: linear 12.5 Reaction for carbonates: cold - positive volume 42.5 hot - negative Drying conduct: must be dried slowly Reaction for pyrite: trace to prevent cracking Screen test: residue on 35-mesh screen - 3.5 percent. Limestone, gypsum, coal, and root casts Characteristics of Fired Material Absorp- tion % Por- osity % Color Hard- ness Burning shrinkage % Cone Linear Volume Remarks 06 04 6 8.5 6.2 9.6 17.8 13.1 14.0 Light red Dark red Chocolate 6 7 8 4.2 6.6 7.8 12.1 18.5 21.8 Heavy scum Heavy scum Bloated Oxidation conduct: requires somewhat prolonged oxidation period at lower temperatures Suggested uses: common brick, face brick, hollow tile, and drain tile. SAMPLE 1347 A SEy sec. 17, T. 11 N. , R. 2 E. Purington Brick Company pit southeast of East Galesburg. Approximately 20 feet of gray shale exposed. CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 39 KNOX COUNTY- continued SAMPLE 1347 A - continued Material: shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors 22 2.60 Age: Pennsylvanian - Carbondale Forma- tion - Purington Shale Workability: good 1832°F 1.57 4.17 Salmon 1922°F 3.65 6.25 Salmon Suggested uses: structural clay products, drain tile, and flower pots. LA SALLE COUNTY SAMPLES W 7 and W 8 33 N., R. 1 E. In pit of Alpha Portland Cement SEi SEi NWi sec. 14, T. Company. Sampled in 1931. Pennsylvanian - Mattoon Formation ft. in. 7. Clay, red (sample W 8) 5 6. Shale, red, with 1-to 2-inch layers of green shale 2g— 3 5. Shale, red, gray splotches, locally contains limestone concretions and fossils (sample W 7) 8 4. Clay, gray 1 3. Limestone, lenticular 8 2. Covered 5 Pennsylvanian - Bond Formation 1. Limestone (LaSalle Limestone) SAMPLE W 7 Characteristics of Unfired Material The material is a hard, sandy shale, purplish red in color, has a stony fracture, medium plasticity over a fair range, and requires 28.4 percent water to develop its normal medium-soft, oily working consistency. A low-medium bonding strength is indicated by 190 pounds per square inch for the modulus of rupture. It dries slowly under ordinary atmospheric conditions, scums slightly, and has a shrinkage of 7.2 percent. When slaked and washed on a 40-mesh sieve, 38.6 percent residue remains which consists of unslaked original material and small mica flakes and quartz grains which are probably bonded together with lime. Treatment with cold hydrochloric acid causes generous evolution of gas, indi- cating the presence of carbonates. When burned, the clay oxidizes readily. Characteristics of Fired Material Linear shrinkage Cone Porosity % Color Hardness Burning Total 04 1.0 Medium dark red Steel hard 10.5 17.7 02 0.4 Medium dark red 10.6 17.8 01 0.3 Medium dark red 10.5 17.7 3 0.2 Darker red 8.6 15.8 4 0.7 5.2 12.4 6 8.1 Metallic, swelled 3.4 10.6 40 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 LA SALLE COUNTY- continued SAMPLE W 7 - continued Remarks: this material is vitrified at cone 04 and practically nonabsorbent. It begins to overburn above cone 01 and is badly overburned at cone 6. The shrink- age is medium. The medium dark red color is reasonably uniform from cone 04 to cone 3. Suggested uses: sewer brick, quarry tile, roof and floor tile, hollow ware - unless the soluble salts are too troublesome. SAMPLE W 8 Characteristics of Unfired Material The material is a clay of purplish red color with gray mottling, has an ir- regular hackly fracture, and requires 33.3 percent water to develop its normal good working consistency. A low-medium bonding strength is indicated by the value of 182 pounds per square inch for the modulus of rupture. It dries slowly under ordinary atmospheric conditions, scums somewhat, and has a shrinkaqe of 11.6 percent. When slaked and washed on a 40-mesh sieve, 3.4 percent residue remains, con- sisting of red lumps with varying concentration of mica and a few lumps of quartz grains bonded with calcium carbonate. Treatment with cold hydrochloric acid causes violent evolution of gas, indi- cating the presence of carbonates. When burned, the clay oxidizes readily. Characteristics of Fired Material Linear shrinkage Cone Porosity % Color Hardness Burning Total 04 18.2 Red Steel hard 5.4 17.1 02 13.8 (?) Red Steel hard 6.0 17.7 01 18.7 Red Steel hard 3.3 15.0 1 0.9 Darker red Steel hard 7.0 18.7 3 0.5 Overburned 4.9 16.6 6 Slagged Remarks: the clay has a good red color and considerable porosity up to and includ- ing cone 01. Its total shrinkage is high. Above the temperature mentioned, it vitrifies rapidly, overburns at cone 3, and is completely fused at cone 6. Suggested use: common brick. SAMPLE 1324 A SWi SWi sec. 5, T. 33 N., R. 4 E. Laclede Christy Division, H. K. Porter Company pit, T§- miles east of Ottawa, north of U. S. Highway 6, east of Illinois Highway 71. Lower 10 feet of blue-gray, clayey shale. Material: shale Age: Pennsylvanian - Carbondale Forma- Water of plasticity, percent 27 tion - Francis Creek Shale Linear drying shrinkage, percent 3.90 Workability: good Fired temperatures 1832°F 1922°F 2012°F Linear firing shrinkage, percent 4.75 8.60 9.12 Total linear shrinkage, percent 8.85 12.50 13.02 Fired colors Chocolate Chocolate Chocolate Suggested uses: drain tile, sewerpipe, and building tile and block. 20 tion - Fr, ancis Creek Shale 2.60 Workabil ity : good 1832°F 1922°F 2012°F 2.08 4.69 7.29 4.68 7.29 9.89 Chocolate Chocolate Chocolate CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 41 LA SALLE COUNTY- continued SAMPLE 1324 C Same location as sample 1324 A. Upper 10 feet of shale,which contains more sand and silt. Material: shale Age: Pennsylvanian - Carbondale Forma- Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: drain tile, sewerpipe, and building block and tile. SAMPLE 1403 SWi SWy SWi sec. 9, T. 33 N., R. 3 E. Pit of Illinois Valley Mineral Company, Lg- miles west of Ottawa along north bluff of Illinois River. Approximately 8 feet of blue-gray shale above Colchester (No. 2) Coal. Material: shale Age: Pennsylvanian - Carbondale Forma- Water of plasticity, percent 25 tion - Francis Creek Shale Linear drying shrinkage, percent 3.12 Workability: good Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 4.17 4.73 2.08 Total linear shrinkage, percent 7.29 8.85 1.04 Fired colors Light salmon Light salmon Remarks: considerably overfired at 2012°F} pyrite Suggested use: drain tile. LAWRENCE COUNTY SAMPLE 1426 SE5- SWi NWi sec. 5, T. 3 N., R. 11 W. East cut bank of Embarrass River, north of U. S. Highway 50. Upper 10 feet of shale bank 30 to 40 feet in height, overburden 10 to 15 feet; shale, brownish gray, weathered. Material: shale Age: Pennsylvanian - Bond Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and flower pots. LIVINGSTON COUNTY SAMPLE 1321 A Sw£ SWi sec. 34, T. 27 N., R. 8 E. Diller Brick and Tile Company pit north of Chatsworth. Approximately 15 feet of blue-gray till. 20 Workabil ity: good 2.08 1832°F 1922°F 2012°F 2.60 3.13 8.34 4.68 5.21 10.42 Salmon Salmon Red Age: PI worth Workabil eist ity: .ocene - Wisconsinan - Chat good 1832°F 0.79 4.17 Chocolate 1922°F 0.79 4.17 Chocolate 2012°F 4.95 8.33 Chocolate 42 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 LIVINGSTON COUNTY- continued SAMPLE 1321 A - continued Material : till Water of plasticity, percent 21 Linear drying shrinkage, percent 3.38 Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: common brick, drain tile, and building tile and block. MACOUPIN COUNTY SAMPLE 1407 NEi NWi NEi sec. 9, T. 9 N. , R. 7 W. South cut bank of Honey Creek south of road. Approximately 15 feet of sandy shale exposed, overburden thick. Material: shale Age: Pennsylvanian - Modesto Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and flower pots. MADISON COUNTY SAMPLE 1344 A SE-i SEy NE£ sec. 35, T. 6 N. , R. 10 W. Alton Brick Company pit east of road south of Coal Creek, north of Alton. Lower 10 feet of dark gray shale. Material : shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and flower pots. MARSHALL COUNTY SAMPLE W 141 SWi NEi SEi sec. 16, T. 12 N., R. 9 E. The following bedrock strata were exposed along Gimlet Creek above and below the road : 20 Workabil ity: good 2.08 1832°F 1922°F 2012°F 3.13 3.13 8.91 5.21 5.21 10.99 Salmon Salmon Red 18 tion - Francis Creek Sha Te 1.04 Workabil 1832°F 1.56 2.60 Salmon ity: good 1922°F 3.65 4.69 Salmon 2012°F 7.29 8.33 Red CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 43 MARSHALL COUNTY- continued SAMPLE W 141 - continued Pennsylvanian - Modesto Formation 7. Limestone, nodular, gray, dense, weathered light gray to white 6. Shale, dark gray and dark red 5. Limestone, dense, gray 4. Shale, gray with red streaks 3. Limestone, reddish brown, dense 2. Shale, greenish gray, sandy, micaceous (sample W 141) 1. Sandstone, greenish gray, generally thin-bedded Characteristics of Unfired Material ft. 5 5 4 20-30 The material is a moderately hard, sandy shale, light gray in color, has a stony and conchoidal fracture, low (mealy) plasticity over a short range, and re- quires 23.9 percent water to develop its normal medium-soft working consistency. A medium-low bonding strength is indicated by a value of 133 pounds per square inch for the modulus of rupture. It dries rather rapidly and without difficulty under ordinary atmospheric conditions, and has a shrinkage of 4.9 percent. When slaked and washed on a 40-mesh sieve, 28.9 percent residue remains which consists of unslaked original material with a few small pyrite grains. Treatment with hot and cold hydrochloric acid causes mild evolution of gas, indicating the presence of carbonates. When burned, the clay oxidizes readily. Characteristics of Fired Material Linear shrinkage % Cone Porosity % Color Hardness Burning Total 05 26. 4 Salmon 2.8 7.7 01 15.4 Red Steel hard 6.6 11.5 2 10.8 Red Steel hard 8.0 12.9 3 9.6 Darker i ed Steel hard 8.1 13.0 6 27.1 Overburr black led Steel hard 0.3 5.2 Remarks: this material vitrifies rapidly, reaching a minimum porosity above cone 3 and overburning seriously at cone 6. The total shrinkages are medium and high medium. The color is a good red which darkens rapidly. Suggested uses: common brick. SAMPLE NF 215 SWi NEi SEi sec. 16, T. 12 N., R. 9 E. Sampled in 1934. Beds exposed are as follows: Pennsylvanian - Modesto Formation 5. Limestone, nodular, gray (Lonsdale Limestone) 4. Shale, thin-bedded, dark gray 3. Shale, maroon or dark red, calcareous 2. Shale, gray, calcareous 1. Limestone, shale, and sandstone Covered ft. 5 3 1 6 2 1 10 26 2 Sample NF 215 is taken from beds 2, 3, and 4. 44 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 MARSHALL COUNTY- continued SAMPLE NF 215 - continued Characteristics of Unfired Material Material: clay Reaction for carbonates: positive Color: dark mustard; small reddish particles with a yellow-gray back- ground visible Hardness: medium; laminated fracture Working properties: wedges easily and quickly; slightly sticky Residue, percent: 35-mesh - 0.37 Air shrinkage, percent: linear 13.0 volume 44.3 Fineness Character of residue: Drying calcite Drying conduct: satisfactory Scumming: trace Cone Absorption % Characteristics of Fired Material Color Hardness Remarks 06 6.9 Salmon 6 02 5.3 Red 7 4 1.6 Maroon 8 Black cored from reduction after previous oxidation; not overfired Remarks: has fine color and range of color Suggested uses: common brick, face brick, roofing tile, quarry tile, structural tile, and drain tile. SAMPLE 1400 SEi NWi sec. 23, T. 12 N. , R. 9 E. Roadcut west of Illinois Highway 29 be- tween Hydraulic Press Brick plant and Sparland. Lower 15 feet of weathered gray shale, overburden thick. Material: shale Age: Pennsylvanian - Modesto Formation ■ Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and flower pots. 22 Farmington Shale 1.04 WorkabL Lity: fair 1832°F 1922°F 2012°F 5.21 5.21 9.90 6.25 6.25 10.94 Salmon Salmon Red SAMPLE W 43 SEi NWi NEi sec. 27, T. 12 N. , R. 9 E. Sampled in 1930. Bedrock exposed in cut bank of stream consists of: ft. Pennsylvanian - Modesto Formation 6. Shale, gray, thick bedded; contains small limestone concretions (Farmington Shale) (sample W 43) 15 5. Shale, soft, black, in distinct bedding 4. Shale, gray, slaty, thin-bedded 1 3. Coal, with 2"-inch clay seam 8 inches above base (Danville No. 7 Coal) 3 2. Fireclay 9 1. Sandstone, massive, gray, calcareous, micaceous 6 Covered CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 45 MARSHALL COUNTY- continued SAMPLE W 43 - continued Characteristics of Unfired Material The material is a hard, dark bluish gray shale, has a slate-like fracture, has good plasticity over a moderate range, and requires 33.9 percent water to de- velop its normal medium-stiff working consistency. It dries without difficulty but somewhat slowly under ordinary atmospheric conditions and has a shrinkage of 9.2 percent. When slaked and washed on a 40-mesh sieve, 3.6 percent residue remains, con- sisting of unslaked original material and small agglomerations of pyrite crystals. Treatment with cold and hot hydrochloric acid causes mild evolution of gas indicating the presence of carbonates. When burned, the clay oxidizes with great difficulty. Characteristics of Fired Material Linear shrinkage % Cone Porosity % Color Hardness Burning Total 06 5.0 Red 11.7 20.9 01 19.3 Red 8.0 1.2 1 10.0 Red 9.5 0.3 2 23.6 Red 15.8 6.6 Remarks: all test pieces cracked or swelled; this material overburned and bloated within the low temperature range studied Suggested uses: common brick burned at lower temperatures or as a bloated aggregate at higher temperatures than cone 05. MC D0N0UGH COUNTY SAMPLE 1325A SE-5- NE^- sec. 12, T. 5 N., R. 4 W. Colchester Brick and Tile Company pit, north edge of Colchester. Lower 20 feet of shale above Colchester (No. 2) Coal. Material : shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and sewerpipe. 20 tion - Francis Creek Shale 3.12 Workabil ity: good 1832°F 1922°F 2012°F 2.61 5.73 7.30 5.73 8.85 10.42 Salmon Salmon Red MENARD COUNTY SAMPLE 1330 A SWi SEi sec. 11, T. 18 N. , R. 7 W. Springfield Clay Products Company pit north of Petersburg. Approximately 35 feet of shale with 20 feet of overburden. Material : shale Water of plasticity, percent 23 Linear drying shrinkage, percent 3.38 Age: Pennsylvanian - Modesto Formation Workability: good 46 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 1832°F 1922°F 2012°F 3.91 8.60 9.12 7.29 11.98 12.50 Salmon Red Red MENARD COUNTY- continued SAMPLE 1330 A - continued Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and sewerpipe. MERCER COUNTY SAMPLE 1348A SWi NW5- sec. 8, T. 14 N., R. 2 W. Shale pit of Hydraulic Press Brick Company at Shale City. Approximately 30 feet of blue-gray shale. Material: shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: overfired at 2012°F Suggested uses: structural clay products, drain tile, and sewerpipe. 24 tion - ■ Fr ancis Creek Sha ile 1.56 1832°F 2.09 3.65 Salmon 1922°F 5.73 7.29 Salmon 2012°F 7.82 9.38 Red MONROE COUNTY SAMPLE Z Ng- NW?- NEi sec. 3, T. 2 S. , R. 10 W. Sampled in 1932. Exposure in drift of coal mine: Pennsylvanian - Carbondale Formation 5. Limestone, dark gray, dense 4. Coaly clay or impure coal 3. Coal 2. Underclay, dark gray (sample Z) 1. Underclay, with limestone nodules Covered ft. l£-3 3± 8-12 3-5 6± Characteristics of Unfired Material Material: underclay Reaction for carbonates: yes Color: gray Reaction for pyrites: yes Hardness: 1 on Moh's scale Gypsum: present as fine particles Working properties: packs badly when ground; works well in mold; has medium plasticity Drying: air shrinkage, dry basis - linear 9.3 percent Characteristics of Fired Material Linear shrinkage % Cone Color Hardness Burning Total Remarks 010 Buff 2.3 11.6 Bars have rough 07 Light brown Steel hard 2.3 11.6 surface and are 01 Olive-drab 3.3 12.6 badly checked 3 Overburned CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 47 MONROE COUNTY- continued SAMPLE Z - continued Remarks Drying shrinkage: high-medium Burning shrinkage: low-medium (cone 01 ) Color range: variable Plasticity: medium Vitrification: overburned at cone 3 Suggested uses: common brick, hollow brick, face brick, glazed brick, enameled brick, and fireproof ing. MONTGOMERY COUNTY SAMPLE 1412 NWi SW* sec. 30, T. 8 N. , R. 2 W. One and one-half miles northeast of Coffeen on west bank of East Fork Creek. Five to six feet of iron stained, gray shale, with plant fossils and coal band in middle of exposure. Material: shale Age: Pennsylvanian - Bond Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: overfired at 2012°F Suggested uses: structural clay products, drain tile, and flower pots. PEORIA COUNTY SAMPLE R 216 Ng- SEt NE-5- sec. 26, T. 8 N. , R. 7 E. Sample was taken from 9 feet of loess which is mostly brown and noncalcareous; lower 1 to 2 feet is gray and calcar- eous. Sampled in 1931. Age: Pleistocene - Wisconsinan - Peoria loess. Characteristics of Unfired Material The material is a yellow, surface clay, is a friable mixture of clayey loam and fine sand, has medium plasticity over a moderate range, and requires 25.6 per- cent water to develop its normal medium working consistency. Its bonding strength is high-medium with a value of 507 pounds per square inch. It dries fairly rapidly and without difficulty under ordinary atmospheric conditions, scums slightly, and has a shrinkage of 5.5 percent. When slaked and washed on a 40-mesh sieve, 0.6 percent residue remains that contains a few pyrite and silica grains but consists largely of brown and black slag-like particles that, because they are attacked by hydrochloric acid, are thought to be quartz bonded with hydrous iron oxide and/or carbonates of lime and iron. Treatment with hot hydrochloric acid causes generous evolution of gas, in- dicating the presence of carbonates. When burned, the clay oxidizes readily. Characteristics of Fired Material Linear shrinkage % 21 Workabi] .ity: good 2.60 1832°F 1922°F 201 2° F 3.65 5.21 2.61 6.25 7.81 5.21 Salmon Salmon Red Cone Porosity % Hardness Burning Total 04 33.1 Salmon 0.4 5.9 02 23.3 Red 4.2 9.7 1 15.8 Deep red Steel hard 6.5 12.0 3 4.2 Deep red Steel hard 8.5 14.0 6 Practical^ r fused 25 Workabil ity: good 5.21 1832°F 1922°F 2012° 5.21 6.25 -- 10.42 11.46 5.21 Salmon Red Brown 48 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 PEORIA COUNTY- continued SAMPLE R 216 - continued Remarks: this clay vitrifies to a low porosity at cone 3, and is overburned be- tween that point and cone 6. It has a good red color between cones 02 and 3, and possibly somewhat higher. The total shrinkages are medium, except at cone 3, which is high-medium. The oxidation conduct is good. Suggested uses: face and common brick, sewer brick, hollow ware, tile, and fire- proofing. SAMPLE 1402 SE-f NW4 sec. 13, T. 11 N. , R. 6 E. Northwest corner of Princeville on east bank of Prince Run Creek. About 8 feet of gray shale exposed with thin overburden. Material: shale Age: Pennsylvanian - Modesto Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: overfired at 2012°F Suggested uses: structural clay products, drain tile, flower pots, and sewerpipe. SAMPLES W 14X and W 143D NEi SEi NEi sec. 8, T. 11 N. , R. 9 E. Sampled in 1930. Age: Pennsylvanian - Modesto Formation. Five and a half feet of Lonsdale Limestone is exposed in a gully and contains a lens of light gray and light tan material (resembling flint clay) up to 1 foot thick; the extent of the lens is unknown. The deposit was sampled because it is unusual in character and occurrence. Sample W 143C was taken from the tan clay and sample W 143D from the light gray clay. SAMPLE W 143C Characteristics of Unfired Material The material is a fairly hard, sandy clay, very light tan in color, has a stony fracture and fair plasticity over a moderate range, and requires 24.2 per- cent water to develop its normal good working consistency. A modulus of 165 pounds per square inch indicates that the material has a low-medium bonding strength. It dries fairly rapidly under ordinary atmospheric conditions without dif- ficulty, and has a shrinkage of 5.3 percent. When slaked and washed on a 40-mesh sieve, 69.9 percent residue remains, con- sisting partly of unslaked original material resembling flint clay that microscopic examination shows to be quartz grains bonded with a white substance, and partly of brown grains and probable limestone. Treatment with cold hydrochloric acid causes violent evolution of gas, indicat- ing the presence of carbonates. Characteristics of Fired Material Cone Porosity % Color Hardness Linear < Burning ;h rin kage % Total 05 02 01 33.8 29.9 29.5 Gray-white Gray-white Gray-white 1.1 2.9 3.2 6.4 8.2 8.5 CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 49 PEORIA COUNTY- continued SAMPLE W 143C - continued Characteristics of Fired Material - continued Linear shrinkage % Cone Porosity % Color Hardness Burning Total 2 27.1 Gray-white 3.7 9.0 3 27.1 Light gray 4.0 9.3 6 18.5 Oatmeal Steel hard 6.8 12.2 8 16.6 Oatmeal Steel hard 7.5 12.8 9 12.2 Oatmeal Steel hard 7.7 13.0 11 9.1 Oatmeal Steel hard 7.7 13.0 14 12.2 Overburned 4.3 9.6 Remarks: this is an open burning material which is overburned at cone 14. The total shrinkage is medium to high-medium. Carbonates are present. Suggested uses: face or common brick, faience tile, hollow ware, pottery, and architectural terra cotta. SAMPLE W 143D Characteristics of Unfired Material The material is a fairly hard, sandy clay, grayish white and also stained; it has a conchoidal fracture and fair plasticity over a moderate range; it requires 25.5 percent water to develop its normal good working consistency. It dries fairly rapidly and without difficulty under ordinary atmospheric con- ditions, and has a shrinkage of 6.8 percent. When slaked and washed on a 40-mesh sieve, 77.2 percent residue remains, con- sisting of unslaked original material. Treatment with hot hydrochloric acid causes moderate evolution of gas, indi- cating the presence of carbonates. Characteristics of Fired Material Linear shrinkage % Cone Porosity % Color Hardness Burning Total 05 28.8 Gray-white 3.4 10.2 02 25.5 Gray-white 4.8 11.6 01 24.4 Gray-white 5.1 11.9 2 23.5 Light gray 5.4 12.2 4 21.3 Light gray Steel hard 6.3 13.1 6 13.1 Dark oatmeal Steel hard 7.9 14.7 8 11.0 Dark oatmeal Steel hard 8.7 15.5 9 3.7 Stoneware gray Steel hard 9.1 15.9 11 0.3 Stoneware gray Steel hard 8.9 17.7 14 18.0 Stoneware gray Steel hard 4.3 11.1 Remarks: this material vitrifies slowly, becoming quite dense at cone 9, practically nonabsorbent at cone 11, and overburns decidedly at cone 14. The color changes steadily with comparatively short heat ranges (for brick). The total shrinkages range from medium to high-medium. Suggested uses: face brick, tile, architectural terra cotta, hollow ware, and stoneware. 23 Workabi] .ity : fair 4.42 1832°F 1922°F 2012°F 4.43 7.56 7.04 8.85 11.98 11.46 Salmon Red Brown 50 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 PERRY COUNTY SAMPLE 1323B NWi SEi NWj sec. 25, T. 4 S. , R. 3 W. South cut bank of Swanwick Creek 125 yards west of Pinkneyville-Nashville road crossing. Approximately 15 feet of medium gray to olive-gray, well laminated shale, lower part darker than upper, more silty near top. Material: shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear firing shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: overfired at 2012°F Suggested uses: structural clay products, drain tile, flower pots, and sewerpipe. SAMPLE 1323A NEi SWi NEi sec. 5, T. 4 S. , R. 4 W. About 2 miles northeast of Coulterville, along east bank of north-flowing tributary to Mud Creek, about one-eighth mile east of road. Twelve feet of gray-brown grading down into blue-gray, hard, well laminated shale. Material: shale Age: Pennsylvanian - Modesto Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, flower pots, and sewerpipe. SAMPLE X SWi NEi Sw£ sec. 20, T. 5 S. , R. 4 W. Along branch of Rock Fork Creek. Sam- pled in 1931. Age: Pennsylvanian - Modesto Formation. The sample was taken from a small outcrop of 2 feet of red, brown, and yellow clay resembling flint clay. The base of the clay is covered; it is overlain by 10 feet of clay and silt except in the stream bed. The clay is sandy, nonbedded, and breaks into irregular fragments with a conchoidal fracture. The clay may be associ- ated with sandstone. Characteristics of Unfired Material Material: clay Reaction for carbonates: none Color: pink, light buff, pinkish buff, Reaction for pyrites: none yellowish brown, or black Hardness: 1 on Moh's scale Working properties: lean Drying: air shrinkage, dry basis - linear 6.5 percent 21 Workabil ity: fair 3.12 1832°F 1922°F 2012°F 3.13 7.81 8.34 6.25 10.93 11.46 Salmon Red Red CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 51 PERRY COUNTY- continued SAMPLE X - continued Characteristics of Fired Material Linear shrinkage % Cone Porosity % Color Hardness Burning Total 010 Pink Does not attain 0.9 7.4 07 Orchid steel hardness 2.2 8.7 01 Light brown in this range 3.6 10.1 3 Absorbent Light tan 4.1 10.6 PCE value (fusion test): cone 18 - brownish black Remarks Drying shrinkage: low-medium (plastic basis) Color range: 0. K. Burning shrinkage: low-medium at cone 4 Plasticity: lean Vitrification: still absorbent at cone 3; not steel hard Suggested uses: common, hollow, face, glazed, or enameled brick; fireproof ing; quarry, roofing, faience, and tesseral and encaustic tile. PIKE COUNTY SAMPLES R 119 and R 120 SE^ SW? sec. 13, T. 7 S. , R. 3 W. Cut along Gulf, Mobile, and Ohio Railroad three-fourths mile east of Straut. Sampled in 1930. Age: Pennsylvanian - Spoon Formation. Sample R 119 was taken from brown clay exposed in ditch along the railroad right-of-way at the west end of the cut; sample R 120 was taken from a red clay exposed in a ditch along the right-of-way at the west end of the cut. SAMPLE R 119 Characteristics of Unfired Material This is a medium-hard, dense clay, lemon-tan with occasional deep red mot- tling. It has a stony fracture. When 28 percent water is added to the material, the mass becomes moderately plastic throughout a medium range. Under ordinary room conditions of temperature and humidity, it dries safely but slowly with a linear shrinkage of 7.6 percent. It has a medium bonding strength with a value of 229 pounds per square inch for the modulus of rupture. A residue consisting of 82 percent of unslaked material is retained on a 40- mesh sieve. This has the appearance of aggregates of fine quartz particles. When the clay is tested with dilute hydrochloric acid, there is no reaction. When burned, the clay oxidizes readily. Characteristics of Fired Material Linear shrinkage % Cone Porosity % Color Hardness Burning Total 04 23.5 Salmon 5.8 13.4 01 17.6 Red Steel hard 7.7 15.3 1 17.3 Red Steel hard 7.7 15.3 2 17.2 Red Steel hard 7.9 15.5 3 15.0 Red Steel hard 8.4 16.0 6 12.8 Red Steel hard 8.6 16.2 8 11.2 Red Steel hard 8.8 16.4 9 8.0 Deep wine- ■red Steel hard 6.1 13.7 12 0.7 Deep wine- ■red Steel hard 7.5 15.1 52 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 PIKE COUNTY- continued SAMPLE R 119 - continued Remarks: the porosity changes are uniformly progressive up to cone 8; beyond that point the clay becomes nonporous and apparently is very slightly overburned at cone 12. The colors developed are attractive and sufficiently uniform over a wide range of temperature (cone 01 to cone 9). The total linear shrinkages are high-medium and very uniform throughout the whole range of temperature. Suggested uses: face brick, common brick, faience tile, hollow ware, and roofing tile. SAMPLE R 120 Characteristics of Unfired Material The material is a red clay, consisting of a mixture of hard and soft lumps. When 38.9 percent water is used, a good working consistency is developed. A medium bonding strength is indicated by the modulus of rupture of 229 pounds per square inch. The moist clay dries slowly under ordinary room conditions without defect, and has a shrinkage of 11.2 percent. When slaked and washed through a 40-mesh sieve, 7.7 percent residue is re- tained, which is a hard, white fragment of sandy material and some lignite. Treatment with dilute hydrochloric acid gave a negative result for carbonates. When burned, the clay oxidizes readily. Characteristics of Fired Material Linear shrinkage % Cone Porosity % Color Hardness Burning Total 04 13.6 Red 10.4 21.6 01 12.0 Red Steel hard 12.1 23.3 1 0.4 Red Steel hard 12.3 23.5 2 0.1 Red Steel hard 12.3 23.5 3 0.1 Red Steel hard 12.5 23.7 6 0.8 Red Steel hard 12.2 23.4 8 0.3 Red Steel hard 11.9 23.1 9 3.9 Red Steel hard 6.3 17.5 12 1.3 Red Steel hard 6.1 17.3 Remarks: this material vitrifies slowly, becoming nonporous at cone 1 and over- burning, but not seriously, at cone 9. It possibly may be safely used up to and including cone 12. The total shrinkage is high at all temperatures. The color is very attractive and the commercial burning range is unusually long (cone 04 to cone 9). Suggested uses: face brick, tile, hollow ware, pottery, sewer brick, and fire- proofing. RANDOLPH COUNTY SAMPLE NF 208 NEi SWi SEj- sec. 24, T. 5 S. , R. 5 W. Sampled in 1934. Age: Pennsylvanian - Carbondale Formation. The sample was taken from a 2-foot exposure of gray and cream clay in a trench in the wall of a creek. The clay is probably overlain by sandstone and may be as much as 4 feet thick. CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 53 RANDOLPH COUNTY- continued SAMPLE NF 208 - continued Characteristics of Unfired Material Material: clay Working properties: easily worked; firm Color: dark gray through silver-gray; but not sticky some yellow particles Water of plasticity, percent: 33.6 Hardness: medium; fracture coarsely Drying conduct: successfully withstood granular very severe drying conditions Scumming: none Characteristics of Fired Material Cone Absorption % Color Hardness 6 1.1 Bright salmon 8 Suggested uses: common and face brick, possibly structural tile. SAMPLE NF 123 NWi NEi sec. 34, T. 5 S. , R. 6 W. Sampled in 1933. Age: Pennsylvanian - Carbondale Formation. The sample was taken from the underclay of the Harrisburg (No. 5) Coal at two places 500 feet apart in a mine. Characteristics of Unfired Material Material: clay Color: dark gray; good uniformity, al- Reaction for carbonates: negative though some slight brown staining Hardness: typical; laminated fracture Working property: works very well Fineness Residue, percent: 35-mesh - 1.29 Character of residue: pyrite and bitu- minous material Drying Air shrinkage, percent: linear 11.4 Drying conduct: satisfactory volume 38.3 Scumming: trace Characteristics of Fired Material Cone Absorption % Color Hardness Remarks 06 4.6 Salmon 4 02 0.5 Light brown 7 Vitreous fracture 4 24.5 Tan 5 A small black ring near outside sur- face owing to re- duction after pre- vious oxidation; badly bloated Suggested uses: common and face brick, roofing tile, quarry tile, drain tile, and structural tile unless lamination is serious. SAMPLE 1338A NWi SWi SEi sec. 5, T. 7 S. , R. 5 W. Near Wine Hill along gully flowing south, due south of church in Wine Hill. Approximately 10 feet of shale, greenish gray and silty in bottom 2 feet, grades upward to green and purple; less silty and more weathered in upper 8 feet. 9 Workabil ity : good 3.12 1832°F 1922°F 2.09 4.17 5.21 7.29 Buff Buff 54 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 RANDOLPH COUNTY- continued SAMPLE 1338A - continued Material: shale Age: Pennsylvanian - Caseyville Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 2.09 4.17 5.21 Total linear shrinkage, percent 5.21 7.29 8.33 Fired colors Buff Buff Buff Suggested uses: structural clay products, pottery, drain tile, and flower pots. SAMPLE 1338B NWi Nwi SWi sec. 6, T. 7 S. , R. 5 W. About li miles west of Wine Hill, in south branch of Hornblasted Branch beside road, about 200 feet south of the south- ernmost bridge across Hornblasted Branch. Approximately 9 feet of light brownish gray, well bedded shale; overburden thin. Material: shale Age: Pennsylvanian - Caseyville Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: building blocks and tile, drain tile, and sewerpipe. SAMPLE 1418 NWi NEi sec. 32, T. 7 S. , R. 6 W. About 2 miles southeast of Chester, west cut bank of Chester and Mt. Vernon Railroad and county road in west valley wall of Mary's River, southeast of Illinois Highway 3. About 30 feet of dark gray shale, thinly laminated in lower 20 feet, beds massive and cemented in upper 10 feet. Material: shale Age: Mississippian - Waltersburg Forma- Water of plasticity, percent Linear drying shrinkage, percent 17 Workabil ity : fair 3.12 1832°F 1922°F 2012°F 2.09 4.69 7.25 5.21 7.81 9.37 Chocolate Chocolate Chocolate Age: Mississippian 24 tion 5.21 Workabil ity: good 1832°F 1922°F 0.52 2.08 5.73 7.29 Salmon Red Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: test samples bloated at 2012°F} organic matter high; might be difficult to oxidize Suggested uses: drain tile. RICHLAND COUNTY SAMPLE 1413 NE corner sec. 14, T. 2 N. , R. 10 E. About Tj- miles north of Parkersburg along south-flowing tributary to Sugar Creek, south of unimproved dirt road. Approximately 3 feet of weathered shale exposed. !0 Workabil ity: good 2.60 1832°F 1922°F 1.56 2.61 4.16 5.21 Salmon Salmon CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 55 RICHLAND COUNTY- continued SAMPLE 1413 - continued Material: shale Age: Pennsylvanian - Mattoon Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 1.56 2.61 6.77 Total linear shrinkage, percent 4.16 5.21 9.37 Fired colors Salmon Salmon Red Suggested uses: structural clay products, drain tile, and flower pots. ROCK ISLAND COUNTY SAMPLE J399 NWi SEi SEy sec. 27, T. 17 N., R. 1 W. About 1 mile west of Coal Valley on south cut bank of Coal Valley Creek, south of U. S. Highway 150. Approximately 25 feet of blue-gray shale. Material: shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperature Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: scummed Suggested uses: structural clay products, drain tile, flower pots, and sewerpipe. SAMPLE 1354A SWf SW5- SE^- sec. 6, T. 17 N., R. 5 W. About 2§- miles southeast of Muscatine, Iowa, along north road cut of Illinois Highway 99, on east bluff of Mississippi River. Approximately 30 feet of dark gray, well laminated shale is exposed. Material: shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: ferrous sulfate scumming; unweathered shales should be free of this scumming; organic content would probably make oxidation difficult Suggested uses: building tile and drain tile. ST. CLAIR COUNTY SAMPLE 1329A SWi NWi NWi sec. 21, T. 2 N., R. 8 W. About 2 miles east of French Village, west bank of tributary of Little Canteen Creek. Approximately 16 feet of olive-gray shale grading upward into dark gray shale. 24 Workabi] .ity: good 4.16 1832°F 1922°F 2012°F 3.65 4.17 8.30 7.81 8.33 11.46 Salmon Salmon Red 5 tion - Francis Creek Sha le 3.99 Workabil 1832°F 3.30 7.29 Salmon ity: good 1922°F 5.38 9.37 Salmon 2012°F 7.99 11.98 Red 21 Workabil ity: good 2.34 1832°F 1922°F 201 2° F 2.87 6.51 7.55 5.21 8.85 9.89 Red Red Red 56 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 ST. CLAIR COUNTY- continued SAMPLE 1329A - continued Material: shale Age: Pennsylvanian - Modesto Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: scummed Suggested uses: structural clay products, drain tile, flower pots, and sewerpipe. SAMPLE 1329B Center SWi SWi sec. 21, T. 1 S. , R. 7 W. About 1 mile east of Freeburg, north side of road on east side of stream valley. Ten to 12 feet of gray shale taken from road level to top of shale. Material: shale Age: Pennsylvanian - Modesto Formation Water of plasticity, percent 27 Workability: good Linear drying shrinkage, percent 4.42 Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: overfired at 2012°F Suggested uses: sewerpipe. SAMPLE 1333A NEi SWi sec. 32, T. 2 N., R. 8 W. Hill Brick Company pit about 3 miles east of Edgemont. About 40 feet of sandy shale exposed. Material: shale Age: Pennsylvanian - Modesto Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and flower pots. SAMPLE 1334A NWi NEi sec. 31, T. 2 N. , R. 8 W. Hydraulic Press Brick Company pit about 2 miles east of Edgemont. About 40 feet of blue-gray shale. Material: shale Age: Pennsylvanian - Modesto Formation Water of plasticity, percent 18 Workability: good Linear drying shrinkage, percent 2.34 1832°F 1922°F 2012°F 5.47 9.64 8.60 9.89 14.06 13.02 Salmon Red Brown 20 Workabil ity: good 2.60 1832°F 1922°F 2012°F 2.08 3.65 7.29 4.68 6.25 9.89 Salmon Red Red 1832°F 1922°F 2012°F 2.87 9.43 7.03 5.21 11.77 9.37 Chocolate Chocolate Chocolate Age: F ennsy Lvanian 7 tion 2.08 Workabi llty: fair 1832°F 1922°F 3.13 6.25 5.21 8.33 Salmon Red CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 57 ST. CLAIR COUNTY- continued SAMPLE 1334A - continued Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: overfired at 2012°F Suggested uses: drain tile, building block and tile, and sewerpipe. SALINE COUNTY SAMPLE 1327A SEj- SE5- sec. 21, T. 9 S. , R. 6 E. Harrisburg Brick and Tile Company pit south of Harrisburg. Sample represents lower 8 feet of shale. Material: shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 3.13 6.25 7.81 Total linear shrinkage, percent 5.21 8.33 9.89 Fired colors Salmon Red Red Suggested uses: structural clay products, drain tile, and flower pots. SANGAMON COUNTY SAMPLE 1330 B Sec. 11, T. 15 N., R. 5 W. Springfield Clay Products pit, southeast part of Springfield. Approximately 30 feet of massive blue-gray shale. Material: shale Age: Pennsylvanian - Modesto Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and flower pots. SAMPLE 1332 A SW5- sec. 1, T. 15 N., R. 5 W. Poston Brick and Concrete Products Company pit, southeast part of Springfield. Approximately 35 feet of massive gray shale. Material: shale Age: Pennsylvanian - Modesto Formation Water of plasticity, percent 19 Workability: good Linear drying shrinkage, percent 1.82 Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 0.83 5.99 9.11 Total linear shrinkage, percent 2.65 7.81 10.93 Fired colors Salmon Red Red Suggested uses: structural clay products, drain tile, and flower pots. 19 Workabil ity: good 2.08 1832°F 1922°F 201 2° F 2.09 6.77 8.34 4.17 8.85 10.42 Salmon Salmon Red 58 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 t. in. 4 9 2 4 ± 8 9 1-1* 11-22 1-lf 2 5 SCHUYLER COUNTY SAMPLE R 210 Ng- SWi SWi sec. 8, T. IN., R. 1 E. Sampled in 1931. Pennsylvanian - Carbondale Formation 7. Clay, gray, somewhat sandy, poorly bedded 6. Coal Pennsylvanian - Spoon Formation 5. Clay, gray, poorly bedded 4. Coal 3. Clay, like 5 above 2. Coal 1. Clay, like 5 above Covered Sample R 210 was taken from beds 1, 3, 5, and 7. Characteristics of Unfired Material This clay is a mixture of light and dark grayish materials, with some coaly fragments and concretions. It has a stony fracture. With the addition of 25 percent water, a soft mass having an "oily" feel and rather low plasticity is developed. When this material is dried under ordinary room conditions, it has a linear shrinkage of 6.7 percent and, owing to a soluble sulfate of iron, a reddish scum appears. Its bonding strength of 152 pounds per square inch is low-medium. A moderate reaction occurs when the sample is treated with dilute hydrochloric acid. A residue consisting of particles of pyrite, coaly material, quartz grains bonded with calcium carbonate (?), and some unslaked materials amounting to a total of 24 percent was separated on a 40-mesh sieve. Characteristics of Fired Material Linear shrinkage % Cone Porosity % Color Hardness Burning Total 04 29.3 Light buff 2.2 9.0 01 29.7 Light buff 1.9 8.7 1 28.1 Light buff 2.6 9.4 3 25.6 Light buff 3.5 10.3 6 20.9 Tan Steel hard 5.3 12.1 8 13.6 Gray-tan Steel hard 7.1 13.9 9 8.7 Stoneware c iray Steel hard 7.6 14.4 11 11.3 Stoneware c iray Steel hard 4.9 11.7 14 13.5 Brown fused surface Steel hard 1.4 5.4 Remarks: the clay oxidized readily and vitrified rather slowly with a low or me- dium total shrinkage. The minimum porosity was reached at cone 9 and apparently slight overburning occurred above that point. An unsightly red scum owing to soluble salts appears on the dried pieces and is conspicuous from cone 04 to cone 9. This will interfere with the use of the clay for many purposes. Suggested uses: common brick and hollow ware. SAMPLE R 516 NEi SWi NEi sec. 32, T. 2 N., R. 1 E. Cut along Chicago, Burlington, and Quincy Railroad. Sampled in 1932. Age: Pleistocene. Three and one-half feet of noncalcareous loess in cut; overlain by 14 feet of other unconsolidated materials. CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 59 SCHUYLER COUNTY- continued SAMPLE R 516 - continued Characteristics of Unfired Material Reaction for carbonates: none Hardness: soft; crumbled in fingers Reaction for pyrites: none Working properties: lean; does not weld Color: light brown Water of plasticity, percent: 23.7 Modulus of rupture: 540 lbs. per sq. in. - 11 specimens Fineness Residue, percent: 48-mesh - 0.8 Character of residue: chiefly limonite and some quartz Drying Air shrinkage, plastic basis, percent: 3.4 Dry basis, percent: linear 4.4 volume 12.6 Characteristics of Fired Material Absorp- Linear shrinkage % Cone tion % Color Hardness Burning Total 010 18.1 Salmon 0.6 3.8 07 18.5 Salmon 0.7 3.7 01 9.9 Grayish brown 3.7 8.1) color 3 3.4 Dark brown Steel hard 7.8 12.2) uniform Remarks Drying shrinkage: low (plastic basis) Color range: 0. K. Flexural strength: high-medium; quite Plasticity: poor; doubtful it can be exceptional for such lean material extruded Burning shrinkage: medium at cone 3 Vitrification: slow, porosity cone 3 - 3.4 percent Suggested uses: common brick. SAMPLE 1410 SEi SWi SWi sec. 27, T. 2 N. , R. 2 W. About 2 miles west of Rushville, north cut bank of road in east valley wall qf Harvey Branch. Approximately 20 feet of light blue-gray shale. Material: shale Age: Pennsylvanian - Carbondale Forma- Water of plasticity, percent 18 tion - Francis Creek Shale Linear drying shrinkage, percent 2.08 Workability: fair Fired temperatures 1832°F 1922°F 2012°F Linear fired shrinkage, percent 3.13 3.65 8.91 Total linear shrinkage, percent 5.21 5.73 10.99 Fired colors Salmon Salmon Red Remarks: overfired at 2012°F Suggested uses: structural clay products, drain tile, and flower pots. SCOTT COUNTY SAMPLE R 129 SEi SEi SWi sec. 23, T. 15 N., R. 13 W. Sampled in 1930. ft. in. 3± 4 6 6+ 10-11 2 6 60 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 SCOTT COUNTY- continued SAMPLE R 129 - continued Pennsylvanian - Spoon Formation 5. Limestone, cobbles and boulders 4. Fire clay, medium gray 3. "Coal bloom" 2. Shale, gray and black (sample R 129) 1. Limestone Characteristics of Unfired Material This is a mixture of approximately one-quarter black, soapy and three-quarters gray, sandy clays. The black portion is medium-hard and has a conchoidal fracture. The gray is sandy and hard and has a stony fracture. When 29 percent water is added to the material, it develops a good plasticity. This mass dries moderately rapidly under ordinary conditions and has a linear shrink- age of 9.3 percent, but a considerable scum appears. It has a medium bonding strength with a value of 201 pounds per square inch. The clay is slaked in water and sieved through a 40-mesh sieve; 25 percent of residue is collected, consisting largely of unslaked material with some lignitic particles. The clay burns satisfactorily without any difficulty in oxidation. Characteristics of Fired Material Linear shrinkage % Cone Porosity % Color Hardness Burning Total 05 27.7 Light yellow 3.2 12.5 01 26.8 Light yellow 3.6 12.9 1 26.1 Light yellow 4.1 13.4 2 26.3 Light yellow 4.2 13.5 4 24.7 Yellow Steel hard 4.7 14.0 6 22.9 Light buff Steel hard 5.1 14.4 8 21.6 Light buff Steel hard 5.3 14.6 9 19.0 Light buff Steel hard 6.2 15.5 12 13.8 Tan with black specks Steel hard 7.3 16.6 14 1.7 8.0 17.3 Remarks: this is a refractory clay with a PCE of cone 27. When burned it has a high porosity which is not much decreased until cone 9 is passed. The linear burning shrinkages are low to medium within that range. When a temperature above cone 12 is reached, the clay becomes virtually nonabsorbent. The color varies consistently from a yellow-buff to a tan (at cone 12) but a scum darkens the color above cone 4. Suggested uses: the clay appears best adapted for use for refractories intended for moderate requirements. The presence of the scum lessens its value for many wares. Possibly it may be useful for hollow ware. SHELBY COUNTY SAMPLE 1422 NW cor. sec. 24, T. 11 N. , R. 3 W. About 1 mile southwest of Shelbyville on east road cut in south valley wall of creek. Approximately 6 feet of shale exposed, overburden thin. Material: shale Age: Pennsylvanian - Mattoon Formation Water of plasticity, percent 20 Workability: fair Linear drying shrinkage, percent 2.60 CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 61 SHELBY COUNTY- continued SAMPLE 1422 - continued Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors 1832°F 2.61 5.21 Salmon 1922°F 3.13 5.73 Salmon Suggested uses: structural clay products, drain tile, and flower pots, 2012°F 7.29 9.89 Red STARK COUNTY SAMPLE 1398 NE^ NWj sec. 25, T. 13 N., R. 6 E. About three-fourths of a mile north of Wyoming - , south cut bank of tributary to Spoon River on south side of road. Approximately 8 feet of shale exposed. Material: shale Age: Pennsylvanian - Carbondale Forma- Water of plasticity, percent Linear drying shrinkage, percent Fired temperature Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: overburned at 2012°F Suggested uses: structural clay products, drain tile, and flower pots. 19 tion 2.56 Workabil ity: fair 1832°F 1922°F 0.56 1.08 3.12 3.64 Salmon Salmon 2012°F 6.81 9.37 Red TAZEWELL COUNTY SAMPLE R 220 Ng- N£ sec. 5, T. 25 N. , R. 4 W. Sampled in 1931. Carbondale Formation. Age: Pennsylvanian 4. Glacial clay overburden 3. Shale 2. Clay, calcareous 1. Shale, gray, with scattered ferruginous concretions (sample R 220) Covered Characteristics of Unfired Material ft. 2 7 13 in. 6 The material is a mixture of fairly hard, a hackly to conchoidal fracture, with a sandy s mixture has fair plasticity over a moderate ran to develop a normal, good working consistency, indicated by a modulus of rupture of 134 pounds It dries slowly without difficulty under o has a shrinkage of 6.4 percent. When slaked and washed on a 40-mesh sieve, consists of unslaked original material, some mi and bonded into aggregates. Treatment with hot hydrochloric acid cause the presence of carbonates. When burned, the c uniformly gray shale, and it has hale having a stony fracture. The ge, and requires 27.6 percent water A low-medium bonding strength is per square inch, rdinary atmospheric conditions and 10.8 percent residue remains which ca, and some pyrite in small grains s mild evolution of gas, indicating lay oxidizes readily. 62 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 TAZEWELL COUNTY- continued SAMPLE R 220 - continued Characteristics of Fired Material Linear shrinkage % Cone Porosity % Color Hardness Burning Total 07 18.1 Salmon 6.1 12.5' 02 0.3 Reddish brown Steel hard 10.4 16.8 2 0.3 Reddish brown Steel hard 10.0 16.4 3 0.3 Brown Steel hard 9.0 15.4 6 0.4 Black-brown, glazed and rough Steel hard 8.0 14.4 Remarks: the material is well vitrified at cone 02 and does not show definite overburning until cone 3 is passed. The total shrinkages are high. The product is hard and has a satisfactory uniformly even color from cone 02 upwards. Some small particles of iron pyrites are present. Suggested uses: sewer brick, tile, and hollow ware. SAMPLE 1322B NWi NEi sec. 5, T. 25 N., R. 4 W. Peoria Brick and Tile Company pit, south of East Peoria. Sample taken from shale bin. Material: shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Age: Pennsylvanian - 19 tion 2.60 Workability: good 1832°F 1922°F 2.08 4.69 4.68 7.29 Salmon Salmon Carbondale Forma- 2012°F 5.73 8.33 Red Suggested uses: structural clay products, drain tile, and flower pots. UNION COUNTY SAMPLE 1335A NEi SWi NEi sec. 11, T. 13 S., R. 2 W. About 3g- miles southwest of Jones- boro; cut in southeast bank of creek along west fork of road. Approximately 50 feet of pinkish brown to tan to maroon to light gray, massive to poorly bedded and to thinly bedded shale; top more silty than bottom. Material : shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors 25 Workability: fair 3.12 1832°F 1922°F 2012°F 1.56 5.73 10.42 4.68 8.85 13.54 Light salmon Salmon Red Suggested uses: structural clay products, drain tile, flower pots, and sewerpipe. CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 63 VERMILION COUNTY SAMPLE 1343A 12 W. Harmattan Mine of Fairview Collieries about 1 Eg- sec. 4, T. 19 N., R mile west of Hillery. Lower 10 feet of blue-gray shale Material : shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: considerably overfired at 2012°F Suggested uses: sewerpipe and structural clay products. Age: Pe nnsy] .vanian 20 Farmin gton Shale 2.77 Workabil ity: fair 1832°F 1922°F 6.61 8.69 9.38 11.46 Salmon Red Modesto Formation 2012°F SAMPLE 1343B Same location as sample 1343A. Upper 10 feet of weathered shale. Material : shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors 2.60 Age: Pennsylvanian - Modesto Format ii Farmington Shale Workability: fair 1832°F 1922°F 2012°F 3.65 4.17 5.21 6.25 6.77 7.81 Salmon Salmon Red Remarks: scumming; overfired at 2012°F Suggested uses: structural clay products, drain tile, and flower pots. SAMPLE 1342A NWi NE^ sec. 14, T. 19 N. , R. 12 W. Western Brick Company pit, about 1 mile southeast of Batestown. About 25 feet of shale. Age: Pennsylvanian - Modesto Formation - Material: shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: overfired at 2012°F Suggested uses: structural clay products, drain tile, and flower pots. 22 Farmington Shale 2.62 Workabi lity: good 1832°F 1922°F 2012' 3.11 6.76 6.76 5.73 8.33 9.38 Salmon Red Red WARREN COUNTY SAMPLE NF 378 NEi SWi NWi sec. 14, T. 9 N. , R. 1 W. Sampled in 1935. 64 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 WARREN COUNTY- continued SAMPLE NF 378 - continued Section exposed on the north side of Cedar Creek: Covered Pennsylvanian - Spoon Formation 4. Coal 3. Shale or clay (sample NF 378) 2. Coal blossom 1. Chert, rubble from Burlington (Mississippian) Limestone Covered Characteristics of Unfired Material ft. 10-15 1 + 6 2-4 4 Color: light gray; some dark gray inter- mixed Hardness: most crumbles readily between the fingers, but part is hard and shaly Reaction for carbonates: cold - negative hot - negative Fracture: most of it has a granular fracture; some has a fissile fracture Screen test: residue on 35-mesh screen - 0.25 percent; 90 percent sandstone, quartz, and root casts, and some limonite and roots Characteristics of Fired Material Reaction for pyrite: negative Soluble salts: sulfates feeble Working properties: very good Drying shrinkage, percent: linear 8.1 volume 26.2 easy to dry Drying conduct Absorp- Por- Burning tion % osity % Color Hard- ness shrin kaqe % Cone Linear Volume Remarks 06 16.7 29.3 Peach 3 1.2 3.6 2 4.2 9.4 Light tan 8 9.0 24.6 Slightly scummed on edges 3 7.3 Light buff 8 9.1 24.7 6 0.15 0.3 Greenish buff 9 10.7 28.7 Tends to warp slightly during vitrification Oxidation conduct: requires moderately long oxidation period Soluble salts: sulfates trace Warpage: tends to warp slightly during vitrification Suggested uses: buff face brick, stoneware, and terra cotta. SAMPLE NF 377 Center W§- NWi sec. 10, T. 9 N., R. 2 W. Sampled in 1935. Age: Section exposed in south bank of Cedar Creek east of the road: Covered Pennsylvanian - Spoon Formation 7. Sandstone, fine-grained, thin-bedded 6. Coal (Wiley Coal?) 5. Underclay, gray 4. Coal 3. Underclay, gray 2. Limestone, dark gray, dense 1. Clay, cream (sample NF 377) Pennsylvanian. ft. in. 20-30 2 5 4 2+ 6 2-4 0-8 CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 65 WARREN COUNTY- continued SAMPLE NF 377 - continued Characteristics of Unfired Material Color: gray Hardness: medium Fracture: irregular Reaction for carbonates: cold - negative hot - negative Reaction for pyrite: negative Working properties: good Drying shrinkage, percent: linear 8.2 volume 26.8 Drying conduct : good Screen test: residue on 35-mesh screen - 0.11 percent; brown, red, white, gray, and black sandstone; considerable gritty material passed 35-mesh Characteristics of Fired Material Burning shrinkage Cone Absorption % Porosity % Color Hardness Linear Volume 06 19.9 33.3 Pinkish white 3 1.8 5.3 3 11.8 22.6 Light cream 5 4.9 13.9 7 4.5 9.9 Gray to tan 8 9.1 25.0 Oxidation conduct: no difficulty Soluble salts: none detected Suggested uses: face brick, common brick, stoneware, or conduits. SAMPLE NF 376 NE^- NWi NEi sec. 35, T. 12 N. , R. 3 W. Sampled in 1935. Age: Mississippian Kinderhook Shale. The sample, taken from 4 feet of greenish brown shale, was exposed in a gully. The shale occurs in the upper part of the Kinderhook Formation. Characteristics of Unfired Material Color: yellow buff Soluble salts: sulfates - small amount Hardness: lg-j unshattered by fingers Working properties: excellent Fracture: angular to conchoidal Drying shrinkage, percent: linear 8.9 Reaction for carbonates: cold - strong volume 29.2 hot - trace Drying conduct: good; no difficulty Reaction for pyrite: negative noted Screen test: residue on 35-mesh screen - 5.0 percent; limestone pebbles and some limonite Characteristics of Fired Material Absorp- Por- Burning tion osity Hard- shrinkage % Cone % % Color ness Linear Volume Remarks 06 23.0 37.0 Salmon 4 02 22.0 36.0 Light buff 5 2 21.0 34.5 Light tan 6 6 0.5 1.2 Chocolate brown 9 1.0 3.1 Several lime pops 1.1 3.3 Cream spots; traces of s c urn 1.8 5.3 Trace of scum; one iron pop 9.5 25.8 Pretty well vitrified; would soon fuse Oxidation conduct: satisfactory Soluble salts: trace Warpage: none Suggested uses: face brick, hollow tile, and common brick. 66 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 WASHINGTON COUNTY SAMPLE 1339A SEi SWi SWi sec. 18, T. 2 S. , R. 4 W. About 7^ miles east of St. Libory, roadcut west side of Elkhorn Creek. Approximately 12g- feet of olive-gray, clayey, fairly well bedded shale with plant fossils and ironstone concretions. Material: shale Age: Pennsylvanian - Modesto Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products, drain tile, and sewerpipe. WHITE COUNTY SAMPLE 1409 NWi SWi SWi sec. 11, T. 5 S. , R. 9 E. About 1 mile northwest of Carmi, about 200 yards east of road on south bank of Big Hill Branch. Approximately 8 feet of dark gray shale exposed. 24 Workabil ity: fair 3.90 1832°F 1922°F 2012°F 4.95 7.03 7.56 8.85 10.93 11.46 Salmon Red Red Material : shale Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: poor workability, scumming, oxidization difficulties. Mattoon Formation 7 1.04 Workabil ity: poor 1832°F 3.12 4.16 Salmon 1922°F 3.65 4.69 Salmon 2012°F 9.38 10.42 Brown WHITESIDE COUNTY SAMPLE NF 411 Center W line, NWi sec. 3, T. 22 N. , R. 4 E. Sampled in 1938. Age: Penn- sylvanian? The sample from 2 feet of gray clay - in places blotched purple, pink, and green - exposed in roadcut. The clay rests on Niagaran dolomite and contains scattered masses of rotted dolomite. It is not clear whether the clay is a residu- um from the weathering of dolomite or is slumped from a higher deposit and the rotted dolomite incorporated during the process. Dolomite was excluded from the clay sam- pled. Characteristics of Unfired Material Color: gray with faint greenish cast Hardness: breakable by hand with difficulty Fracture: tends to break into angular fragments Reaction for carbonates: cold - none hot - none Reaction for pyrite: not detected Soluble salts: sulfates present Working properties: very good Water of plasticity, percent: 25.6 Shrinkage water, percent: 13.9 Pore water, percent: 11.7 CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 67 WHITESIDE COUNTY- continued SAMPLE NF 411 - continued Slaking time: 100 percent clay - 19j- minutes; 50 percent clay— 50 percent flint - 70 minutes Drying shrinkage, percent: linear 8.0; volume 26.1 Drying conduct: excellent; no tendency to warp or crack noted; a little scum was noted on the drying bars, but it could not be seen on the fired bars Modulus of rupture: dry clay - 418 lbs. per sq. in. - 12 specimens; with 50 per- cent standard sand - 226 lbs. per sq. in. - 15 specimens Screen test: Residue on Percent Character of residue 10-mesh 0.10 Quartz grains cemented with clay; limo- nite replacing wood 20-mesh 0.16 Quartz grains cemented with clay; trace of limonite; some lignite 35-mesh 0.75 Same as on 20-mesh 65-mesh 1.60 Clean, clear quartz grains; some limo- nite; some lignite 100-mesh 0.88 Same as on 65-mesh 150-mesh 0.80 Same as on 65-mesh 200-mesh 0.93 Clear, white quartz sand; some lignite; some biotite Characteristics of Fired Material Absorp- Por- Bur ning Total tion % osity % Color Hard- ness shrin Linear kage % Volume shrin ikage % Cone Linear Volume Oil 16.2 29.3 Light cream 2 1.5 4.3 9.5 30.4 06 15.2 26.0 Gray-white 3 3.3 9.7 11.3 35.8 02 11.7 20.1 Poor white 7 5.1 14.5 13.1 30.6 4 6.2 13.6 Poor white 8 7.7 21.3 15.7 47.4 7 3.6 7.9 Poor white 9 9.7 26.3 17.7 52.4 9 1.1 2.7 Gray-white 9 9.9 26.9 17.9 53.0 Oxidation conduct: easy to oxidize PCE value (fusion test): cone 32 Warpage: none noted Remarks: a plastic fire clay of exceptional white color, the material is not an open-burning clay, but becomes vitrified at about cone 9, and presumably has a fairly long vitrifying range. Classed as No. 2 fire clay because of its vitrify- ing characteristics and because of its high PCE (cone 32), the clay also possesses the characteristics of a refractory bond clay and a ball clay, both of which are usually No. 2 fire clays. The color is good and it is fairly well vitrified at cone 9, but the dry strength is not very high. It has good forming, drying, and firing characteristics. Suggested uses: the clay can be used as a bond clay for refractories, saggers, glass pots, crucibles and, in some cases, as a ball clay. It would be especially useful as a bond clay of rather low iron content and fairly high maturing tem- peratures, for example, some glass house refractories. It would be useful for face brick, terra cotta, and some types of pottery. 68 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 WILL COUNTY SAMPLE NF 396 NWi SWi SWi sec. 30, T. 33 N. , R. 9 E. Sampled in 1936. Age: Pennsylvanian - Spoon Formation. The sample is taken from a 4-foot cut in the underclay of Colchester (No. 2) Coal in the floor of a pit of Northern Illinois Coal Corporation. Characteristics of Unfired Material Color: gray, streaks of black, carbona- Working properties, manual: very ceous material plastic Hardness: fairly hard Drying shrinkage, percent: linear 6.71 Fracture: irregular volume 18.66 Reaction for carbonates: cold - very Drying conduct: good; no warping; no slight noticeable scum Screen test: residue on 35-mesh - 1.35 percent; silica; black and brown carbona- ceous material Characteristics of Fired Material Absorp- Burning tion % Color Hard- ness shrin kage % Cone Linear Volume Remarks Bright 06 14.35 orange-red 2 0.72 0.57 Trace of scum 02 7.63 Brown-red 6 4.05 8.63 Trace of scum 4 0.60 Chocolate brown 8 5.71 15.54 No scum; slight overf iring Oxidation conduct: good; complete in heating-up period Remarks: color not of good grade for face brick; lacks redness and brilliance. High plasticity and drying shrinkage might cause some trouble in manufacturing. Firing behavior is satisfactory, and the material matures between cones 02 and 1 but does not readily overfire. Suggested uses: common brick, building tile, and drain tile. SAMPLE PS 96 Center SE?- sec. 32, T. 33 N., R. 9 E. In pit of Northern Illinois Coal Cor- poration. Sampled in 1931. Age: Pennsylvanian - Carbondale Formation - Francis Creek Shale. The strata exposed are: ft. in. 3. Soil, sandy, black 1 6 2. Sand and gravel 3 1. Shale, gray, slightly gritty, containing concretions (sample DS 96) 33 Covered Characteristics of Unfired Material Color: light gray Drying shrinkage, percent: linear 5.28 Hardness: soft volume 15.27 Fracture: smooth to crumbly Drying conduct: good; no tendency to Reaction for carbonates: cold, very warp; no noticeable scum slight Screen test: residue on 35-mesh screen - Working properties: manual - very 0.334 percent; mainly silica plastic; rubbery CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 69 Cone WILL COUNTY- continued SAMPLE DS 96 - continued Characteristics of Fired Material Absorp- tion % Color Burning Hard- shrinkage % ness Linear Volume Remarks 06 15.75 Pink-red 3 2.81 8.49 02 6.02 Pale red 7 7.73 22.17 4 0.10 Dark chocolate 9 10.53 30.33 brown Considerable scum Considerable scum No scum; much overfired Oxidation conduct: oxidized readily in heating-up period Remarks: material has a fair color in firing but is lacking in brilliance or intensity of the red color. Both drying and firing shrinkages are rather high. Maturing in firing occurs between cones 02 and 1, and overfiring is evident at cone 4 or lower. Suggested uses: common brick, building tile, and drain tile. SAMPLE NF '389 East line, NE^ SWi NEi sec. 16, T. 34 N., R. 9 E. Sampled in 1936. Age: Ordovician - Maquoketa Shale. Shale exposed in a cut along west side of road in the lower part of the north slope of a hill: 3. Earth 2. Siltstone, brown} limestone, dolomite, and clay 1. Siltstone, greenish, calcareous, thin-bedded, shaly with local hard layers (sample NF 389 from several 6-foot exposures of bed l) Covered Characteristics of Unfired Material ft. 1-2 4-6 Color: green Hardness : fairly hard Fracture: conchoidal Reaction for carbonates: cold erable Working properties, manual Drying shrinkage, percent: consid- very plastic linear 5.86 volume 23.22 Drying conduct: no warping; no visible scum Screen test: residue on 35-mesh - 2.69 percent; silica; green transparent par- ticles, iron compounds Characteristics of Fired Material Absorp- Burning tion % Color Hard- ness shrin kage % Cone Linear Volume Remarks 06 10.55 Light brownish red 7 0.71 12.17 Very slight scum 02 0.15 Brownish red 7 8.77 26.12 Very slight scum 4 0.0 Light choco- late brown 8 9.25 27.15 No scum; slight overfiring 2 Workabil ity: poor 2.60 1832°F 1922°F 2012°F 5.73 4.69 6.77 8.33 7.29 9.37 Salmon Salmon Red 70 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 WILL COUNTY- continued SAMPLE NF 389 - continued Remarks: color not satisfactory for good red ware at any point in firing range; at the maturing range, about cone 02, brown is predominant. The drying and firing shrinkages are rather high, requiring some care in drying and firing, but otherwise the properties are satisfactory. Suggested uses: common brick, building tile, and drain tile. WILLIAMSON COUNTY SAMPLE 1419 Sg- Njj- sec. 21, T. 9 S. , R. 4 E. Delta Mine of Carmi Coal Company, about 2 miles east of Craborchard. Approximately 20 feet of blue-gray shale. Material: shale Age: Pennsylvanian - Carbondale Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Remarks: overfired at 2012°F Suggested uses: structural clay products, drain tile, and flower pots. SAMPLE 1417 SE-f SE^- sec. 25, T. 10 S. , R. 3 E. About one-half mile east of Creal Springs, east face of old stone quarry. About 3 feet of gray clay. Material: underclay Age: Pennsylvanian - Spoon Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: pottery, structural clay products, and sewerpipe. SAMPLE 1429 Same location as sample 1417 but below that sample. Approximately 6 feet of gray shale. Material: shale Age: Pennsylvanian - Spoon Formation Water of plasticity, percent Linear drying shrinkage, percent Fired temperatures Linear fired shrinkage, percent Total linear shrinkage, percent Fired colors Suggested uses: structural clay products and drain tile. 5 Workabil ity: good 3.12 1832°F 1922°F 2012°F 1.56 1.56 5.21 4.68 4.68 8.33 Cream Cream Cream 22 Workabil ity: fair 2.60 1832°F 1922°F 2012°F 1.04 2.61 6.78 3.64 5.21 9.38 Buff Buff Brown CERAMIC TESTS OF ILLINOIS CLAYS AND SHALES 71 COOK COUNTY SAMPLE NF 230 NWi NEi SEi sec. 11, T. 36 N., R. 12 E. Sampled in 1934 from a roadcut; the material is a clay deposited in ancient Orland Lake in front of the Tinley end moraine. Age: Pleistocene - Wisconsinan. The beds exposed are: ft_. in. 3. Soil ,6 2. Clay and soil mixed 1 6 1. Clay, gray and brown, calcareous, locally slightly laminated (sample NF 230) 7 Covered Characteristics of Unfired Material Material: Orland Lake clay Friability: easily crumbled; can be Reaction for carbonates: yes powdered between the fingers Reaction for pyrites: no Working properties: excellent Color: light buff, yellowish tint Water of plasticity, percent: 28.6 Soluble salts: sulfates present Shrinkage water, percent: 13.2 Drying shrinkage, percent: linear 7.4 Pore water, percent: 15.4 volume 24.1 Slaking time: 100 percent clay - 15 Drying conduct: satisfactory; slight minutes; 50 percent clay — 50 percent tendency to crack if dried too rapidly flint - 4 minutes, 30 seconds Modulus of rupture Lbs. per sq. in. No. of specimens Dry clay 801 14 With 50 percent standard sand 196 13 Screen test: Residue on Percent Character of residue 10-mesh 0.69 Limestone and sandstone 20-mesh 0.93 Limestone, sandstone, and quartz 35-mesh 0.19 Limestone, sandstone, roots quartz, and a few 65-mesh 0.15 Calcite and quartz 100-mesh 0.05 Calcite and quartz 150-mesh 0.09 Calcite and quartz 200-mesh 0.16 Calcite and quartz Charact eri St ics of Fired Material Absorp- Por Burning Total tion osity % Col or Hard- shrinkage % shrinkage % Cone % ness Linear Volume Linear Volume Oil 14.4 35.8 Salmon 3 0.84 2.5 8.30 26.6 06 13.1 32.5 Salmon 3 1.22 3.6 8.68 27.7 02 10.8 20.4 Reddish 7 5.80 16.4 13.26 40.5 buff 2 4.9 10.5 Red 8 9.43 25.7 16.89 49.8 3 2.4 5.1 - - 12.37 32.7 19.83 56.8 4 0.1 0.3 Greenish 9 14.36 37.2 21.82 61.3 brown Melts 72 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 303 COOK COUNTY- continued SAMPLE NF 230 - continued Oxidation conduct: easy to oxidize Soluble salts: slight scumming PCE value (fusion test): cone 5; cones made from this clay do not bend but they squat or melt suddenly Warpage: no tendency to warp Remarks: nonrefractory, burns to a buff or light red (dependent on atmosphere of kiln). In highly oxidizing atmospheres, good reds can be produced. The clay has a very short maturing range; if fired above cone 4 it melts. Limestone particles cause the burned clay to be freckled with cream-colored spots that develop lime pops in cases where the clay has not been exceptionally hard burned. Suggested uses: common brick and drain tile. Illinois State Geological Survey Circular 303 72 p., 1 fig., 1960 llMI-t-IPJ | £and ofjttncofa/ IF CIRCULAR 303 ILLINOIS STATE GEOLOGICAL SURVEY URBANA