s 14.GS: RPI57 c. 3 STATE OF ILLINOIS HENRY HORNER, Governor DEPARTMENT OF REGISTRATION AND EDUCATION JOHN J. HALLIHAN, Director DIVISION OF THE STATE GEOLOGICAL SURVEY M. M. LEIGH TON, Chief URBANA REPORT OF INVESTIGATIONS — NO. 57 FINE-GRAINED MOLDING SAND RESOURCES OF NORTHERN ILLINOIS A Preliminary Investigation BY H. B. WiLLMAN ^^^^X^^js^ PRINTED BY AUTHORITY OF THE STATE OF ILLINOIS URBANA, ILLINOIS 1939 STATE OF ILLINOIS Hon. Henry Horner, Governor DEPARTMENT OF REGISTRATION AND EDUCATION Hon. John J. Hallihan, Director BOARD OF NATURAL RESOURCES AND CONSERVATION Hon. John J. Hallihan, Chairman Edson S. Bastin, Ph.D., Geology Henry C. Cowles, Ph.D., D.Sc, William A. Noyes, Ph.D., LL.D., Chem.D., Forestry D.Sc Chemistry Arthur Cutts Willard, D.Engr., Louis R. Howson, C.E., Engineering LL.D., President of the University of William Trelease, D.Sc, LL.D., Biology Illinois Enid Townley, M.S., Assistant to the Chief GEOLOGICAL RESOURCES Coal G. H. Cady, Ph.D., Senior Geologist L. C. McCabe, Ph.D. James M. Schopf, Ph.D. Earle F. Taylor, M.S. Charles C. Boley, M.S. Industrial Minerals J. E. Lamar, B.S. H. B. WiLLMAN, Ph.D. Robert M. Grogan, M.S. J. S. Templeton, A.B. Oil and Gas A. H. Bell, Ph.D. G. V. COHEE, Ph.D. Frederick Squires, B.S. Charles W. Carter, Ph.D. F. C. MacKnight, Ph.D. James L. Carlton, B.S. Frank E. Tippie, B.S. Roy B. Ralston, B.A. Areal and Engineering Geology George E. Ekblaw, Ph.D. Richard F. Fisher, B.A. Subsurface Geology L. E. Workman, M.S. J. Norman Payne, Ph.D. Elwood Atherton, Ph.D. Merlyn B. Buhle, M.S. Gordon Prescott, B.S. Stratigraphy and Paleontology J. Marvin Weller, Ph.D. Chalmer L. Cooper, M.S. Petrography Ralph E. Grim, Ph.D. Richards A. Rowland, Ph.D. Physics R. J. Piersol, Ph.D. M. C. Watson, Ph.D. Donald O. Holland, M.S. STATE GEOLOGICAL SURVEY DIVISION Urbana M. M. Leighton, Ph.D., Chief Jane Titcomb M.A., Geological Assistant GEOCHEMISTRY Frank H. Reed, Ph.D., Chief Chemist W. F. Bradley, Ph.D. G. C. Finger, Ph.D. Helen F. Austin, B.S. Fuels G. R. Yohe, Ph.D. Carl Harman, B.S. I Non-Fuels J. S. Machin, Ph.D. James F. Vanecek, M.S. Analytical O. W. Rees, Ph.D. George W. Land, B.P^d. P. W. Henline, B.S. Mathew Kalinowski, B.S. A. J. Veraguth, M.S. MINERAL ECONOMICS W. H. VosKuiL, Ph.D., Mineral Economist Grace N. Oliver, A.B. EDUCATION EXTENSION Don L. Carroll, B.S. PUBLICATIONS AND RECORDS George E. Ekblaw, Ph.D. Chalmer L. Cooper, M.S. Dorothy Rose, B.S. Alma R. Sweeney, A.B. M. Frances Harper, M.S. Meredith M. Calkins Consultants: Ceramics^ Cullen Warner Parmelee, M.S., D.Sc, University of Ilhnois; Pleistocene Invertebrate Paleontology, Frank Collins Baker, B.S., University of Illinois. Topographic Mapping in Cooperation with the United States Geological Survey. This Report is a Contribution of the Section of Geological Resources, Division of Industrial Minerals. °^^2 August 1, 1939 SURVEY LIBRARY (A4192) CONTENTS Page Summary 5 Introduction 6 Procedure 6 Acknowledgments 7 Character of fine-grained molding sands 7 Albany sand 7 Southern Indiana sand 14 Character of northern Illinois sands 15 Distribution 15 Origin 15 Mineral composition 16 Grain size 17 Permeability 17 Strength 17 Durability 19 Uniformity 19 Blending and processing 19 Uses of fine-grained molding sands 20 Northern Illinois deposits 21 General Statement 21 Albany type sands 24 Promising deposits 24 Albany type No. 00 grade 24 Deposit near Rice, Jo Daviess County 24 Deposit at Round Grove, Whiteside County 26 Deposit near Denrock, Whiteside County 27 Albany type No. Grade 27 Deposit at Aiken, Jo Daviess County 27 Deposit near Milan, Rock Island County 28 Deposit near Lyndon, Whiteside County 29 Deposit near Denrock, Whiteside County 30 Deposit near Morrison, Whiteside County 33 Deposit near Union Grove, Whiteside County 33 Albany type No. 1 Grade 33 Deposit at Lansing, Cook County 33 Deposit near Colona, Henry County 36 Deposit near Aiken, Jo Daviess County 36 Deposit near Mason City, Mason County 37 Deposit near Garden Plain, Whiteside County 38 Deposit near Fenton, Whiteside County 39 Deposit at Round Grove, Whiteside County 40 Other deposits 40 Cook County 41 Ford, Grundy, Iroquois, Kankakee, and Will counties 41 Henry County 42 Jo Daviess County 42 Mason County 42 Rock Island County 42 Winnebago County 43 Southern Indiana type sand 43 Promising deposits 43 Other deposits 45 TABLES Page 1. Variation in grain size of Albany sand by grades 8 2. Average sieve analyses of Albany sand by grades 9 3. Tests of Albany, New York, sands 10 4. Tests of Southern Indiana and similar sands 12 5. Amount of ferric oxide in molding sands 16 6. Samples of northern Illinois sands listed by grain fineness numbers 18 7. Tests of sands used for aluminum, brass, and bronze castings 20 8. Properties of sands used for aluminum and brass castings 22 9. Tests of Albany type sands from northern Illinois 24 10. Average analyses of samples from terrace south of Aiken 37 11. Tests of Southern Indiana type sands from northern Illinois 44 12. Previous tests of fine-grained molding sands from northern Illinois 46 13. Descriptions and sieve analyses of samples from northern Illinois 48 ILLUSTRATIONS Figure Page 1. Distribution of samples by counties 21 2. Locations of samples collected near Rice and Aiken in Jo Daviess County 23 3. Locations of samples collected in western Whiteside County 28 4. Locations of samples collected near Lansing in Cook County 32 5. Locations of samples collected near Mason City in Mason County 38 FINE-GRAINED MOLDING SAND RESOURCES OF NORTHERN ILLINOIS A PRELIMINARY INVESTIGATION BY H, B. WiLLMAN SUMMARY Large quantities of fine-grained molding sand are used annually in the Chicago area in the manufacture of nonferrous, malleable, and small gray-iron castings. Most of this sand is produced at a considerable distance from Chicago. This report gives the results of a preliminary investigation to determine whether or not deposits of suitable sands more favorably located with reference to the Chicago market could be found in northern Illinois. The sands which it was hoped to duplicate in Illinois are of two principal types : (1) Albany, New York, sand, especially grades 00, 0, and 1. These sands have grain fineness numbers between 150 and 250. The coarsest usually do not contain more than 10 per cent of grains coarser than a 70-mesh sieve, and the finest do not contain more than 50 per cent of pan material. (2) Sands w4th grain fineness numbers of 250 to 300 and containing 60 to 85 per cent of pan material. These sands are pro- duced together with other grades of sand in southern Indiana, northern Kentucky, and central and northern Ohio. Sand of this grain size has no general name and for con- venience is referred to in this report as the Southern Indiana sand. Illinois deposits of sand, similar in grain size to the Albany sands, were found near Morrison, Lyndon, Denrock, Fenton, and Garden Plain in Whiteside County; near Aiken and Rice in Jo Daviess County ; near Mason City in Mason County ; near Colona in Henry County; and near Milan in Rock Island County. One deposit near Lansing in Cook County is a possible source of fine- grained molding sand although it does not have the same grain-size distribution as the Albany sand. The most promising deposits of sand sim- ilar to the Southern Indiana sand were found near the Mississippi River blufts in Rock Island, Whiteside, Carroll, and Jo Daviess counties. Sieve analyses are given of numerous samples from deposits in Ford, Grundy, Iro- quois, Kankakee, and Will counties. The samples represent the finest grained sands found in these counties but they are all coarser grained than the Albany No. 1 sands. Numerous deposits were also examined in Bureau, Kane, La Salle, Lee, McHenry, Marshall, Ogle, Peoria, Tazewell, and Winnebago counties. Sieve analyses are reported on 138 of the samples taken during this investigation. Of the samples 42 have grain fineness numbers within the range of the Albany No. 00 to No. 1 sands, and 37 have grain fineness numbers within the range of the Southern Indiana sands. Many of these, how^ever, are unlike the Albany or Southern Indiana sands in distribution of grain size or in clay con- tent. Of the most promising deposits, 12 of the Albany type and 3 of the Southern Indi- ana type of sand were selected for more de- tailed studies. In green compression and permeability several of the samples are in close agreement with the Albany and South- ern Indiana sands. Mineralogical examinations indicate that the Illinois sands are similar to the Albany and Southern Indiana sands in consisting largely of angular and subangular grains of quartz. Microscopic and X-ray studies of representative samples show that the clay minerals in all three sands consist largely of the clay mineral illite. However, some difference apparently exists in the variety of illite, and this may account for the compara- tively high green compressive strengths ob- tained on some of the samples of Illinois sands. [5] FINE-GRAINED MOLDING SAND INTRODUCTION Large quantities of fine-grained molding sands are used in Illinois, particularly^ in the Chicago area, in the manufacture of non- ferrous, malleable, and small gray-iron cast- ings. Most of this sand is produced a long distance from Chicago. The principal source is the Albany, New York, district, but fine- grained sand is also shipped to Chicago from southern Indiana, Ohio, Kentucky, and Tennessee. The value of the Albany sand used yearly in the Chicago district has been variously estimated ; some estimates are as high as $500,000. The price of the Albany sand in Chicago is about $12.00 per ton in small lots from supply houses or about $6.25 per ton in carload lots. Molding sand is relatively low priced. In 1936 the price of molding sand produced in the United States averaged about $1.00 per ton at the pit,^ but some sands, such as the Albany molding sands, command a price higher than the average. The price of the Albany sand at Albany in 1938 was about $2.00 per ton. When molding sand is shipped any great distance, the cost of transportation is a major part of the delivered price. The rail distance from Chicago to Albany is about 800 miles, whereas the maximum distance from Chi- cago to any sand deposits described in this report is about 180 miles and many deposits are closer. The freight rate for Albany sand from Albany to Chicago is $4.29 per ton in carload shipments. This affords any suitable Illinois sands a substantial freight differen- tial over the eastern sands and might permit processing or blending of Illinois sands with- out removing them from a competitive price position. The rail distance from Chicago to Evans- ville, Indiana, is about 285 miles, which gives the northern Illinois sands an advan- tage of 100 miles or more over the southern Indiana sands. As any fine-grained molding sand in northern Illinois would have an advanta- geous location with reference to the Chicago market, an exploratory investigation was made to locate possible deposits of sands of this type and to obtain preliminary data re- garding their probable extent and character. 'Hughes, H. H., and Egge, G., Sand and gravel: U. S. Bur. Mines Minerals Yearbook, 1938, p. 1070. The results of the study are given in this report. Several sands were found which are sim- ilar to the sands now used. Their com- mercial exploitation is not recommended, however, until the deposits have been thor- oughly explored to determine their size and the character of the sand, its possible uses, and potential markets. The emphasis in this investigation was directed primarily toward the discovery of deposits of sand similar in grain size to the Albany and Southern Indiana sands. How- ever, the increasing use of synthetic molding sands suggests that other types of fine-grained sands may be of potential value for the prep- aration of such synthetic sands by washing, screening, or crushing, or by blending with other sands. The comparative scarcity of fine-grained sands suitable for use in syn- thetic mixtures in part accounts for the fact that synthetic molding sands have not re- placed more extensively the natural fine- grained molding sands. Deposits representative of all the various major classes of fine-grained sand deposits in northern Illinois are believed to be included in this report although it was not possible to cover all individual deposits. The report, therefore, serves as a basis for more detailed work in any area wherein the location of additional deposits is of special interest. Procedure The search for fine-grained molding sands in northern Illinois involved, first, the use of the general fund of geologic knowl- edge which the Survey has accumulated re- garding the distribution and character of sand deposits and, second, a search for sand deposits the origin of which was similar to that of the Albany and Southern Indiana sands. The Albany sands are known to have been deposited in a large lake which occupied Hudson River valley in Glacial time. There- fore, many of the areas of Illinois which were also occupied by lakes during Glacial time were examined for similar deposits, as well as many of the terrace areas along rivers which during Glacial time were swollen to the proportions of lakes. The fine-grained Southern Indiana mold- ing sand is probably mostly "loess," which is wind-deposited silt. Material of similar composition and texture also may be laid ALBANY SAND 7 down in lakes or in the slack waters of rivers, and some of the Southern Indiana sand may be of this origin. The similarity of the Southern Indiana sand to loess suggested that the loess deposits of northwestern Illi- nois might be a source of similar materials, particularly the sandy loess near the major valleys. The field work included the examination of outcrops in road cuts and along streams, supplemented by auger borings in some of the more favorable areas where there were no outcrops. As the study was only prelim- inary, specific deposits were not examined in detail. Although not all of the many areas of lake deposits were studied, enough data were collected to indicate the general char- acter of the fine-grained sands in northern Illinois. Samples of about 5 pounds w^re taken from the outcrops or auger borings and were brought into the laboratory where the grain size of the sand was determined according to the methods of the American Foundrymen's Association. Tests were made on 138 sam- ples. On the basis of the grain-size data on the small samples, together with information regarding the probable size, uniformity, and availability of the deposits, 15 deposits were selected as being the most promising. These 15 deposits were revisited and representative samples of about 50 pounds were collected. The large samples were tested for grain fineness, clay content, green compressive strength, and green permeability. The same tests were made on samples of Albany No. 00 and No. 1 sand obtained from a supply house in Chicago, and on an Evansville sand submitted by a southern Indiana company. Tests were made according to the specifica- tions of the American Foundrymen's Asso- ciation.^ Tyler Standard sieves corresponding in size of openings to the U. S. Standard sieves were used for the screen tests. A Simpson muller-type laboratory mixer w^as used in tempering the sands. The compres- sion and permeability tests were made with a Dietert universal sand strength machine and a Dietert permeability meter. Acknowledgments This investigation was made under the supervision of J. E. Lamar, Geologist and ^Testing and grading Foundry Sands and Clays, Standards and Tentative Standards, Am. Foundrymen's Assn., 4th Ed., 1938. Head of the Industrial Minerals Division of the Survey. Cove Heilbronner, research assistant, aided in the field and laboratory studies. M. M. Leighton, Chief of the Survey, and G. E. Ekblaw aided in selecting promising areas for investigation, R. E. Grim checked the petrographic identification of the clay minerals, W. F. Bradley made X-ray deter- minations of the clay minerals, and O. W. Rees supervised the chemical analyses of sands. C. E. Schubert, of the Mechanical Engi- neering Department of the University of Illi- nois, permitted the use of a Dietert perme- ability meter. CHARACTER OF FINE-GRAINED MOLDING SANDS The fine-grained molding sands consid- ered in this investigation usually contain more than 75 per cent of grains smaller than 100 mesh and have grain fineness numbers higher than 150. It was hoped especially to dupli- cate two types of fine-grained sand : ( 1 ) that produced in the Albany, New York, district, and (2) that produced in southern Indiana. In order to provide a means of readily com- paring the sands, the Albany and southern Indiana sands are briefly described. Albany Sand An area extending for 100 miles along Hudson River valley and centering about Albany, New York, has been one of the principal sources of molding sand in the United States for many years, and sand from this district has been shipped as far as the west coast. The Albany sands have been de- scribed in detail by Nevin" and the following summary is based on his work except where noted otherwise. Origin. — During late Glacial time there was a large lake in the area now occupied by Hudson Valley. At a time when the margin of a glacier was near the lake, streams flowing from the melting ice carried large quantities of sand into the lake, and the sand was de- posited where the currents of the streams were checked. The sand consisted largely of quartz grains but contained many grains of shale and metamorphic rocks picked up by the glacier from the bedrock in the vicinity of the deposits as well as from areas to the ^Nevin, C. M., Albany molding sands of the Hudson Valley: New York State Mus. Bull. 263, 1925. FINE-GRAINED MOLDING SAND Table 1. — Variation in Grain Size of Albany Sand by Grades^ Grade Number Per cent on sieve 00 1 1^ 2 3 Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. 6 Tr 0.1 Tr 0.4 0.8 2 5 19 33 13 0.4 0.2 0.3 2 3 6 13 32 48 27 Tr Tr 0.6 1 2 4 16 17 8 0.3 0.4 0.2 0.5 4 5 18 22 29 47 22 0.1 0.1 0.5 7 11 11 16 14 4 0.2 0.2 1 10 17 29 25 22 24 24 Tr 0.5 11 8 5 6 6 6 5 0.1 0.8 0.6 2 27 26 18 14 18 29 17 0.1 0.1 0.8 23 8 4 3 3 6 7 0.3 1 3 10 57 21 13 9 12 22 15 0.2 0.7 1 2 32 3 2 1 2 5 9 8 12 3 20 3 40 .... 23 70 . . 64 100 7 140 3 200 3 270 6 Pan Clay 12 16 Grain fine- ness number 215 240 175 245 150 185 105 175 75 140 60 95 Number of samples 6 13 8 8 13 7 'After Nevin, C. M., Albany molding sands of the Hudson Valley: New York State Mus. Bull. 263, pp. 30, 36-49, 1925. north. Later the lake drained away and the present channel of Hudson River was cut down through the lake deposits. Consequent- ly the sands now occur high above the river in extensive flat areas, called terraces, which are remnants of the old lake bottom. After the lake disappeared, the sands were exposed to weathering processes which have continued to the present time and have developed a soil covering on the deposits. Rain water per- colating downward through the sands broke down the fragments of shale into small par- ticles of clay, decomposed the metamorphic rocks into clay and sand, and distributed the clay through the sand. The zone in which the clay occurs is the molding sand. Below it the sand is "sharp" and contains little bond. Thick?iess. — The average thickness of the molding sand deposits is 15 to 20 inches but the thickness ranges from a few inches to a maximum of about 8 feet. The over- burden consists of 10 to 12 inches of soil. Grades. — The Albany molding sand is marketed under six principal grades based on the coarseness of the sand and ranging from No. 00, the finest grained size,, through No. 0, No. 1, No. 11/^, No. 2, No. 3 to No. 4, the coarsest. The extreme grades, Nos. 00 and 4, are less common than the others. The separation of the different grades is difficult as all grades from No. to No. 3 may be found in an area no larger than an acre. Abrupt changes in grade are common and follow no set rule. The grade terms are not uniformly used by different producers although the variations are usually not more than a single grade. After a study of many samples, Nevin devised a method of grading on the basis of grain size which eliminated a considerable overlapping of the grades and indicated the average usage of the grade terms. The extent to which the grade terms overlap in actual practice was shown by the fact that in making this classification it was necessary to change the grade number of 20 out of 54 samples which had been submitted by a number of producers as their standard grades. The range in amounts of grains re- tained on each sieve for each grade is given in table 1, and the average grain size for each grade is given in table 2. Most of the Albany sand shipped into Illi- nois falls into grades 00, 0, and 1. These are briefly described below : ALBANY SAND Table 2. — Average Sieve Analyses of Albany Sand by Grades^ Per cent Grade Number on sieve 00 1 I'A 2 3 6 12 20 40 70 100 140 200 270 Pan Clay.... 0.2 0.1 0.2 1 2 5 8 23 40 21 Tr 0.1 0.1 0.3 2 3 9 13 24 34 15 Tr Tr 0.4 4 11 20 16 18 18 12 Tr 0.3 0.2 1 19 18 13 9 12 14 13 0.1 0.4 1 5 37 15 9 5 7 10 11 0.5 2 2 13 50 5 2 2 3 8 13 Number of samples 6 13 8 8 13 7 lAfter Nevin, C. M., op. cit. pp. 30, 36-49. No. 00 grade. — The No. 00 grade is the finest grained grade of Albany sand. Its grain fineness number ranges from 215 to 240, ac- cording to analyses of six samples studied by Nevin. The clay content ranges from 13 to 27 per cent and averages 21 per cent. These sands have a large proportion of pan material and 270-mesh sand, usually totaling 60 to 70 per cent (table 1). They contain less than 10 per cent of sand coarser than 140 mesh. The permeability ranges from 7 to 13, aver- aging 9, and the maximum cohesiveness ranges from 176 to 203 at 6.0 to 8.7 per cent water. The sample of Albany No. 00 grade sand tested in this investigation has a grain fineness number of 225 but does not exactly meet the requirements of the classification. It is about 6 per cent too low in 270-mesh grains, 5 per cent too high in 200-mesh grains, and has slightly more than 10 per cent of grains coarser than 140 mesh. In grain size it is more like the No. grade as defined by Nevin. This sample has, at 5.9 per cent water, a green compressive strength of 9.3 pounds per square inch and a permeability of 11.1. Other tests of Albany No. 00 sands are given in table 3. No. grade. — The No. grade of Albany sand as defined by Nevin includes a long range of grain size and almost completely overlaps the No. 00 grade sand (table 1). The 13 samples he studied have grain fineness numbers from 175 to 245. The average sand in this grade contains a little less pan material and more 200-mesh sand than the average No. 00 sand. Sands at the coarse end of this grade contain much less pan material than the No. 00 sand and also have roughly equal dis- tribution of the sand on the 140-, 200- and 270-mesh sieves. They contain less than 10 per cent coarser than 100-mesh. The perme- ability of No. grade samples tested by Nevin ranges from 8 to 22 and averages 13, and the maximum cohesiveness ranges from 133 to 251 at 6 to 11.9 per cent water. Two samples of Albany sand studies by Freeman'* had been designated as No. and No. 1 although they were similar in grain size as shown by the grain fineness numbers of 214 and 217. Both were No. sands in Nevin's classification. One had a permeability of 10.2 and a green compressive strength of 5.7 pounds per square inch at 6.1 per cent water and the other a permeability of 15.3 and a green compressive strength of 3.2 at 6.0 per cent water. Tests of typical Albany No. grade sands are given in table 3. No. 1 grade. — The No. 1 grade of Al- bany sand includes sands with grain fine- ness numbers of 150 to 185, as shown by 8 samples studied by Nevin. They generally contain a little less clav than the finer sands ^Freeman, C. H., Natural bonded molding sands of Canada: Canada Dept. of Mines, Mines Branch, No. 767, p. 131, 1936. 10 FINE-GRAINED MOLDING SAND Table 3. — Tests of Ai Sample number 209 254. AOO, 207 244, 369. 260 Al Grade 00 00 00 Source^ Sieve Analysis, Per Cent 0.30 12 0.14 0.26 20 0.06 0.12 30 Tr 0.38 0.02 0.08 0.20 0.18 0.02 0.10 0.16 0.10 40 0.26 0.32 0.09 0.6 Tr 0.30 0.02 0.15 0.36 0.40 0.4 50 0.2 70 1.16 0.86 0.66 1.0 0.4 2.12 2.48 2.29 2.36 100 1.28 2.44 140 2.26 5.88 2.0 3.6 6 4.92 4.02 4.26 11.08 10.24 15.6 50 13.30 6.75 20.34 27.12 21.4 'Source: A— Nevin C. M. op. cit., pp. 70-77. This report contains many other tests of Albany sand. The tests quoted are ot sands which had the same grade in Nevin's classification and in the trade designation of the producer. B— Samples from a supply house in Chicago; grades are trade designation; exact source unknown; tested in present mvestigation. C — Freeman, C. H., op. cit. p. 131. ALBANY SAND 11 New York, S.'^xds Retained ox Sieve Grain Compres- sive strength (lbs. sq in.) Water Permea- Bond 200 270 Pan Clay Total fineness number (per cent) bility strength 4.94 21.84 47.68 21.12 100.74 239 4.0 6.0 8.0 9.6 11.5 3.15 5.43 5.8 10.7 7.5 182 203 200 12.68 31.52 33.00 13.08 100.16 216 4.0 6.0 8.0 9.7 11.7 13.6 3.5 6.5 8.8 10.0 13.0 8.2 171 186 181 18.2 12.8 45.6 12.6 100.2 225 5.0 5.9 7.7 9.6 10.7 11.5 9.7 9.3 6.6 12.42 23.64 34.08 12.76 99.60 207 3.9 6.1 8.6 9.6 7.5 10.1 11.7 10.7 142 181 172 18.60 19.54 22.68 19.34 100.02 186 4.4 6.0 8.3 12.1 7.9 10.0 13.4 10.0 too drv 175 163 13.99 22.96 38.02 10.9 100.3 217 4.2 6.1 10.2 7.9 10.2 11.4 6.8 5.7 5.1 14.64 19.04 22.04 9.70 99.92 175 4.3 6.0 8.0 10.0 14.7 20.0 15.7 Too dry 178 161 19.46 16.16 14.10 10.24 99.72 153 4.3 6.0 8.3 9.9 14.7 21.0 22.7 20.0 140 173 149 22.2 11.2 17.0 9.0 100.4 152 3.8 5.5 7.4 19.8 26.0 27.9 9.4 6.3 4.4 Footnote to Table 4, pp. 12-13. Source : A — Littlefield, M. S., Natural bonded molding sand resources of Illinois: Illinois State Geol. Survey Bull. 50, p. 172, 1925. B — Logan, W. N., The foundry sands of Indiana: Dept. of Conservation, State of Indiana, Div. of Geol., Pub. No. 92, p. 10, 1930. C — Sample from an Evansville, Ind., company, tested in present investigation. D — Crane, P. W., Molding sand work at the University of Cincinnati: American Foundrymen's Assn. Trans, vol. 33, 829- 842, 1926. E — Freeman, C. H., Natural bonded moulding sands of Canada: Canada Dept. Mines, Mines Branch, No. 767, p. 132, 1936. 12 FINE-GRAINED MOLDING SAND Table 4. — Tests of Southern Sample number 25. 30. 2A 5A. 24 Troy, Ind 81 FS. 34, 1-J 47, 53 Localit Bauman, Ind Bauman, Ind , Rockport, Ind, Rockport, Ind Newport, Ky 91 Conneaut, Ohio. Delhi, Ohio. Canal Fulton, Ohio. Galliopolis, Ohio. Source 1 Jeffersonville, Ind. ... B Evansville, Ind. Sieve Analysis, Per Cent Windsor Locks, Conn. Fran( 12 02 20 06 .30 02 30 08 40 04 .06 50 .38 .44 .04 Tr .04 .04 .08 .08 .04 .54 .06 70 06 100 3.0 04 .2 7.4 140 0.2 1.3 .2 11.0 2 .2 .12 .li .4 07 94 20 1.2 .16 .22 .20 1.32 .42 2.0 2.2 2.6 .62 .32 1.62 1.77 .57 2.6 2.8 4.4 1.60 2.0 .66 2.76 5.62 'Footnote on p. 11. SOUTHERN INDIANA SAND 13 Indiana and Similar Sands Retained on Sieve Grain Water Permea- Bond Compres- fineness sive strength 200 270 Pan Clay Total number (per cent) bility strength (lbs. sq.in.) .04 .04 72.8 24.8 97.8 300 6 8 10 2.0 2.2 2.8 240.9 263.7 247.6 5.5 4.9 70.2 15.2 98.28 274 4 6 8 2.8 3.7 4.2 165.3 202.2 207.6 5.0 3.0 72.0 19.6 100.0 277 4.3 7.0 8.6 10.4 1.33 1.67 2.08 1.60 193 197 270 244 4.2 3.7 65.1 5.6 100.0 240 4.0 5.7 6.6 7.7 10.2 3.58 4.16 4.85 5.22 4.18 135 152 159 173 176 .3 .4 72.4 26.2 100.0 297 5.9 7.2 7.7 9.1 2.6 5.7 2.8 2.4 277 307 290 274 1.97 4.96 84.30 7.84 100.0 289 4.4 5.9 7.1 8.0 5.06 5.76 5.65 5.50 134 143 156 159 4.6 4.8 69.0 16.6 100.0 272 4.2 5.6 7.4 3.7 4.9 5.7 12.3 11.4 9.4 7.0 5.9 59.0 21.3 98.7 262 4 6 8 3.3 4.0 4.5 188.4 204.0 233.8 11.1 6.4 60.8 13.0 99.54 251 6 8 7.7 7.3 254.2 228.1 2.70 2.68 63.16 29.24 100.00 283 5.5 7.2 8.5 11.8 12.9 2.5 3.2 4.0 5.2 4.7 242 245 224 222 5.0 4.56 76.4 11.12 100.00 279 5.8 6.8 8.2 9.2 10.6 4.6 4.7 4.9 4.5 150 155 158 171 1.20 1.16 81.98 14.44 100.00 293 4.7 5.8 7.65 9.4 11.9 2.4 2.7 2.8 2.7 2.6 141 153 160 173 167 4.24 7.58 64.38 15.4 99.9 260 4.1 6.0 8.1 2.0 2.5 2.7 6.4 6.8 7.0 8.80 13.88 61.98 7.3 100.2 252 4.1 6.0 8.1 8.6 9.4 8.8 3.5 3.8 4.0 14 FINE-GRAINED MOLDING SAND and much less pan material. The sand is fairly evenly distributed between the pan, 270-, 200-, and 140-mesh sieves and usually also the 100-mesh sieve. The total amount coarser than 70 mesh is usually less than 10 per cent. The permeability ranges from 10 to 24, averaging 19, and the maximum co- hesiveness ranges from 139 to 206 at from 5.8 to 13.1 per cent water. The sample of Albany No. 1 sand submitted to us has a grain fineness number of 152 and differs from the grade as defined by Nevin only in being 5 per cent lower in grains retained on the 270-mesh sieve. It has a permeability of 27.3, and a green compressive strength of 6.3 pounds per square inch at 5.5 per cent water. Tests of Albany No. 1 grade sands are given in table 3. Southern Indiana Sand A molding sand finer in grain size than the Albany sand is produced in southern Indiana. This sand consists principally of grains passing a 270-mesh sieve (pan ma- terial) and has a grain fineness number be- tween 250 and 300. No general name has been applied to molding sands of this grain size although producing companies have their own trade names. For convenience, therefore, these sands are referred to in this report as the Southern Indiana sands, al- though other grades of sand are also pro- duced in that area. Sands of this grain size are also produced in northern Kentucky and central and northern Ohio, and some of them also enter the Chicago market. The following descriptions apply to the southern Indiana deposits unless otherwise noted. Distribution. — The Southern Indiana sands are produced chiefly in the vicinity of Sandale, west of Rockport, in Spencer County. Similar sands occur in several of the Ohio River counties, especially near Tell City, Evansville, Camelton, and Jefferson- ville. The deposits are principally in ridges and hills on terraces. Origm. — The Southern Indiana sands probably are wind-blown in origin, that is, they were carried by the wind, like dust, to their present location. Such deposits are called "loess." Some of these sands may be water deposits — materials carried by streams and laid down in the quiet w^ater of lakes. Weathering has leached the carbonates from the upper part of the deposits. Thickness and overburden. — The depos- its usually range from 3 to 10 feet in thick- ness and have an overburden of 1 to 3 feet of soil and clayey silt. They overlie cal- careous silt or sand. Grain size. — Sands of several grain sizes are found in southern Indiana but much of the sand, and especially that considered here, is largely pan material. Materials of this grain size are more correctly called "silts." However, they are called "sands" in the sand industry and in foundries, and this custom is followed here. The term "silt" is also used in the descriptions of the outcrops where needed to distinguish such materials from the true sands. Published data on 15 samples from south- ern Indiana, Kentucky, and Ohio, show^ that these sands rarely contain as much as 25 per cent of grains coarser than 270-mesh and often less than 5 per cent. They usually contain 60 to 85 per cent pan material and 5 to 30 per cent A.F.A. clay. The remainder is fine sand, nearly all less than 100 mesh in size. Tests of several Southern Indiana and similar sands are given in table 4. The clay content of some of the southern Indiana deposits is as high as 35 per cent in the upper part but only about 10 per cent near the base. Consequently it is possible to produce material with almost any clay con- tent desired between these limits. Fine- and medium-grained sand low in bond occur in the same area and the very fine grained ma- terials are blended with them in various pro- portions to supply sand to meet different specifications. Strength and permeability. — Tests on the 15 samples show these sands to have a maxi- mum bond strength ranging from 145 to 310, and averaging 220. The permeability ranges from 2.8 to 9, averaging 5.1. NORTHERN ILLINOIS SANDS 15 CHARACTER OF NORTHERN ILLINOIS SANDS Distribution Deposits of fine-grained molding sands which are similar in grain size to the Albany and Southern Indiana sands were found in Henry, Jo Daviess, Mason, Rock Island, and Whiteside counties. Large areas near Chicago which are underlain by sand were examined but no deposits which meet the grain-size requirements were found. One deposit near Chicago is a possible source of fine-grained molding sand although it does not have the same grain-size distribution as the Albany sands. The most numerous deposits of the Al- bany type sand were found in Whiteside County, especially in the area south of Mor- rison. Several promising samples were col- lected from deposits in Jo Daviess County near Aiken and in Mason County near Mason City. The only promising deposits of the South- ern Indiana type sand were found in the up- land areas near the Mississippi River bluffs. Deposits of this sand are present in Rock Island, Whiteside, Carroll, and Jo Daviess counties, but only the area in Whiteside and northern Rock Island counties was sampled in enough detail to show the general charac- ter and variations of the deposits. Origin Many of the deposits of fine-grained sand in southern Whiteside County are in a large area which was covered by a lake-like expan- sion of the Mississippi and Rock rivers dur- ing Glacial times. Most of the sand deposit- ed in this body of water was medium grained but at certain places where the currents were weaker fine-grained sand was deposited. Conditions were probably similar farther north along Mississippi Valley when the deposits were laid down near Aiken and Rice in Jo Daviess County. The sand form- erly covered a much larger area than at present, but much of it has been eroded by the streams and rivers. The remaining de- posits occur in terraces and dunes at various levels above the bottomlands of the rivers. In the area south of Morrison and in northern Rock Island County, sand forms many steep-sided, ridge-like hills, usually elongated in an east-west direction. Much of this sand is also medium grained although in some areas, as at Round Grove and north- west of Lyndon, some of it is fine grained. The origin of these hills is uncertain but the sand was probably deposited in a large body of water although locally it has been modi- fied by wind action. Near Mason City the most promising de- posits are low dunes in the upland area east of Illinois Valley. The sand probably has been carried by the wind from sand deposits in the terraces along Illinois Valley. The most promising deposits of the South- ern Indiana type of sands are all in the loess deposits near Mississippi Valley. The de- posits were formed during the Glacial period. At that time the Mississippi River was laden with sediments from the melting glaciers and when the w^ater was high fine-grained ma- terials were deposited widely over the bot- tomlands. When the water was low the deposits dried out and the fine-grained dust- like materials were easily picked up by the winds and carried onto the uplands. Sand deposited by glacial waters, or picked up by the wind from glacial deposits and re- deposited, usually contains a large amount of carbonates derived from the fine grinding of blocks of limestone and dolomite during the movement of the glacial ice. Such sand as originally deposited is of little value for most foundry uses because the carbonates reduce its refractoriness and give it other undesirable properties. The glacial sands of Illinois, however, have had the carbonates leached from the upper part of the deposits by rain water percolating downward through the sand. The solutions have also carried clay from the surface soil zone and have deposited it in the upper part of the zone from which the carbonates have been leached. Usually the amount of clay ranges from its greatest concentration near the top of the noncalcareous zone to its lowest amount at the base of the zone. The lower part of the noncalcareous zone usually contains little if any more clay than the calcareous, un- weathered material below. The transition zone from the noncalcareous to the strongly calcareous material below is thin in deposits like loess, usually about 1 inch, but in the coarser grained deposits it may grade through a zone of a foot or more. The zone from which the carbonates have been leached and in which a clay bond has been deposited is of workable thickness at 16 FINE-GRAINED MOLDING SAND many places. As this zone always occurs immediately below the surface, only the top soil has to be removed as overburden before excavating the molding sand. Mineral Composition The grains in the Illinois sands are most- ly quartz with smaller amounts of several other minerals, particularly feldspar. Many grains have a thin coating of limonite which gives them a light yellow color. The quartz grains are angular and subangular in shape. The Illinois sands are not distinguishable from the Albany sands in shapes of grains. The sands differ in some of the minor min- erals but these minerals are not abundant enough to affect the uses of the sand. The material separated as the clay grade in the standard method of analysis of the American Foundrymen's Association in- cludes all the grains of diameter smaller than about 20 microns. This material is a mixture of quartz, clay minerals, limonite, and organic substances. Quartz and clay minerals vary considerably in relative abun- dance. The clay minerals occur almost en- tirely in grains less than 2 microns in diame- ter. In some sands, however, the clay particles are abundant in aggregates between 2 and 20 microns in diameter. Some quartz is present in the minus 2-micron material and the grains between 2 and 20 microns are predominately quartz. The bonding substances in the sands con- sist of clay minerals, limonite, and organic substances. Organic substances are minor and limonite is not abundant. The per- centages of iron oxide in three Illinois sands, in an Albany sand, and in a Southern Indi- ana sand are similar (table 5). Table 5. — Amount of Ferric Oxide in Molding Sands^ Sample Fe203 number (per cent) Albany No. 00 2.26 Evansville 3 . 23 25 1.65 36 2.72 39 2.64 ^Analyses by Geochemical Section, Illinois State Geological Survey under the supervision of Dr. O. W. Rees. Because the clay minerals are the most important bonding substances in the sand, an attempt was made to determine what clay minerals were present in order to com- pare the Illinois sands with the Albany and Southern Indiana sands. Some of the ma- terial less than 2 microns in diameter was separated from 16 Illinois sands, two Albany sands, and one Southern Indiana sand. Limonite was removed by solution in dilute hydrochloric acid. The indices of refraction of aggregates of the grains were determined by immersion in liquids of known indices of refraction. Most of the clays from the Illi- nois sands had similar indices with their lowest index about 1.525 and their highest index about 1.545. A few had indices as high as 1.550 and one had an index as low as 1.515. The clays from the Albany and Southern Indiana sands had indices from 1.545 to 1.565. Thus the highest index of the Illinois clays was about equal to the lowest of the Albany and Southern Indiana clays. X-ray identifications of the clay minerals were made on clays separated from a typical Illinois sand (sample 25), a Southern Indi- ana sand, and an Albany sand. All three were largely illite. The Albany clay also contained a small amount of montmorillo- nite, a little kaolinite, and some quartz. The Southern Indiana clay, in addition to illite, contained kaolinite and quartz, although less than the Albany clay. The Illinois clay con- tained about as much kaolinite and quartz as the Southern Indiana clay and a little montmorillonite although less than the Al- bany clay. In mineral content, the clays differ chiefly in the relative abundance of the minor constituents although no mont- morillonite was found in the Southern Indi- ana clay. The difference between the indices of re- fraction of the clays from the Illinois sands and the clays from the other sands apparent- ly is not due to the influence of the minor constituents of the clay minerals or to vari- ation in the amounts of quartz. Although the interpretation is somewhat uncertain, the most probable explanation is that the sands contain different forms of illite. The Al- bany clay contains illite with relatively high indices of refraction, although the presence of montmorillonite, kaolinite, and quartz, which have relatively low indices, gives the aggregates average indices below those of purified illite. According to this explana- tion the illite in the Illinois clays has much lower indices than the illite in the Albany NORTHERX ILLINOIS SAXDS 17 clay, as the indices of the aggregates are below those of its other constituents, kaoli- nite and quartz. Although the Illinois clays contained a little montmorillonite, the amount was too small to influence appre- ciably the indices of refraction. Grain size The samples of Illinois sand represent al- most all degrees of coarseness through the range investigated. The grain fineness num- bers of 42 samples are between 150 and 250, the interval of the Albany sands of grades 00, 0, and 1, and those of 37 samples are between 250 and 300, the interval of the Southern Indiana sands (table 6). Many of these samples do not meet other requirements of the Albany and Southern Indiana sands. A common defect is the presence of too much A.F.A. clay. Also the gradation of grain size may differ radically in two sands even though they have the same grain fineness number. Consequently it is important, in attempting to duplicate the Albany and Southern Indiana sands, that a sand have about the same gradation in grain size, that is, about the same amounts of each sieve size. It is uncertain how closely a sand should coincide with the Albany limits for each sieve size in Nevin's classification (see p. 8). The common variations in the grain size of the sand in the Albany deposits, and con- sequently the variation in the sand shipped from time to time, indicates that quite a range in percentages on one or more sieves is possible. Furthermore, many published analyses of Albany sand do not coincide exactly with the size limits of Nevin's classification. There seems to be no evi- dence that the gradation of the Albany sand is the only suitable gradation, or even the best gradation for any particular use. For these reasons, sands that differ slightly in the amount of grains retained on one or two sieves are still considered as of possible use. Even sand that is quite short on one sieve size is still considered to have possibilities if amounts of adjacent sieve sizes counter- balance the deficiency . Excessive amounts on the coarsest or finest grained sizes are more important because an excess of fine particles will reduce the permeability whereas an excess of coarse grains will affect the finish of the castings. Most of the Illinois sands do not exactly coincide with the grain size of the Albany sand as defined in Nevin's classification al- though some of them are very close. The Illinois sands commonly have a lower con- tent of grains retained on the 270-mesh sieve than the Albany sands. Some of the Illinois sands appear to have a grain size almost identical with the South- ern Indiana sands. However, since 60 to 75 per cent of the sand consists of pan ma- terial that is not further subdivided in the standard sieve analysis, there may be size variations within the pan material that might affect the properties of the sand. Permeability The Illinois sands have permeabilities ap- proximately the same as the corresponding grades of the Albany and Southern Indiana sands (table 9). Strength Many of the sands tested have a green compressive strength higher than that of the Albany and Southern Indiana sands, although the grain size and A.F.A. clay con- tent are about the same. Exact comparisons between A.F.A. clay content and strength are not to be expected because the amount of A.F.A. clay is not necessarily proportion- al to the amount of clay mineral which gives the sand its strength. It is probable, how- ever, that the differences in the strength of the sands are probably due to the differ- ence in the character of the illite, the chief clay constituent. The structure of the min- eral illite is such that with changes in its composition which would lower its indices of refraction, it approaches the structure of the mineral montmorillonite." Its proper- ties might therefore be expected to approach those of montmorillonite. Montmorillonite is the chief constituent of bentonite clays which are used extensively as bond clays and which have greater bonding power than kao- linite or illite clays. It would be expected, therefore, that the clays in the Illinois sands might have a somewhat higher bonding power than the clays in the Albany and Southern Indiana sands. Consequently Illi- nois sands can probably be used with a slight- ly lower A.F.A. clay content than would be acceptable in the Albany or Southern Indi- ana sands. For sands of the same green com- ^Grim, R. E., personal communication. IB FINE-GRAINED MOLDING SAND Table 6.— Samples of Northern Illinois Sands Listed by Fineness Numbers^ Grain fineness number A.F.A. clay (per cent) Sample number Grain Class No. 5 4.6 1.0 70 110 Grain Class No. 4 8 4 5 6 6 4 12.0 24.4 29.6 28.4 10.8 13.0 103 54 100 102 109 104 95C 94 B 64 95B 107 94A 8 55C 50 92C 106 6A 9 63 B Grain Class No. 3 6.8 16.0 4.8 7.0 9.8 5.0 29.8 8.0 6.6 2.6 8.2 12.2 5.8 21.4 14.0 19.8 47 11 58A 60 61 63 99 10 63A 58B 59 95A 6 3D 12 56 98 14 18 55A 45 5 Grain fineness number A.F.A. clay (per cent) Sample number Grain Class No. 3 — (con't) 120, 120. 120. 130, 131, 132, 133, 135, 137, 138. 200 200. 205. 211. 25.2 26.9 30.4 3.4 28.4 9.4 22.2 14.0 39.0 10.8 3AB 55B 57 68B 91 69 B 97A 105 3C 78A Grain Class No. 2 140 32.6 4 140 8.6 72 141 25.0 97B 148 15.6 28A 152 37.2 92A 155 2.4 25B 155 24.0 52 155 11.6 84A 157 34.0 7 157 7.4 28C 159 7.6 73C 159 5.4 84B 161 18.8 29 163 23.8 96A 166 16.2 73A 169 14.6 51 170 19.0 39A 173 8.2 39B 177 29.2 41 179 15.0 28B 182 14.8 78B 182 31.8 93A 183 36.6 1 187 15.0 65A 189 12.0 96B 190 71.4 62 192 6.0 25 192 17.8 65AB 197 28.2 2 198 50.2 92B Grain Class No. 1 2.6 34.8 30.2 12.0 32 90 27 25A Grain fineness number A.F.A. clay (per cent) Sample number Grain Class No. 1 — (con't) 215 38.0 49 215.. 19.0 65B 219 21.0 67A 222 22.2 38 222 36.2 48 223 37.8 22 224 24.4 82 226 18.4 30 228 23.4 75 229 20.0 73B 230 38.4 93B 234 35.8 69A 255 59.4 101 256 18.8 81B 260 32.4 31 261 26.6 37 266 26.0 74 269 32.2 86A 271 15.8 87 273 23.4 88B 275 37.2 68A 276 51.2 20 278 27.0 77B 278 30.4 81A 279 34.6 43 280 34.2 65C 281 21.8 34 282 39.6 :i3 282 38.2 67B 286 28.6 35 288 20.0 36A 289 23.2 36 289 28.4 86B 290 29.8 40 290 39.4 83 291 30.4 44 291 34.2 77A 291 26.6 80B 291 15.6 108 292 41.2 66 292 26.8 80A 293 44.4 26 293 12.2 36B 293 26.0 42 294 37.6 79 294 45.0 85 295 43.8 71 295 34.8 88 A 297 46.8 89 iThe grain fineness numbers are classified by the A.F.A. into grain classes as follows: Grain class Grain Fineness Nos. No. 1 200 to and including 300 No. 2 140 to but not including 200 No. 3 100 to but not including 140 No. 4 70 to but not including 100 No. 5 50 to but not including 70 BLENDING AND PROCESSING 19 pressive strength and grain size, the Illinois sands might have a slightly greater permea- bility. Durability Tests to determine the durability or life of molding sands have not been standard- ized and it was not possible to determine this important characteristic of the sands examined. Use of the sands under foundry conditions will probably be necessary to determine whether or not the Illinois sands are as durable as the Albany and Southern Indiana sands. The durability of molding sands depends largely on the ability of the bonding ma- terials to retain their bonding power after heating. The bond of the sands studied is chiefly clay with small amounts of limonite and organic matter. Organic matter is a nondurable bond since it is readily burned out of the sand. Most of the Illinois sands tested contain little organic bond. Limonite is present in all the samples in small amounts. When heated to over 180° C.*^ limonite loses its ability to rehydrate and thus loses its bonding power. Highly limonitic sands were avoided in sampling, and determina- tions of the amount of ferric oxide in several samples show that the limonite content of the Illinois sands is comparable to that of the Albany and Southern Indiana sands (table 5). The clay minerals also are permanently dehydrated and thus lose their bonding power when heated above a cer- tain temperature. This temperature is dif- ferent for the different clay minerals but is probably over 450° C. for all clay minerals. However, the clay minerals in the sands studied are so nearly alike that no great difference in durability is to be expected. A preliminary investigation indicated there is little difference in refractoriness between the Albany and Illinois sands of similar grain size. Uniformity A characteristic of the Albany sand which has favored its use is that its physical proper- ties change very little with small variations in water content so that careful control of temper is not essential. The tests show that sPosnjak, E., and Merwin, H. E., The hydrated ferric oxides: Am. Jour. Sci. 4th Series, vol. 47, pp. 311-348, 1919. some of the Illinois sands are probably equal to the Albany sand in this respect while others are not. In recent years many foun- dries have adopted testing methods which permit close control of the properties of the sands, and this may make it possible to use sands formerly thought to be unsatisfactory. Where sand control methods are used, it is said : "The use of cheaper local sands is a possibility for considerable savings. The use of such sands might be risky if their con- dition were not known at all times, but when properly handled, they are superior to a more expensive sand without control."" BLENDING AND PROCESSING Although some of the Illinois sands de- scribed are probably suitable in their natural condition for the uses of the Albany and Southern Indiana sands, many of them could be improved by blending with other sands or by processing. A common fault of some Illinois sand is excessive strength. This could be corrected by blending such sand with a low-clay sand. Some sands which are weakly bonded could be improved and their uses extended by the addition of clay. For specialized uses requiring an accurately con- trolled sand which would command a pre- mium price, some processing such as washing, screening, crushing, or perhaps air classifi- cation might be feasible. Blending of sands has several advantages. Specifications for sand with certain physical properties can be met by controlling the grain size and amount of clay. The product can also be held more uniform than the natural run of many pits. With a blending plant an operator could supply sand suitable for many more uses than could otherwise be met from one or two deposits. The most abundant fine-grained sands were found in Whiteside County, and as coarser grained sands are also available a blending plant might well be located in that area. A considerable quantity of foun- dry sand is used in the Moline-Rock Island area not far away. To supply the Chicago district a plant located near Chicago w^ould have certain advantages because that area contains much sand which might be used in some blends and would thus cut down the amount of sand to be transported. ''Eggleston, G. K., Fundamental considerations in non- ferrous sand control: Am. Foundrymen's Assn. Trans., vol. 8, no. 4, p. 121, 1937. 20 FINE-GRAINED MOLDING SAND The possibility of improving some of the sands by blending is discussed under the description of the deposits. The sand from Lansing, south of Chicago, is unlike the Al- bany sand in certain respects, but because of its favorable location, attempts were made to alter it by blending with other sands (p. 33 ) . Similar combinations are possible with many other sands, but as emphasis was placed primarily on finding natural deposits like the sands now used, methods of improving the other sands were not studied. Many of the sands which did not have a grain size similar to that of the Albany and Southern Indiana sands (table 13) might be used in producing blended sands. Some molding sands which contain an excess of larger grains might be improved by crushing. A sand with a grain fineness num- ber of 58 was run through a laboratory roll crusher set to crush the grains over 70-mesh and the sand was reduced to a grain fineness number of 136. A considerable variation in grain size is possible by controlling the spac- ing of the rolls and the rate of feed. It is also possible to produce synthetic sands sim- ilar in grain size to the Albany No. 1 and finer sized grades by crushing medium- grained sands and adding bond clay. It is probable, however, that some screening would be necessary since an excess of pan material may be produced in crushing. The Ottawa silica sand and dunes in the Chi- cago area and elsewhere in northern Illinois are possible sources of medium-grained sand for this use. USES OF FINE-GRAINED MOLDING SANDS Fine-grained molding sands are used prin- cipally as molds in the manufacture of brass, bronze, aluminum, and light-weight gray- iron and malleable castings, and as facings for heavier castings. Many of the stronger fine-grained sands are used for addition to heaps where renewal of bond is needed. Nevin*^ summarizes the uses of Albany sands as follows: "Albany No. 00 — Low permeability and used only for the smallest castings where a smooth finish is essential. "Albany No. — Small brass, aluminum, and gray-iron castings, an admirable stove plate sand. "Albany No. 1 — For the average castings of from 5 to 75 pounds." Dietert and Woodliff*^ studied samples of sand from 13 nonferrous foundries and part of their data is summarized in table 8. Tests on samples which show the range of sand used for brass and aluminum castings are given in table 7. It has been stated^^ that a good molding sand for aluminum alloys will generally meet the following specifications: Compressive strength (lbs. per sq. in.). . 5-9 Permeability 4-8 Clay content (per cent) 20-35 Grain fineness number 175-250 Coarser sand with less clay can be used. sNevin, C. M.. op. cit., p. 69. 'Dietert, H. W., and Woodliflf, _E., Study of nonferrous molding sands: Am. Foundrymen's Assn. Trans., vol. 8, pp. 83-96, 1937. loRecommended practice for sand cast aluminum al- loys, Rept. of Nonferrous Div., Committee on Recom- mended Practice, Am. Foundrymen's Assn. Trans., vol. 6, no. 6, p. 2, 1935. T -Tests of Sands Used for Sample number Metal Weight of castings Sieve Analysis, Per 12 20 30 40 50 70 4 2 5 11 9 14 15 Aluminum and bronze Aluminum Aluminum and brass Brass Brass Brass Bronze 14-10 lbs.... 5-100 lbs.... 5-200 lbs.... 1 OZ.-300 lbs 10-75 lbs.... 45-200 lbs... 1-500 lbs.... 0.3 0.9 0.1 0.1 0.5 0.5 0.5 3.0 0.1 0.2 0.7 0.4 0.4 0.4 2.6 0.4 1.1 1.7 0.6 1.3 0.2 4.8 0.6 3.6 4.1 2.7 4.2 6.3 6.7 1.2 6.8 13.4 9.8 10.7 1.5 9.5 iDietert, H. W., and Woodliff, E., Study of non-ferrous molding sands: Am. Foundrymen's Assn. Trans, vol. 8, pp. 83-96, 1937. USES OF SANDS 21 I III I JO DAVIESS . STEPHENSON i WINNEBAGO | BOONE ' McHENRY ' LAKE I I Rockford I I 7-32.77.76^ _J /4./5I , | ~~r" \^o.A2L-L y Elgin «f '^^'^^ I Clicago DU PAGE I Aurora I •!-- Fig. 1. — Distribution of samples by counties. Aluminum, Brass antd Bronze Castings^ Green L ENT Retained on Sieve Grain fineness number Water (per cent) Green per- mea- bility com- 100 140 200 270 Pan Clay strength lb. sq. in. 1.1 3.8 5.5 9.1 53.2 24.9 254.0 6.4 3.0 8.8 3.6 5.2 7.0 8.8 42.5 21.1 212.5 8.3 3.0 8.7 8.9 11.8 13.5 11.7 22.9 10.2 154.5 8.0 13.0 5.2 8.6 11.6 11.2 11.7 29.9 13.0 175.7 6.3 12.0 7.9 8.6 14.3 14.0 11.1 22.3 12.3 155.8 6.0 14.5 7.7 31.2 9.5 9.0 9.6 17.6 12.9 137.5 7.2 19.0 6.2 5.8 7.3 8.4 10.0 26.7 14.3 155.2 7.2 9.0 7.7 22 FINE-GRAINED MOLDING SAND NORTHERN ILLINOIS DEPOSITS General Statement In these preliminary investigations only those deposits were studied where the to- pography indicated the possibility of large deposits. The descriptions of the individual deposits are based on exposures in road cuts, natural outcrops, and sieve analyses of one or two samples. Many sand deposits show a large range in grain size ; from most of them sand could be produced with a little finer or coarser grain size and with a larger or smaller amount of A.F.A. clay than is indicated by the few analyses avail- able. Because of the variability of the de- posits it is necessary to prove the presence of a large deposit of suitable sand by dig- ging test pits or drilling auger holes and testing the resulting samples. Before any extensive development is undertaken the sand should be tested thoroughly under foundry conditions. Promising samples of sand were collected from deposits in Cook, Henry, Jo Daviess, Mason, Rock Island, and Whiteside coun- Table 8. — Properties of Sands Used for Aluminum and Brass Castings^ Property Aluminum Brass Grain fineness ^'^^ number ^l^ 154.5 209.0 254.0 137.5 156.4 175.7 A. F. A. clay ^in. (P-"'^^) Max. 10.2 20.2 27.5 10.2 11.9 14.5 r^ Min. Green permea- « biiity .^;''- •^ Max. 3.0 5.5 13.0 12.0 16.3 28.0 Green compres- Min. sive strength Av. (lbs. sq. in.) Max. 5.2 7.5 8.9 3.9 6.4 7.9 Number of samples 6 9 iDatafrom Dietert. H. W., and Woodliff, E., Study of non-ferrous molding sands: Am. Foundrymen's Assn. Trans, vol. 8, pp. 83-96, 1937. ties. The tests of the most promising of the Albany type of sands are given in table 9 and of the Southern Indiana type of sands in table 11. Many other deposits were examined in Bureau, Carroll, Ford, Grundy, Iroquois, Kane, LaSalle, Lee, McHenry, Marshall, Ogle, Peoria, Tazewell, and Will counties but no favorable deposits were found. As a general rule the sands in these counties are coarser grained than the Albany No. 1 sand and the sandy silts contain too much clay to qualify as Southern Indiana type. Many of the deposits examined differed in some important respects from the Albany and Southern Indiana sands and were not sam- pled. Tests of most of the samples collected in the above counties are given in table 13. The distribution of the samples by coun- ties is shown in figure 1. ALBANY TYPE SAND The grain fineness numbers of 42 of the samples collected were between 150 and 250, the range of the Albany Nos. 00, 0, and 1 sands. Of these the samples from 15 deposits had a grain size distribution sim- ilar to the Albany sands, and these deposits are described individually, according to grade, and alphabetically by counties. Many of the other samples were less promising because of a high A.F.A. clay content or a radically different gradation of grain size from the Albany sands. They are discussed briefly by counties or by groups of counties that contain similar deposits. PROMISING DEPOSITS Albany Type No. 00 Grade Deposit near Rice, Jo Daviess County Sand similar to the Albany No. 00 grade occurs in a terrace deposit along the east side of Mississippi Valley near Rice, about six miles south of Galena in Jo Daviess County (fig. 2). The sand is exposed in a road cut at the base of a hill one mile south- east of Rice, in the NW. 1,4 NE. 14 NE. 14 sec. 22, T. 27 N., R. 1 E. ALBANY TYPE NO. 00 GRADE 23 O LOCATION OF SAMPLE r^\ AREA FAVORABLE FOR PROSPECTING ^-^ FOR FINE-GRAINED SAND R.I E SCALE '/2 Fig. 2. — Locations of samples collected near Rice and Aiken in Jo Daviess County. The exposure is as follows: Ft. in. Soil, dark brown 8 Silt, clayey, dark brown, noncal- careous (sample 31) 2 6 Sand, very fine-grained, silty, brownish-gray, noncalcareous (sample 30) 3 Sand, very fine-grained, silty, light brownish-gray, calcareous, base concealed 10 The 3 feet of very fine-grained sand represented by sample 30 is similar to the Albany No. 00 grade sand. The results of the tests of sample 30 are given in table 9. The sample differs in grain size from the No. 00 grade in that it contains less sand retained on the 270-mesh sieve and has a slightly higher content of 100- and 140- mesh sand. It might also be classed as a No. sand although the 46 per cent of pan material is more typical of the No. 00 grade. The sample tested contains 18.4 per cent A.F.A. clay, a little below the average of No. 00 grade sands. It has a maximum green permeability of 15.3 at 6.4 per cent water which is high. The permeability of 15.2 at 8.5 per cent water indicates a long range of suitable permeability. The sand has a high green compressive strength of 16.3 pounds per square inch at 6.4 per cent water in spite of the comparatively low clay content for this grade of sand. The clayey silt (sample 31) overlying the sand might be used as a Southern Indi- ana type sand although it is higher in clay. Its possibilities are discussed on page 45. This deposit is in a terrace which extends east and west along the south side of a small valley tributary to Mississippi Valley. It is about a quarter of a mile wide and one mile long, along the south side of section 15 (fig. 2). The top of the terrace is much 24 FINE-GRAINED MOLDING SAND CO ^ C ON to O --H lOf^ o O O t^ r^j ^ CN 00 NO 00 00 Thi to t^ t^ ro '— 1 NO t^ m dj (u '0 u "^ — , -H OO NO t^ fO fN t^ 00 Tt o Nor^ '^ LO OO CN NO Tf to ONt^ NO NO NO NO On lO lO fN lO O lO lo NO r^i ■^ O 00 t^ t^ CN O fT) '-I ro ON t^ '•— 1 ^— 1 ^— 1 '<— 1 1— 1 1— 1 '•—1 1—1 ■^ rg ro 1— 1 1— 1 1— 1 i-H lO NO NO NO CN CS CN «-, • — * T-H 1§ fO lO NOt~- "* NOOO Tt lOt^O^ erJioooo PO lO t^ 00 ^ CN -^ lO ro NO 00 ^1 CN NO (N o ON 'f ,_, C '^ ^ Q C^ On' O^ o c^ o o o ON ON ON o ON H ■^ ■^ as o '^ r^i o NO o TtH NO 00 r^i Ov' rl^ to ^ u Ol '"' 00 o NO 00 r* r^^ 00 c d NO O^ '^ NO fN fN 1—1 CO •^ NO o f^l NO OJ NO o o fO NO ^ t^ 00 ^ 1—1 o -rt^ 00 o o CN NO 2: 8 1^ ^ lO lO TlH ^H O^ ^ ■^ ^ '"' o NO r^i o o Tf oa Z § o r— 00 NO ID to TtH o 00 CN Tf ~o oo u Oh c/T 8 t^ 00 fN lO NO ro t-» CN ^ NO NO fN "^ 00 ■^ o >^ o r^j ^ d CN rr> ^ ^ ^ r^ < < 00 "* CN 00 ■^ rf w O ^ d V. o d O d lO H u un '^ CN S o H H o H ^ H u H H (U Id o o o o ^ 1— 1 /-L «-. O ^ o ii 1j CO OJ Q '55 OJ 15 15 u 3"^ ^ o ^ ^ S s ^ fe < NO a n IT) o 00 ON ,—1 ^ ro E S CN ro fO ro lO NO 2 rt 3 CD c ALBANY TYPE NO. 00 GRADE 25 OS »-" lO IT) Ot^ \0 t~- OS fS \0 to f<0 CN T^ O to Tt Os so ioo oso-^T) oioo t^ O lo lO -^ 0 r^OOs OsOOsO vOsOiO'-H OOsOO r^t^CN ^. o »H O '"' ^fH o '"' o vC 26 FINE-GRAINED MOLDING SAND dissected by gullies but the flat areas be- tween the gullies have an elevation of 720 to 760 feet, averaging about 140 feet above the Mississippi River bottoms. The road cut from which the samples were obtained is near the east end of the terrace, and the samples are probably typi- cal of the materials in that part of the ter- race. The noncalcareous sand is confined to the weathered zone, and the broader undu- lations of the surface of the terrace are not likely to affect the presence of suitable sand. The sand deposit is at least 12 feet thick, and any of this sand where weathered prob- ably would give a suitable material. How- ever, thorough prospecting by auger borings or test pits is necessary to determine whether sand similar to that sampled underlies all of the terrace or enough of it to be worked commercially. Similar deposits may also oc- cur along the slopes east and north at about the same elevation. The terrace is about half a mile south of the Chicago Great Western Railroad sid- ing at Rice. Deposit at Round Grove, Whiteside County Fine-grained sand occurs in a long ridge- like hill along the south side of the Chicago and Northwestern Railway at Round Grove, about four miles east of Morrison, in Whiteside County. The sand is exposed in a deep road cut at Round Grove, in shal- low road cuts along the north side of the hill east of Round Grove, and in an aban- doned molding sand pit west of Round Grove. On the east side of the deep road cut at Round Grove, in the SE. cor. NE. i/J NW. 14 sec. 25, T. 21 N., R. 5 E., the following exposure occurs: Ft. Soil, sandy, brown 6 Sand, fine-grained, slightly clayey, reddish-brown (sample 73A) .... 3 6 Sand, very fine-grained, clayey, brown, slightly darker than above, noncalcareous (sample 73B) 2 6 Sand and coarse silt interbedded, light brownish-gray, calcareous; in }/2- to 2-inch layers, which are mostly horizontal but include some cross-bedded layers; con- taining a few thin beds of coarse sand; base concealed (sample 73C) 8 In a road cut along the south side of the secondary road in the SW. 14 SW. 14 NW. 1/4 sec. 30, T. 21 N., R. 6 E., the following materials are exposed : Ft. in. Soil, silty, dark gray 1 Silt, sandv, reddish-brown (sample 74) 3 6 Sand and silt interbedded, like basal unit in outcrop described above, calcareous, base concealed 3 The section in the abandoned molding sand pit in the SE. 14 NE. i/J NW. i/4 sec. 25, T. 21 N., R. 5 E., is slumped, but according to Littlefield^^ 12 feet of cal- careous sand was worked. Of the samples described in the above sections, sample 73 B has a grain size closely similar to that of the Albany No. 00 grade sands. Sample 73A is nearest the Albany No. 1 grade and is further described on page 40. Sample 74 is a Southern Indiana type of sand, described on page 43. Sample 73C is similar to Albany No. 1 sand in grain size, but is highly calcareous and therefore not comparable to the Albany sands. Two samples collected by Littlefield (samples 65 and 66, table 12, p. 46), one representing the upper 8 feet and the other the lower 4 feet of sand exposed in the molding sand pit, were both similar in grain size to sample 73C and also were calcareous. Results of tests on sample 73B are given in table 9. The sand differs in grain size from the Albany No. 00 grade in contain- ing less sand on the 270-mesh sieve and a little more sand on the 100-mesh sieve. Its permeability is 11.8 at 5.6 per cent water, and 11.2 at 9.1 per cent water. This is a little higher than the average for the No. 00 grade sands and is a good range of uni- formity. Its green compressive strength is high, 14.6 at 5.6 per cent water and 10.3 at 9.1 per cent water. The sand is also similar in grain size to many of the finer grained Albany No. grade sands but because of its relatively high percentage of pan material, it is more typical of the No. 00 grade sands. Its permeability is high enough for it to be considered a No. grade sand although it is a little lower than the average for that grade. "Littlefield, op. cit., p. 144. ALBANY TYPE NO. GRADE 27 The outcrops are in a ridge about I14 miles long and about an eighth of a mile wide. The crest of the ridge is 30 to 40 feet above the adjacent areas. The greater part of the sand is calcareous and only the weathered zone, 4 to 6 feet thick, contains noncalcareous sands. The weathered zone is somewhat thicker along the crest of the hill than lower along the sides. In the road cut at Round Grove the Al- bany type No. 00 grade sand (sample 73B) is overlain by SV? feet of sand similar to the Albany No. 1 grade. As the lower sand is only about 2]/z feet thick it probably could not be worked unless the No. 1 grade sand were also used. The amount of No. 00 grade sand available is not evident from the outcrops, and it will be necessary to make auger borings or test pits along the sand ridge to determine the size of the de- posit. The greater part of the deposit ap- pears to be No. 1 grade sand. Road cuts near the east end of the ridge also expose at a lower elevation a calcareous fine- grained sand, probably No. 1 grade, over- lain by a very fine grained material, prob- ably loess, which is finer grained than the No. 00 sand and is similar to Southern Indiana sand. The best prospects for find- ing the No. 00 grade sand are along the higher parts of the ridge. Because the surface of the hill is irregular, the grain size of the material in the weathered zone may be found to vary sharply. This would necessitate careful grading and perhaps pro- duction of a large quantity of No. 1 grade sand in proportion to the amount of No. 00 grade sand. These characteristics empha- size the need for careful prospecting in this type of deposit. Other similar but lower hills south of the hill described may also contain deposits of molding sand. The Soil Survey map of Whiteside County^ ^ indicates that they are similar to the hill at Round Grove which is described as mixed sand and loess. These hills are in the SE. l4 sec. 25, NE. I/4 sec. 36, T. 21 N., R. 5 E., SW. ]4 sec. 30, and the NW. H sec. 31, T. 21 N., R. 6 E. The area is adjacent to the Chicago and Northwestern Railway and is about one mile northwest of the Chicago, Burlington and Quincy Railroad. i2Smith, R. S., Ellis, O. I., DeTurk, E. E., Bauer, F. C, and Smith, L. H., Whiteside County soils: Univ. of Illinois. Agr. Exper. Station, Soil Report No. 40, 1928. Deposit near Denrock, Whiteside County Fine-grained sand occurs in a large ter- race area near Denrock, about two miles west of Lyndon in Whiteside County. It is possible that No. 00 grade sand could be produced although most of the samples from this area are No. grade. The area is discussed in detail under the No. grade sands (p. 30). Albany Type No. Grade Deposit at Aiken, Jo Daviess County Sand similar in grain size to the Albany No. grade sand occurs in a terrace at Aiken, about four miles south of Galena in Jo Daviess County (fig. 2, p. 23). Mold- ing sand was formerly produced from a pit on the south side of the Chicago Great Western Railroad about an eighth of a mile west of Aiken. The sand is exposed in a road cut at the edge of the terrace near Smallpox Creek in the SE. i^ SW. ]4 NW. 1/4 sec. 9, T. 27 N., R. 1 E., as follows: Ft. in. Soil, brown 8 Sand, very fine-grained, clayey, brown, noncalcareous (sample 27) 2 Silt, clayey, brown, noncalcareous, base concealed 5 The sieve analysis of sample 27 (table 13, p. 48) shows the sand to be similar in grain size to the Albany No. grade al- though a little lower in content of 270-mesh grains. The sample contains 30.2 per cent A.F.A. clay which is a little more than in the Albany sand. The clay content of this sand increases toward the base, so by taking only the upper 1]/^ feet a material with a lower clay content could be produced. This sand is similar in grain size to that sampled near Rice (p. 22), about two miles south- east, which was classified as a No. 00 grade because of the greater percentage of pan material. Some of the sand in the Aiken terrace may be as fine grained as the Albany No. 00 sand. According to Littlefield,^-^ 3 to 4i/^ feet of sand was worked in the pit west of Aiken. The upper 3 feet (sample 61, table 12, p. 46) was reported to be finer grained and heavier than the lower II/2 ^^et (sample 62, table 12). The tests show that the "Littlefield. M. S., op. cit. pp. 117-118. 28 FINE-GRAINED MOLDING SAND R.3E. R.4 E. R. 4 E. R.5E. ILLINOIS STATE GEOLOGICAL SURVCY R.3E. R.4E. R.4 E. R.5E. Fig. 3. — Locations of samples collected in western Whiteside County. upper 3 feet has a grain size similar to that of sample 27. The sand is similar to the Albany No. grade but is a little lower in content of 270-mesh grains and a little higher in content of 200-mesh grains. The sample has a permeability of 12.2 at 6 per cent water which is equal to that of the average Albany No. sand. The surface of the terrace has an eleva- tion of 640 to 660 feet, about 50 feet above the Mississippi River bottoms. It occurs in the NW. 1/4 sec. 9, and NE. \/^ sec. 8, T. 27 N., R. 1 E. but is broken by a short gap about a quarter of a mile west of Aiken. Prospecting by test pits or auger borings is necessary to determine how much of the ter- race is underlain by sand. The terrace is crossed by the Chicago Great Western Railroad. Deposit near Milan, Rock Island County Fine-grained sand similar to the Albany No. grade underlies a terrace area about two miles west of Milan. Littlefield^* "Littlefield, M.S., op. cit. p. 138. ALBANY TYPE NO. GRADE 29 sampled 3]/ feet of fine yellow sand in the SW. cor. SW. ]4 SE. 14'sec. 22, T. 17 N., R. 2 W. The sample (110, table 12, p. 46) in grain size is similar to the Albany No. grade although it is a little higher in con- tent of 70- and 100-mesh grains. It has a very low permeability. Littlefield states, "It is not probable that this deposit con- tains more than 10,000 tons but the near- ness of a market and the adjacent railroad should stimulate prospecting in the vicin- ity." The area is along the Chicago, Rock Island and Pacific Railroad. Deposit near Lyndon, Whiteside County Sand similar to the Albany No. grade sand occurs in a ridge-like hill along the south side of the Langdon school, 2i/ miles northeast of Lyndon and about five miles south of Morrison (fig. 3). The sand is exposed in a road cut of State Highway No. 78 at the center of sec. 7, T. 20 N., R. 5 E. The road cut is badly slumped but the following beds were exposed by digging a deep channel in the east face below the crest of the hill : Ft. in. Soil, brown 1 Silt, very clayey, brown 1 Silt, clayey, brown (sample 26) .... 3 Sand, very fine-grained, slightly silty and clayey especially in upper part, brownish-gray, non- calcareous (sample 25) 4 Sand, similar to that above but con- taining slightly less clay and silt, lower part faintlv calcareous (sample 25B) '. 3 6 Sand, similar to above but highly calcareous, base not reached 6 The lower 2 feet of this section occurs below the level of the highway and was obtained in an auger boring. Tests on sample 25 (table 9, p. 24) show that in grain size this material is very close to the average of the Albany No. grade. It is a little lower in the amount retained on the 270-mesh sieve and a little higher in the amount retained on the 100-mesh sieve. Its grain fineness num- ber of 192 is typical of the No. grade sands. The sand contains only 6 per cent A.F.A. clay which is a little less than in the Albany sands of this grade. This is probably a desirable characteristic because the bonding strength of the clay appears to be higher in the Illinois sand than in the Albany sand. If a higher clay content is desired, it can easily be obtained by includ- ing a little of the overlying clayey silt. A sample (25A, table 13, p. 48) representing 6 inches of the overlying material and the upper 3]/? feet of the sand from which sample 25 was taken, contained 12 per cent of A.F.A. clay. The permeability of sample 25 shows remarkably little change with variation in the moisture content. The sample had a permeability of 16.1 at 3.5 per cent water and 16.6 at 7.6 per cent water. The per- meability is higher than the average for the Albany No. grade. The sand has a green compressive strength of 7.5 pounds per square inch at 5.5 per cent water. Sample 25B represents 3 feet 6 inches of sand, the lower part of which is slightly cal- careous. The sieve analysis (table 13) shows it is slightly coarser grained than sample 25 although the difference is prin- cipally in the much lower amount of pan material and the lower percentage of clay. It has the grain size of an Albany No. 1 grade sand but would require the addition of some bonding material. The bond could be obtained by adding some of the clayey silt represented by sample 26. If about 25 per cent of sample 26 were mixed with the sand it would contain about 13 per cent clay and could be classified as either a coarse- grained No. grade or a fine-grained No. 1 sand. This sand may contain too much calcium carbonate to be used as an Albany type sand. However, sands containing a greater amount of carbonates have been used, and it is possible that a market for this sand could be found, especially if it could be produced cheaply after removal of the overlying sand. Sample 26 might be used as a Southern Indiana type sand (p. 45) although its high clay content places it at a disadvantage in comparison with other sands of Southern Indiana type in the same general area. The sieve test of sample 26 is given in table 13. The hill from which the above samples were collected is about 20 feet high, 200 to 300 feet wide, and nearly half a mile long. Fine-grained sand is exposed in sev- eral road cuts in nearby hills. Similar hills occur in sections 7, 8, 17, and 18, T. 20 N., R. 5 E., and it is possible that many of them 30 FINE-GRAINED MOLDING SAND contain fine-grained sand. Variations in the grain size of the materials composing these hills is to be expected and thorough pros- pecting is necessary to establish the presence of a large enough quantity of suitable sand to warrant a commercial operation. The deposit sampled is a little more than two miles north of the Chicago, Burling- ton and Quincy Railroad. Deposit near Denrock, Whiteside County Fine-grained sand is exposed at many places in a large terrace about half a mile northeast of Denrock and two miles west of Lyndon. A large part of the sand in this area appears to be similar to the Albany No. grade. No. 1 grade sand is also pres- ent and possibly No. 00 grade sand. The sand is exposed in road cuts and was pene- trated in several auger borings. The loca- tions where the samples were collected are shown in figure 3. In the north part of the area the sand is exposed in the road cut on the south side of the road in the NW. i/J NE. ]4 NW. 1/4 sec. 18, T. 20 N., R. 5 E., as follows: Ft. in. Soil, brown 6 Sand, very fine-grained, silty, brown, noncalcareous, (sample 38)... ._ 2 4 Sand, similar to above but slightly more clayey, noncalcareous 2 Silt, light brown, calcareous 3 Sand, coarse, pebbly, calcareous, base concealed 5 Half a mile south of the above outcrop an auger boring near the edge of the ter- race, a quarter of a mile west of State Highway No. 78, in the NW. i/J NE. ]4 SW. 1/4 sec. 18, T. 20 N., R. 5 E., pene- trated the following beds: Ft. in. Soil, brownish-gray 6 Sand, very fine-grained, brown (sample 67A) 1 6 Silt, clayey, sandy, light brown, noncalcareous (sample 67B) 4 3 Silt, more clayey than above, tough, noncalcareous 6 Sand, medium- to coarse-grained, light gray, calcareous, base not reached 3 A quarter of a mile east of the auger bor- ing just described another boring was made along State Highway No. 78 near the NE. cor. SW. 1/4 sec. 18, T. 20 N., R. 5 E., and the following beds were penetrated : Ft. in. Soil, brownish-gray 6 Silt, sandy, clayey, brown (sample 68A) 5 6 Sand, fine-grained, weakly bonded, light brown, noncalcareous (sam- ple 68B) 4 6 Sand, similar to above but faintly calcareous, base not reached. ... 6 A quarter of a mile south of the auger boring just described the sand is exposed in a shallow road cut along the east side of State Highway No. 78, in the SW. ]4 NW. 1/4 SE. 1/4 sec. 18, T. 20 N., R. 5 E., as follows: Ft. in. Soil, sandy, dark brown 1 6 Silt, clayey, sandv, brown (sample 69A) ..' 2 Sand, fine-grained, light brownish- gray, noncalcareous (sample 69B) 3 Sand, similar to above but faintly calcareous, base concealed 1 Nearly a mile farther south fine-grained sand is exposed in a road cut of State High- way No. 2 near the margin of the terrace, in the NE. 14 NE. ^ SW. i/4 sec. 19, T. 20 N., R. 5 E. The road cut is badly slumped and the following beds were pene- trated in an auger boring on the south side of the road, about 150 feet east of the edge of the terrace : Ft. in. Soil, black 8 Sand, very fine-grained, light brown, noncalcareous (sample 65A)... 2 6 Sand, similar to above but slightly more clayey (sample 65B) 1 10 Silt, clayey, brown, noncalcareous, base not reached (sample 65C). . 6 The silt at the base of this boring over- lies a fine-grained sandy gravel. Sample 65AB represents the interval cov- ered by samples 65A and 65B in the above boring. About half a mile east of the boring just described an auger boring on the east side of the road, north of the railroad, in the NW. i/i SW. 14 SW. 14 sec. 20, T. 20 N., R. 5 E., penetrated the following beds: ALBANY TYPE NO. GRADE 31 Ft. in. Soil, black 8 Silt, clayey, brown, noncalcareous (sample 66) 4 6 Clay, silty, tough, noncalcareous. . . 4 Silt, sandy, mottled light and dark brown, noncalcareous, base not reached 1 6 Three samples (38, 65 AB, and 67 A) collected along the margin of the terrace are similar in grain size to the Albany No. grade sand. This sand overlies a sandy clayey silt (samples 65C and 67B) that may be a Southern Indiana type sand (p. 45) although it is higher in clay content than is usual for those sands. Along the western margin of the terrace the silt over- lies coarse sand and gravel but farther east along State Highway No. 78 it or a similar silt (samples 68 A and 69A) overlies sand (samples 68B and 69B) similar to the Al- bany No. 1 grade although weakly bonded. Tests of samples 38 and 65AB are given in table 9 (p. 24) and sieve analyses of the other samples are given in table 13 (p. 48). Sample 38 has a grain size similar to that of the Albany No. grade although it might also be used as a coarse-grained No. 00 grade sand. Its grain fineness num- ber of 222 classifies it as either a No. or a No. 00 grade sand. It differs from the No. grade only in being a little lower in sand retained on the 270-mesh sieve. Its clay content is close to the upper limit for the grade, and consequently it has a com- paratively high compressive strength. Its permeability of 10.4 at 7.5 per cent water is a little below the average of the Albany No. sand but is above the average for the No. 00 grade. Sample 65AB is also a No. grade sand but is a little coarser grained than Sample 38. It has a little more sand on the 100- mesh sieve and less on the 270-mesh sieve than the Albany No. sand. Its grain fine- ness number of 192 is typical of the coarser grained No. grade sands. This sample contains a little less clay than sample 38 and consequently it is not quite as strong and has a higher permeability. Its perme- ability is about equal to the average for the Albany No. grade sands. Sand with a grain size similar to that described is also exposed in other road cuts in the area and it appears that a large quantity of fine-grained sand is available. The area from which these samples were collected is more than 1]/? miles long and at least a quarter of a mile wide. The ter- race extends east of State Highway No. 78 as far as Lyndon and fine-grained sand may underlie part of that area. The Den- rock area is directly south of the Lyndon area in which fine-grained sand occurs in hills. The two areas may overlap. Detailed prospecting is necessary to prove that the area can support a commercial operation. However, judging by the out- crops and tests, the area can probably sup- ply large quantities of Nos. and 1 sands, and a smaller amount of No. 00 sand. It may be necessary to add bond clay to the No. 1 grade sand. The grades of sand can be somewhat controlled by varying the depth of sand worked. For example, sample 65AB represents about 4 feet 4 inches of sand which was slightly finer grained in the lower part. The upper 2 feet 6 inches (sample 65 A) in grain size is similar to the coarser sands of the Albany No. grade, whereas the lower 1 foot 10 inches (sample 65 B) is only slightly coarser grained than some of the Albany No. 00 sands. The deposits in this area are similar to the Albany deposits which also commonly contain several grades of sand in compara- tively small areas. Although this adds to the difficulty in grading, it adds to the num- ber of uses for which sands can be supplied from one pit. If it were desired to pro- duce a coarser sand in order to supply a still wider range of uses, much coarser sands than those described are available nearby. Coarse sand occurs in the flat low- land west of the terrace and sample 70 (table 13, p. 48) represents about 3 feet of sand exposed along the secondary road in the NE. 1/4 SE. 14 NE. 14 sec. 14, T. 20 N., R. 4 E. The sample is as coarse grained as the Albany No. 3 grade ; 85 per cent is coarser than a 100-mesh sieve. The sample contains only 4.6 per cent A.F.A. clay and probably would require the addi- tion of bond clay. The south end of the area is crossed by the Chicago, Burlington and Quincy Rail- road. 32 FINE-GRAINED MOLDING SAND ALBANY TYPE NO. 1 GRADE 33 Deposit near Morrison, Whiteside County Fine-grained sand underlies a terrace area along French Creek, about one mile east of Morrison. The sand is exposed in a cut bank along the creek south of U. S. Highway No. 30, in the NE. ]4 SW. ]4 SW. 14 sec. 16, T. 21 N., R. 5 E., as fol- lows : Ft. in. Soil, dark brown 10-12 Sand, very fine-grained, silty, brown, noncalcareous (sample 75) 2 8 Sand, fine-grained, brownish-gray, calcareous, base concealed 10 Sample 75 (table 13, p. 48) has a grain fineness number of 228 which classifies it as an Albany No. type sand or a coarse- grained No. 00 sand. However, in grada- tion of the sand it differs in several respects from the Albany sand. It has a little higher percentage of grains on the 65- and 100- mesh sieves and in the pan and a relatively low percentage between the 100- and 270- mesh sieves. The sand is intermediate in character between the Albany and South- ern Indiana sands. Its permeability is prob- ably low for an Albany sand and high for a Southern Indiana sand. The size of this deposit is uncertain and prospecting is necessary to determine wheth- er it is large enough to justify development. The exposure of sand is in a comparatively small remnant of the terrace but other areas at about the same elevation in this general vicinity may contain similar sands. The area is near the Chicago and North- w^estern Railway. Deposit near Union Grove, Whiteside County Fine-grained sand is exposed in a road cut about one mile southwest of Union Grove near the NE. cor. SE. i/i SW. i/i sec. 32, T. 22 N., R. 4 E., as follows: Ft. in. Soil, dark brown 9 Sand, fine-grained, silty, dark brownish-grav, noncalcareous (sample 82j . .'. 2 9 Sand, medium-grained, noncalcar- eous, base concealed 1 Sample 82 (table 13, p. 48) is similar in grain size to the Albany No. grade. It is lower in grains retained on the 270- mesh sieve and a little higher in grains on the 100-mesh sieve. It contains a little more A.F.A. clay than the Albany sands. The deposit occurs in a low hill on the upland. As road cuts in this general area indicate that the materials are variable in character, careful prospecting is needed to determine the quantity and quality of the sand available. The area is about one mile south of the Chicago and Northwestern Railway. Albany Type No. 1 Grade Deposit at Lansing, Cook County The finest grained sand found in the Chicago area occurs south of Chicago be- tween Lansing and Thornton. The sand in this area, although differing in several respects from the Albany sand, is most nearly like the Albany No. 1 grade. The sand has several characteristics which may enable it to meet the requirements for some uses where Albany sand is now employed. Its location in the Chicago district is ad- vantageous and would probably justify the cost of processing or blending with other sands if this were necessary to produce a sand that could compete with the Albany sands. The sand is exposed in ditches along the roads and was penetrated in several auger borings in the area shown in figure 4. The sand is exposed in a ditch at the SW. cor. sec. 36, T. 36 N., R. 14 E., as follows: Ft. 8-12 Soil, black, very sandy Sand, fine-grained, light yellowish- brown at top, reddish-brown at base, noncalcareous (sample 63A) 2 4 Sand, fine-grained, light brownish- gray, noncalcareous; slightly coarser grained and not as well bonded as above (sample 63B). . 8 Sand, similar to above but light gray, calcareous, base concealed. 4 Sample 63 is a combination of samples 63A and 63B. The beds exposed in a ditch in the NW. 14 NW. 14 NE. 1/4 sec. 2, T. 35 N., R. 14 E., are as follows: 34 FINE-GRAINED MOLDING SAND Ft. in. Soil, black, sandy 6-8 Sand, fine-grained, mostly reddish- brown; the upper 1 foot a little finer grained than the lower 3 feet; a slightly greater clay con- tent in a zone from 1 to 2 feet below the top (sample 98) 4 4 Sand, fine-grained, gray with black streaks, faintly calcareous, base concealed 6 In an auger boring at the southeast cor- ner of sec. 31, T. 36 N., R. 15 E., the following beds were penetrated: Ft. Soil, brown, sandy 4 Sand, fine-grained, slightly clayey, brown (sample 12) 1 2 Sand, fine-grained, yellow, noncal- careous; contains very little clay; auger hit large pebble at base. .. . 2 4 The following beds are exposed in a ditch along the road at the road "T" in the SW. 1/4 SW. 14 SW. 14 sec. 35, T. 36 N., R. 14 E.: Ft. in. Soil, dark brown, sandy 6 Sand, fine-grained, yellowish- brown, noncalcareous, base con- cealed (sample 106) 2 The sieve analyses, green compression, and permeability tests of samples 63 and 98 are given in table 9 (p. 24), and the sieve analyses of the remaining samples are given in table 13 (p. 48). The sand has a grain-size gradation unlike the Albany grades although nearest to the Albany No. 1 grade. It has a high percentage of grains on the 140-mesh sieve, usually more than 50 per cent, and about 75 per cent of the sand is retained on the 100- and 140-mesh sieves. In this it differs from the Albany No. 1 grade which has the sand well dis- tributed between these sieve sizes and the 200-mesh, 270-mesh and pan material. The percentage of grains coarser than the 70- mesh sieve is lower in this sand than is common in the Albany No. 1 grade al- though its grain fineness number which ranges from 98 to 113 classifies it as a No. lj/2 or a No. 2 grade. The high concen- tration of the grains on two adjacent sieves gives an open texture and an unusually high permeability. The two samples tested (63 and 98) have permeabilities from 50 to 60 which is average for the Albany No. 2 grade sands. The samples are weakly bond- ed and would require the addition of clay to give them strength. A sample to which 10 per cent of a local silty clay was added (sample 63-62, table 9) has a permeability of 48 which is high for a No. lyz grade sand. This sand, therefore, appears to be sufficiently fine grained to give castings the finish of an Albany No. 1 grade sand al- though open enough to have the venting characteristics of a No. 2 grade sand. As mentioned, most of this sand appears to be deficient in bond, containing from 5 to 8 per cent A.F.A. clay. One sample (12) contains 14 per cent A.F.A, clay but represents only the upper one foot of the deposit which is usually more strongly bond- ed than the lower part. A sand with suffi- cient strength might be produced if only the upper 1 to 2 feet of sand is used. This upper sand is not only better bonded but is slightly finer grained than the lower part of the sand. The compressive strength of the sand can be increased by adding a small amount of bentonite or fireclay bonding clay. The effect on the properties of the sand by bond- ing with the clay available near the deposit is shown by tests of sample 63-62 (table 9). This sample is a mixture of 90 per cent of sample 63 described above and 10 per cent of sample 62 (table 13). Sample 62 is principally A.F.A. clay with a small amount of pan material and sand. Use of this ma- terial as a bond affects the average grain size of the sand only slightly. Sample 63 has a grain fineness number of 104 and the mixture of the two samples (sample 63-62) has a grain fineness number of 109. The addition of 10 per cent of the local clay gave the sand, at 5.1 per cent water, a green compressive strength of 7.6 pounds per square inch and a permeability of 48.2. Sample 62 represents 2 feet 6 inches of noncalcareous silty clay directly below the soil and overlying a calcareous silty clay. It was collected from an auger boring about four miles southwest of Lansing, near Chi- cago Heights, at the SE. cor. NE. 14 sec. 16, T. 35 N., R. 14 E. Similar material is exposed along North Creek and in ditches along the roads at many places in the area immediately south of the sand deposits. Where overlain by sand the clay has been protected from weathering and is all or nearly all calcareous. ALBANY TYPE XO. 1 GRADE 35 It is possible that this clay could be pro- duced as a bond clay for general use. Be- cause of its favorable location, thin over- burden, and ease of mining, it might be produced at relatively low cost. However, more of this clay is required to bond the sand than of the standard bonding clays. Its bonding power would be increased if the sand and silt were removed but this additional processing might make the cost prohibitive. Further tests are needed to determine the effect of this clay on other properties of the sand such as durability. The clay minerals, however, appear to be the same as those in the natural-bonded sands of northern Illinois. Blending sample 63 with an equal amount of sample 38, a Whiteside County No. grade sand which has a high green compressive strength, gives the results shown in tests of sample 63-38 (table 9). The addition of the fine-grained sand gives the mixture a grain fineness number of 159 which classifies it as a Xo. 1 grade sand, although it is a little lower in content of grains on the 270-mesh sieve. The mix- ture, at 8.3 per cent water, has a green com- pressive strength of 7.5 pounds per square inch, and a permeability of 22.3. The permeability is slightly above the average for a No. 1 grade sand. When sample 63 is blended with 25 per cent of a Southern Indiana type sand (sample 36) the mixture has the charac- teristics shown by tests of sample 63-36 (table 9). The mixture has a grain fine- ness number of 141 and could be classified as a No. l]/2 grade sand or possibly as a coarse-grained No. 1 sand. It is lower in 200- and 270-mesh sand and higher in 140- mesh sand than most of the Albany No. 1 grade sands. At 6.4 per cent water the mixture has a green compressive strength of 5.7 pounds per square inch and a perme- ability of 29.9. Addition of a little more of sample 36 would increase the strength and probably not lower the permeability below that of an average No. 1 1/ grade sand. The most favorable part of the Lansing area for prospecting for fine-grained sand is shown in figure 4. The fine-grained sand occurs in the low area along the south side of a sand ridge which extends from the Illinois-Indiana state line through Lansing to Thornton. The extent of the fine- grained sand can be determined only by auger borings or test pits although in the S. yz sec. 36 the south margin of the area underlain by sand is marked by a distinct southward slope to a lower area which is underlain by clay. This topographic break is close to the position of the 615-foot con- tour as shown by the topographic map. The north boundary of the area is less distinct, as the fine-grained sand probably grades into the coarser sand of the higher area. It probably coincides generally with the base of the slope of the sand ridge, which is usually at about the position of the 620-foot contour although locally higher than that. Sand only slightly coarser grained than that described occurs in a narrow ridge which is a southward branch of the main sand ridge (fig. 4). The sand is exposed in a road cut near the NW. cor. SW. 14 sec. 36. T. 36 N., R. 14 E. About 5 feet of sand overlain by 6 inches of dark gray sandy soil is exposed above the level of the road. The sand is light yellowish brown at the top and lighter colored toward the base. It is noncalcareous and has very little bond. It probably extends 2 to 4 feet be- low the base of the outcrop to the level of the surrounding lower land but the lower part might be calcareous. A sample of the sand (64) differs from the sand in the area south of the ridge only in having about 10 per cent more sand retained on the 100- mesh sieve and about 10 per cent more on the 140-mesh sieve. It contains only 2.4 per cent A.F.A. clay and would require the addition of bond clay for making molds. It might be used in its natural state as a fine-grained core sand. This ridge is nearly half a mile long but only about 200 feet wide. Two parallel somewhat longer ridges occur just west of this ridge and may contain similar sand. The sand ridge about half a mile west in the center of the W. 1 ^ sec. 35 may also contain fine-grained sand. The sand composing the major part of the ridge north of the deposits described is coarser grained than the Albany sands considered in this investigation. Most of this sand contains 75 per cent or more of grains retained on the 100-mesh sieve, and it contains very little bond. Sample 110 (table 13) was collected from a small pit in Lansing. A similar ridge is about two miles south, extending southeast from Glen- wood, and another is about three miles 36 FINE-GRAINED MOLDING SAND north, near Calumet City. Sample 109 (table 13) was collected from the ridge near Calumet City. No fine-grained sand was found along these ridges although a few auger borings were made near them. Because it is near Chicago the land in which the fine-grained sand occurs may be comparatively high priced. Some of the area is used for truck gardening, but a large part of it, especially that in sec. 35 (fig. 4), is farm land. In digging molding sand it is usually possible to overcast the soil over- burden into the mined-out area so that the land can be used for agricultural purposes after the sand has been removed. Such a procedure would be practical in this area because it is relatively high and would not be excavated to water level. At most places the molding sand overlies calcareous sand which would be left and would provide drainage. Certain parts of the area may not be available for development. At Lansing a small part of the area has been subdivided into lots and the area south of 183d street is a Forest Preserve. The east part of the area is crossed by the Pennsylvania and Grand Trunk Rail- roads and the Chicago and Eastern Illinois Railroad is about one mile west of the area. Deposit near Colona, Henry County Sand occurs in low dunes on a large ter- race south of Colona in the lower part of Green River valley at its junction with Rock River. Some of the sand is similar to the coarser sands of the Albany No. 1 grade although much of the sand is somewhat coarser grained. Where exposed in a road cut along U. S. Highway No. 6 in the SE. 14 SE. 1/4 SW. 14 sec. 11, T. 17 N., R. 1 E., the sand is as follows: Ft. in. Soil, dark gray 8 Sand, fine-grained, slightly clayey, brownish-gray, noncalcareous (sample 45) 1 4 Sand, similar to above but contains little clay, base concealed 2 The sieve analysis of sample 45 (table 13, p. 48) shows that at this particular place the sand is a little too coarse grained to be classified as an Albany No. 1 grade. How- ever, Littlefield^"' collected three samples from the SW. 14 sec. 1 1, T. 17 N., R. 1 E., one of which was coarse grained, one (sample 94) was similar to sample 45, an- other (sample 95) was similar to the Al- bany No. 1 grade, although a little lower in content of grains retained on the 270- mesh sieve and of pan material. Tests of samples 94 and 95 are given in table 12 (p. 46). According to Littlefield the thickness of the workable sand ranges from 1 to 3 feet and the samples represent producible grades. The amount of sand available is probably hundreds of thousands of tons. The terrace on which these deposits oc- cur has an elevation of 580 to 600 feet and its surface is about 20 feet above Green River. The extent of the terrace areas is shown on the soil map of Henry County.^ ^' The area is crossed by the Chicago, Bur- lington, and Quincy Railroad. Deposit near Aiken, Jo Daviess County A terrace along the east side of Missis- sippi valley near Aiken (fig. 2, p. 23) four miles south of Galena, is underlain by sand that is similar in grain size to the Albany No. 1 grade. The sand is exposed in a road cut east of the Chicago, Burlington, and Quincy Railroad in the SE. 14 NW. 4 SW. 4 sec. 9, T. 27 N., R. 1 E., as follows: Ft. in. Soil, dark brown 8 Sand, fine-grained, reddish-brown, noncalcareous; the lower 1 foot a little more clavev than above (sample 28A). ... .'. 2 10 An auger boring below this outcrop pene- trated the following beds : Ft. in. Sand, fine-grained, reddish-brown, noncalcareous (sample 28B) 2 6 Sand, very fine-grained, brownish- gray; less clayey than above (sample 28C) 1 6 Sand and silt interbedded, noncal- careous; auger hit boulder or bedrock at base 8 i^Littlefield, M. S., op. cit., p. 116. i^Smith, R. S., DeTurk, E. E., Bauer. F. C, and Smith. L. H., Henry County Soils: Univ. Illinois Agri. Exper. Station Soil Report no. 41, 1928. ALBANY TYPE NO. 1 GRADE 37 A little more than a quarter of a mile southeast the sand is poorly exposed in an excavation along the southwest side of the railroad near the center of the SE. i/; SW. 1/4 sec. 9, T. 27 N., R. 1 E. An auger boring near the excavation penetrated the following beds: Ft. in. Soil, dark brown 6 Sand, fine-grained, dark brown, clayey (sample 78A) 2 9 Sand, very clayey 3 Sand, fine-grained, brownish-gray, more clayey at base (sample 78B) 3 Silt, sandy, clayey, noncalcareous, base concealed 6 Sieve analyses of the samples referred to above are given in table 13 (p. 48). All of the samples have a grain size very close to that of the Albany No. 1 sands although all are a little lower in content of grains retained on the 270-mesh sieve. In the road cut, the lower 1 foot 6 inches of the sand (sample 28C) is less strongly bonded than the upper 5 feet 4 inches. The uni- formity of the sand is shown by the averages of the samples obtained at each locality (table 10). Table 10. — Average Analyses of Samples FROM Terrace South of Aiken Retained on sieve number Samples 28A, 28B, 28C Samples 78A, 78B 30 40 50 70 100 140 200 270 Pan Clav Trace 0.5 2.2 4.1 15.8 17.0 15.9 6.9 24.5 13.6 162 Trace 0.3 1.8 4.5 17.9 17.7 15.4 3.2 26.1 12.9 Grain fineness number. . 161 The most promising area in which to prospect for fine-grained sand is in the terrace along the Chicago, Burlington, and Quincy Railroad (fig. 4). The terrace has an elevation of 600 to 620 feet and extends southeast from Smallpox Creek for about I14 miles. It is from an eighth to a quarter of a mile wide. The samples tested were collected near the northwest end of the ter- race and the character of the deposits farther southeast will have to be determined by test pits or auger borings. Some medium- and coarse-grained sands are exposed at the south end of the terrace and it is possible that the fine-grained sands are not present there or are covered by the coarser sands. Deposits near Mason City, Mason County A large area north and west of Mason City is underlain by sand, some of which is similar in grain size to the Albany No. 1 grade. Most of the sand exposed is a little coarser grained than the No. 1 grade. The locations near Mason City where the sam- ples were collected are shown in figure 5. Sand similar to the No. 1 grade is ex- posed in a road cut about one mile north of Mason City along State Highway No. 24, about 50 yards south of the NW. cor. sec. 5, T. 20 N., R. 5 W., as follows: Ft. in. Soil, sandy, black 1 Sand, fine-grained, dark gray, non- calcareous (sample 52) 2 6 Sand, fine-grained, brown, noncal- careous (sample 51) 2 Sand, fine-grained, light yellowish- brown, calcareous, base concealed. 6 Sand of a similar character is exposed in a road cut along State Highway No. 10, iy> miles west of Mason City, in the SE. 14 SW. 1/4 SE. 14 sec. 2, T. 20 N., R. 6 W., as follows: Ft. in. Soil, sandy, dark gray 1 Sand, fine-grained, clayey, dark brownish - gray, noncalcareous (sample 96x'\) . 3 Sand, fine-grained, light yellowish- brown, noncalcareous (sample 96B) ._ 3 Sand, fine-grained, yellowish-gray, calcareous 6 The lower 2 feet was penetrated in an auger boring. All of the samples described above are Albany No. 1 grade sands except sample 96B which might better be classed as a No. sand although it is close to the boundary between the No. and No. 1 grade sands. Tests on samples 51 and 96A are given in table 9 (p 24), and sieve analyses of samples 52 and 96B are given in table 13 (p. 48). Sample 51 is similar in grain size 38 FINE-GRAINED MOLDING SAND O LOCATION OF SAMPLE R.6 W. R . 5 W. SAND DEPOSITS COMMON NORTH q i^ OF THIS LINE ' ^ SCALE I 2 3 MILES Fig. 5 — Locations of samples collected near Mason City in Mason County, to the average Albany No. 1 grade sand (table 2, p. 9). If 8 to 10 per cent of the pan material were retained on the 270- mesh sieve, the grain size would match the average for the grade very closely. The sample has a green permeability of 17.6 at 7.4 per cent water which is average for the No. 1 grade, and its green compressive strength of 7.4 pounds per square inch at 7.4 per cent water is also average. The overlying 2 feet 6 inches of sand (sample 52) is similar in grain size but contains a higher amount of A.F.A. clay than the lower sand. At least a part of the upper sand could probably be included with the lower sand without changing its properties appreciably. Sample 96A has a grain size similar to that of sample 51 but contains a higher percentage of A.F.A. clay. It has a satis- factory permeability of 27.9 at 7.6 per cent w^ater, but is higher than sample 51 in green compressive strength with 14 pounds per square inch at 7.6 per cent water. It con- tains enough organic matter to color it dark gray. The underlying sand (sample 96B) contains much less A.F.A. clay and would improve the upper sand if mixed with it. The sand in this area occurs in broad, low sand dunes. The sand is widespread but may be absent in some of the low areas between the dunes. Although the amount of sand of the Albany No. 1 type is un- certain, large quantities may be available inasmuch as similar sand is exposed in other road cuts in the area (samples 97A, 97B, table 13). It will be necessary to make auger borings or test pits to determine the size of the deposits. If the sand is uniform enough in these hills, it is probable that other nearby hills will also be found to contain workable deposits. The area north of Mason City is about half a mile from the Chicago and Alton Railroad, and the area west of Mason City is along the Illinois Central Railroad. Deposit near Garden Plain, Whiteside County Sand similar to the Albany No. 1 grade underlies a terrace about three miles south- east of Garden Plain along the west side of Cattail Slough. The surface of the ter- race is about 25 feet above the valley floor. The terrace extends along the valley for about three-quarters of a mile and has a maximum width of nearly one quarter of a mile. The locations where samples were collected are shown in figure 3 (p. 28). ALBANY TYPE NO. 1 GRADE 39 The sand is exposed in a road cut at a lane a short distance south of the railroad in the SE. 14 NE. ]4 NW. y^ sec. 32, T. 21 N., R. 4 E., as follows: Ft. in. Soil, sandy, dark gray 1 Sand, fine-grained, clayey, dark brown, noncalcareous (sample 39A) 2 6 Sand, similar to above but much less clayev, noncalcareous (sam- ple 39B).' 3 Silt, clayey, brown, noncalcareous, penetrated in auger boring, base not reached 1 About an eighth of a mile north of this section the sand is also exposed in a road cut along the north side of the road, 100 feet east of the railroad, in the SE. ]4. SE. 14 SW. 14 sec. 29, T. 21 N., R. 4 E., as follows : Ft. in. Soil, sandy, dark gray 1 Sand, clayey, brown; lower 2 feet slightly more clayev than above (sample 84A) 3 Sand, fine-grained, less clayey than above, brown, noncalcareous; lower 2 feet was penetrated in an auger boring (sample 84B) 5 Silt, brown, noncalcareous, base not reached 6 The tests of sample 39A are given in table 9 (p. 24), and the sieve analyses of samples 39B, 84A, and 84B are given in table 13, (p. 48). These samples are all similar in grain size to the Albany No. 1 grade. Sample 39A has a permeability of 22.4 at 8 per cent water which is above the average for Albany sands of that grade. The sample has a high green compressive strength of 13.8 pounds per square inch at 8 per cent water. The underlying sand (sample 39B) has a lower clay content but is otherwise similar in grain size. In- cluding it with the upper sand would re- duce the strength and increase the perme- ability. Samples 84A and 84B are similar in grain size to sample 39A but are slightly coarser grained. They are also a little lower in clay content but are well bonded. Littlefield^' also examined this deposit and collected two samples (68 and 69, table 12, p. 46) which had a grain size similar to that of samples 39A and 84B. The I'Littlefield. M. S., op. cit. p. 144 samples were reported to represent 2 to 3 feet of sand. Where sampled the terrace appears to contain from 5 to 8 feet of workable sand below an overburden of about 1 foot of soil. Prospecting by test pitting or auger boring is necessary to determine how large an area of the terrace is underlain by sand similar to that described. Judging from the similarity of the sand in the two road cuts, a considerable quantity of uniform sand is probably available. The area is crossed by the Chicago, Bur- lington and Quincy Railroad. Deposit near Fenton, Whiteside County Fine-grained sand occurs in low dunes along the west side of Cattail Slough, about two miles northwest of Fenton (fig. 3, p. 28). The dunes extend along the base of the bluffs for a little over half a mile. An auger boring on top of a hill on the east side of the road, about 100 yards south- east of the house near the SE. cor. NW. 14 sec. 4, T. 20 N., R. 4 E., penetrated the following materials : Ft. in. Soil, sandy, brownish-gray 6 Sand, fine-grained, light reddish- brown; noncalcareous Tsample 72)..... 5 6 Sand, similar to above but faintly calcareous; base not reached. ... 1 Tests of sample 72 are given in table 9 (p. 24). The sample is similar in grain size to the coarser grained sands included in the Albany No. 1 grade. It is lower in the percentage of grains retained on the 270-mesh sieve and a little higher in the percentage retained on the 100-mesh sieve than most No. 1 grade sands. Its grain fineness number of 140 is a little low for the No. 1 grade. The sand might be used also as a No. ly grade sand. However, it contains only 5 per cent sand coarser than the 70-mesh sieve which is average for the No. 1 grade, while the average No. I14 grade contains 20 per cent, and some have 30 per cent coarser than the 70-mesh sieve. The permeability of 24.4 at 6 per cent water is high for the No. 1 grade but a little below average for the No. \y? grade. If used at 7.9 per cent moisture, the sand would have a permeability of 29.5 which 40 FINE-GRAINED MOLDING SAND is average for the No. \]/i grade sands. The sand has an average green compressive strength. The area in which this sand occurs is about half a mile long and its width aver- ages about 200 yards. The sand is prob- ably from 10 to 20 feet thick but only the upper 4 to 6 feet is free from carbonates. Some of the lower sand may be low enough in carbonates to be suitable for some uses, but it may be deficient in bond. Few natural outcrops occur in the area and prospecting by auger borings or test pits is necessary to determine how much of the area is underlain by sand of the type sampled. The area is adjacent to the Chicago, Burlington and Quincy Railroad. Deposits at Round Grove, Whiteside County Fine-grained sand that may be Alban\ No. 1 grade occurs in a long ridge-like hill at Round Grove, about four miles east of Morrison in Whiteside County. This hill also contains sand similar to the Albany No. 00 grade and the general description of the area and the character of the sand exposed is given in the description of the No. 00 grade sand (p. 26). Sand similar to the Albany No. 1 grade was sampled in the road cut at Round Grove (sample 73A), where it represents Sy? feet of sand immediately below the soil. The sand differs from the Albany No. 1 grade in several respects. It is lower in content of grains on the 200- and 270- mesh sieves and is a little higher in grains retained on the 100-mesh sieve. However, it contains only 10 per cent of grains coarser than the 70-mesh sieve. This is less than some Albany No. 1 sands and considerably less than most No. ly? grade sands. The deficiency of the sand in the finer sieve sizes is in part counterbalanced by a slight excess of pan material which accounts for its having a grain fineness number of 166 which is that of an average No. 1 grade sand. This uneven gradation in grain size gives the sand an open texture. It has a permeability of 27.9 at 6.8 per cent water which is higher than that of the Albany No. 1 sands and about average for the No. \]/2 grade sands. Although the entire hill is probably un- derlain by sand, the greater part of the sand contains carbonates and therefore is not an Albany type sand. Only the sand in the weathered zone, from 4 to 6 feet thick, is free from carbonates. At least part of the hill is covered by several feet of clayey silt which has protected the sand from weathering. Consequently prospect- ing by means of auger borings or test pits is necessary to determine how large an area of suitable sand is available. The possible presence of similar sand in other nearbv hills is referred to elsewhere (p. 27). OTHER DEPOSITS In addition to the deposits from which the most promising samples of Albany type sands were collected, many other deposits were examined. As shown by the sieve analyses most of these sands differ in one or more respects from the Albany No. 00, No. 0, or No. 1 grade sands. Many of these sands are probably suitable for some foundry uses, perhaps even for uses where Albany sands are now employed. A large number of the samples are from deposits which were coarser grained than the Al- bany No. 1 sands and some of them are similar in grain size to the Albany No. 1 y> or Albany No. 2 sands. Some of the samples were found to contain too much A.F.A. clay. Others have a radically differ ent gradation from the Albany sands, most commonly being much too low in content of sand retained on the 200- and 270-mesh sieves. In the following pages the deposits not described elsewhere in more detail are dis- cussed by counties with brief reference to the way in which the samples differ from the Albany type sands. The sieve analysis, location, thickness sampled, thickness of overburden, and other information about each sample is given in table 13 (p. 48). These sieve analyses are probably repre- sentative of the finest grained sand avail- able in the areas discussed. A great many exposures were examined and usually sam- ples were collected from the finest sands exposed, although in some areas where it was evident that the sand was too coarse no samples were collected. It was not feasible to examine all the road cuts nor to drill auger borings in all the tracts under- ALBANY TYPE 41 lain by sand so it is possible that finer grained sands may be found in these areas by thorough prospecting. Cook County During Glacial times, the land now occu- pied by the City of Chicago and extensive areas surrounding the city were covered by a lake. Large quantities of sand accumu- lated along the shores of the lake but al- most all the sand now exposed in this area is much coarser grained than the Albany No. 1 grade sand. The finest grained sand found (deposit at Lansing, p. 33) occurs between an old shoreline and a sand ridge which was probably an oft-shore sand bar in the lake. Similar deposits might be found elsewhere near the old shorelines^'^ although several auger borings at favorable localities did not penetrate any fine-grained sand. Sample 11 (table 13) represents the finest grained sand found in several auger borings in the area between the sand ridge extending southeast from Glenwood and the old shoreline at Chicago Heights. It is coarser grained than the Albany No. 1 sand. A considerable area of the old lake bottom is underlain by silt deposits but the noncalcareous zone on these deposits is thin and the material is too clayey for use as a Southern Indiana type sand. Ford, Grundy, Iroquois, Kankakee, and Will Counties Large areas in these counties were cov- ered by lakes during the Glacial period and large areas of the old lake bottoms are underlain by sand. In many areas the sand has been blown into dunes, most of which are covered with a thin sandy soil and are now held in place by vegetation. The dis- tribution of the sandy areas is shown on the soil maps of these counties. ^'^ i**Locations of the shore lines are shown in the U. S. Geol. Survey Geologic Atlas, Chicago Folio (No. 81). 1902. isSmith. R. S., DeTurk. E. E., Bauer. F. C, Smith, L. H., Ford County soils: Univ. Illinois Agr. Exper. Sta- tion, Soil Report No. 54, 1933. Smith, R. S., DeTurk, E. E., Bauer. F. C, and Smith, L. H., Grundy County soils: Univ. Illinois Agr. Exper. Station. Soil Report Xo. 26, 1924. Mosier, J. G., Holt, S. V., Van Alstine, E., and Snider, H. J., Iroquois County soils: Univ. Illinois Agr. Exper. Station, Soil Report Xo. 22, 1922. Smith. R. S., Ellis, O. I.. DeTurk. E. E.. Bauer. F. C. and Smith. L. H.. Will County soils: Univ. Illinois Agr. Exper. Station. Soil Report Xo. 35. 1926. Hopkins. C. G.. Mosier. J. G.. Van Alstine. E.. Gar- rett, F. W., Kankakee County soils: Univ. Illinois Agr. Exper. Station, Soil Report Xo. 13, 1916. The sand deposits in these counties were examined at scores of places but almost without exception were coarser grained than the Albany No. 1 grade sand. At many places the sand is calcareous at a depth of 3 feet and the noncalcareous zone is too clayey as well as too thin to be generally valuable as molding sand. In some areas the soil itself has a grain size not greatly different from that of the Albany sands but it contains a large amount of organic matter including the undecomposed roots of plants. On the sand dunes the soil is thin and usually only a few inches of sand be- low the humus zone is well bonded. Below that the sand is sharp and incoherent. The upper few feet of the sand is usually non- calcareous and in places as much as 10 feet is noncalcareous. Descriptions of the samples and sieve analyses are given in table 13. The way in which they differ in grain size from the finer grained Albany sands are given below : Ford County. — The samples from Ford County are 2, 3AB. 3C, 3D. Sample 2 contains too much clay and has a large amount of organic material. The other samples are too coarse grained. Grundy County. — The following sam- ples were collected in Grundy County : 99 — Too coarse, clay content high. 100 — Too coarse. 101 — Too clayey; typical of noncalcare- ous zone on the silty clays which underlie most of the area; might be used for bonding some of the weaklv bonded sands. 102, 103, 107— Too coarse. Iroquois County. — The samples collected from Iroquois County are as follows: 4 — Too clayey and coarse. 5 — Too coarse. 6 and 6A — Too coarse; similar to sam- ples 55A, 55B, and 55C, but low in bond. 7 — Too clayey; low in sand retained on fine sieve sizes. 55A, 55B, and 55C — Too coarse; upper part contains too much clay, lower part, too little clay; average clay con- tent of all three samples is 20 per cent ; the average grain fineness number is 110, and the sand probably can be classified as a coarse-grained Albany No. 1 1/2 or a fine-grained Albany No. 2 sand ; this appears to be the finest 42 FINE-GRAINED MOLDING SAND grained sand available in the area, al- though sand of similar grain size oc- curs at several places. 56 — Similar to samples 55A, 55B, and 55C. 57 — Too coarse and clayey. 58A and 58B — Similar in grain size to samples 55A, 55B, and 55C, but lower in bond. 59, 60, 61— Similar to samples 55A, 55B, and 55C, but lower in bond. Ka?ikakee County. — The samples collect- ed in Kankakee County are 8, 9, and 10. These sands are too coarse grained but are the finest grained sands observed in the county. They are similar in grain size to samples 55A, 55B, and 55C in Iroquois County. Will Cow/7/>'.— Samples 104 and 105 were collected from Will County. Sample 104 was too coarse. Sample 105 is only a little too coarse for the No. 1 grade but the sand is overlain by till which is probably thick except at the outcrop. Henry County Much of the northern part of Henry County is underlain by sand but most of these deposits are coarser grained than the Albany No. 1 grade sand. The distribu- tion of the sandy areas is shown in the soil map of Henry County.^° Samples 47 and 48, collected from this area, represent the finest grained sand found except in the area near Colona (p. 36). Both samples have grain sizes similar to the Albany No. 1 y'z grade. Descriptions of the samples and sieve tests are given in table 13. Jo Daviess County In the vicinity of Blanding"\ about ten miles south of Galena on the east side of Mississippi Valley, several terraces occur at about the same levels as those described at Aiken (p. 36) and may contain sim- ilar deposits. The samples briefly described below were also collected from Jo Daviess County. Locations and sieve analyses are given in table 13. 20Smith, R. S., DeTurk, E. E., Bauer, F. C, and Smith, L. H., Henry County soils: Univ. Illinois Agr. Exper. Station, Soil Report No. 41, 1928. 2iThe extent of the terrace is shown in the following report: Trowbridge, A. C. and Shaw, E. W., Geology and Geography of the Galena and Elizabeth quadrangles, 111.: Illinois State Geol. Survey Bull. 26, Plate IV, 1916. 29 — Contains only about 15 per cent grains between 100- and 270-mesh sieves but its relatively high content of pan ma- terial gives this sample a grain fineness number of 161, similar to the Albany No. 1 grade sands (fig. 2, p. 23). 32 — Contains little bond; this sand is poorly exposed and it is doubtful if a large quantity is available. Mason County The greater part of Mason County-^ con- sists of a large terrace area along Illinois Valley. All the sand examined in the ter- race area is medium and coarse grained. The finest grained sand found in Mason Coun- ty occurs in the upland area in the south- east part of the county and has been de- scribed (Mason City area, p. 37). In addi- tion to the samples previously described, the other samples collected in the vicinity of Mason City (fig. 5, p. 38) are listed below w^ith brief comments on the manner in which they differ in grain size from the finer grained Albany sands. Locations and sieve analvses of the samples are given in table 13. ' 49 — Too clayey. 50 — Too coarse. 54 — Too coarse. 90 — Too clayey. 91 — Too coarse and clayey. 92A, 92B— Too clayey. 92C — Too coarse. 93 A, 93 B— Too clayey. 94A, 94B, 95A, 95B, 95C, 97A, 98B— Too coarse. Rock Island County Extensive deposits of sand occur in ter- races along Rock and Mississippi rivers in Rock Island County.-' Most of the sand examined on these terraces was much coars- er grained than the Albany No. 1 sand. Littlefield-* reports the production of a fine-grained molding sand from the Missis- sippi River flats southwest of Rock Island near the junction of Rock and Mississippi 22Smith, R. S., DeTurk. E. E., Bauer, F. C, and Smith, L. H., Mason County soils: Univ. Illinois Agr. Exper. Station, Soil Report No. 28, 1924. 23Savage, T. E., and Udden, J. A., Geology and mineral resources of the Edgington and Milan quadrangles. 111.: Illinois State Geol. Survey Bull. 38, Plate 2, 1922. Smith, R. S., Ellis, O. I., DeTurk, E. E., Bauer, F. C, and Smith, L. H., Rock Island County Soils: Univ. Illi- nois Agr. Exper. Station, Soil Report No. 31, 1925. 24Littlef^eld, M. S., op. cit., p. 137. SOUTHERN INDIANA TYPE 43 rivers. Tests of two samples (78, 79, table 12) show the sand is similar in grain size to the Albany No. 1 sand although lower in content of grains retained on the 270- mesh sieve. The permeability is low for a No. 1 grade sand. One sample had a large amount of organic bond. Sample 41 (table 13), collected from an auger boring near School No. 49, two miles northwest of Milan, was a little too coarse grained and also was high in content of A.F.A. clay for a No. 1 grade sand. Winnebago County Large areas of terraces along Rock River in Winnebago County-^ are underlain by sand, but that examined w^as nearly all medium or coarse grained. Similar sand also occurs in terraces along Pecatonica River. Sample 18 (table 13) represents the finest grained sand observed along Pecaton- ica River. It is too coarse grained and much lower in content of sand between the 100- and 270-mesh sieves than the Albany No. 1 sand. Sample 14 represents a sand deposit on the upland south of Pecatonica but it also is too coarse grained (table 13, p. 48). SOUTHERN INDIANA TYPE SANDS PROMISING DEPOSITS Sands of the Southern Indiana type usu- ally have a grain fineness number of more than 250 and contain from 5 to 30 per cent A.F.A. clay (p. 14). Of the samples col- lected, 37 have a grain fineness number higher than 250, but 20 of these have more than 30 per cent A.F.A. clay and two are calcareous, leaving 15 samples which meet the above requirements (table 6, p. 18). Fourteen of these samples were collected from the loess deposits in the Mississippi Valley bluffs and adjacent upland areas in Whiteside and Rock Island counties. One sample is from Jo Daviess County. Similar deposits are present in and near the Missis- sippi Valley bluffs almost continuously from East Dubuque to Rock Island and probably also farther south along Mississippi Valley. 25Bretz, J Harlen, Geology and mineral resources of the Kings quadrangle, III.: Illinois Geol. Survey Bull. 43, 1923. Hopkins. C. G., Mosier. J. G., Van Alstine, E., Gar- rett, F. W., Winnebago County soils: Univ. Illinois Agr. Exper. Station, Soil Report No. 12, 1916. The calcareous loess has been used for molding sand and was produced in pits near Rock Island and Galena. Because of the presence of carbonates not much of this ma- terial has been used and there is no con- sistent production. Samples of the calcar- eous loess from Rock Island and Galena are 63 and 102 respectively (table 12, p. 46). The following samples meet the grain size requirements for the Southern Indiana tvpe sands: 34, 35, 36, 36A, 37, 40, 42, 74, 77B, 80A, 80B, 81B, 86B, 87, 88B. The above samples are all similar in grain size except for variations in the amount of A.F.A. clay. Consequently green perme- ability and compressive strength tests were made on three samples which show the range in A.F.A. clay content commonly found in these deposits. The samples tested are 36, which had 23.2 per cent A.F.A. clay, 80A, which had 26.8 per cent A.F.A. clay, and 44, which had 30.4 per cent A.F.A. clay. These samples were collected at the localities described below. In a road cut about four miles north- east of Fulton at the top of the bluffs near the center of the NE. 14 sec. 19, T. 22 N., R. 4 E. (Whiteside County), the following beds are exposed: Ft. in. Silt, dark brown 1 Silt, sandy, brown, noncalcareous; the upper 1 foot 8 inches is more clayey than below (sample 36 represents the entire thickness, sample 36A, the lower 3 feet) .... 4 8 Silt, sandy, light yellowish-brown, calcareous, base concealed (sam- ple 36B from upper 3 feet) 5 In a road cut on the south side of U. S. Highway No. 30, three miles east of Fulton at the sharp curve in the road in the NW. 14 SW. 1/4 SE. 14 sec. 30, T. 22 N., R. 4 E., (Whiteside County) the following beds are exposed : Ft. in. Soil, brown 1 Silt, clavev, brown, noncalcareous (sample '80A) 5 Silt, similar to above but upper 2 feet slightly more clavey (sample 80B). . . ..' ' 3 6 Silt, brownish-gray, calcareous.... 1 Sand, light gray, medium-grained, calcareous, base concealed 2 The following beds are exposed about two miles northwest of Hillsdale in a road 44 FINE-GRAINED MOLDING SAND Table 11. — -Tests of Southern Indiana Type Sands from Northern Illinois Sample number County Sieve Analysis, Per Cent Retained ON Sieve Grain fine- ness num- ber Water (per cent) Per- mea- bility Green com- pres- sive 40 50 70 100 140 200 270 Pan Clay Total strength lbs. sq. in. 36 44 80A Whiteside Rock Island. . . Whiteside Tr Tr Tr Tr Tr Tr 0.2 Tr 0.2 0.4 0.2 0.2 0.8 0.4 0.4 2.2 1.4 1.4 1.8 3.0 2.0 71.4 64.6 69.0 23.2 30.4 26.8 100.0 100.0 100.0 289 291 292 5.0 6.6 8.0 4.3 6.1 6.9 8.6 3.9 6.1 8.6 4.3 6.5 5.9 1.7 4.3 5.8 9.9 2.4 4.9 6.5 18.2 14.8 12.6 22.0 16.1 16.8 13.9 21.5 18.1 14.0 cut at the top of a hill, 50 yards north of an angle in the road, in the SE. i/J SE. 14 NW. 14 sec. 18, T. 19 N., R. 3 E. (Rock Island County) : Ft. in. Soil, brown 8 Silt, clayey, brown, noncalcareous (sample 44) 3 9 Silt, light brown, calcareous, base concealed 3 The locations where samples 36 and 80A were collected are shown on figure 3 (p. 28). The tests of samples 36, 44, and 80A are given in table 11 (p. 44), and the sieve analyses of the other samples are given in table 13 (p. 48). The samples tested have a permeability as high as or a little higher than many of the Southern Indiana sands. The samples have a compressive strength higher than that of the sample of Southern Indiana sand tested (FS, table 4, p. 12). By far the greater part of the loess which mantles the bluffs and uplands near Missis- sippi Valley is highly calcareous and there- fore unsuited for many foundry uses. In these deposits, as in the Albany type sand deposits, weathering has leached the car- bonates from the upper 4 to 8 feet of the loess. In this zone the solutions percolating downward not only dissolve the carbonates but at the same time carry clay downward from the surface soil and deposit it in the upper part of the silt. As a result the non- calcareous zone, and especially the part immediately below the soil, contains more clay than the underlying calcareous mate- rial. In some of the deposits examined the calcareous, unweathered material contains a relatively low amount of A.F.A. clay, as sample 36B, which has 12.2 per cent A.F.A. clay, and sample 108, which has 15.6 per cent A.F.A. clay. The lower part of the noncalcareous zone usually contains from 15 to 25 per cent A.F.A. clay, and the upper 1 to 2 feet contains 5 to 15 per cent more A.F.A. clay. Therefore it may be desirable in working many deposits to omit the upper 1 to 2 feet below the soil, which would leave from 2 to 5 feet of noncal- careous silt with a relatively low A.F.A. clay content. A few samples representing the entire noncalcareous zone contain more than 40 per cent A.F.A. clay and at these places it is doubtful if a material with low^ clay content can be produced. The most promising areas are those shown on the soil maps of Whiteside'-" and Rock Island-' counties as mixed sand and loess, fine sandy loam, and fine sandy silt loam. These areas include the greater part of the upland areas within ten miles of the Missis- sippi River bluffs. Within these areas the deposits nearer the Mississippi bluffs appear to be slightly less clayey and more sandy, characteristics which are desirable to a cer- 26Smith, R. S., Ellis, O. I., DeTurk, E. E., Bauer, F. C, and Smith, L. H., Whiteside County soils: Univ. Illi- nois Agr. Exper. Station Soil report No. 40, 1928. 2'Smith, R. S., Ellis, O. I.. DeTurk, E. E., Bauer, F. C, and Smith, L. H., Rock Island County soils: Univ. Illinois Agr. Exper. Station Soil report No. 31, 1925. SOUTHERN INDIANA TYPE 45 tain extent as they tend to increase the permeability and decrease the strength of the sand. The similarity of the sieve analyses of the samples collected at widely separated places indicates that the material is fairly uniform in grain size. However, the need for carefully prospecting a proposed site for a commercial operation is shown by the presence in the uplands of areas where the silt is covered by medium-grained sand. Also, in some areas the noncalcareous zone is too high in A.F.A. clay content for a Southern Indiana type sand, and at others the zone with low A.F.A. clay content may be too thin or covered with a com- paratively thick overburden of silty clay. Many areas favorable for prospecting occur along the paved highways and along the railroads, especially the Chicago, Bur- lington and Quincy Railroad, east of Ful- ton, near Garden Plain, Hillsdale, and Barstow^; along the Chicago, Milwaukee and St. Paul Railroad near Albany, Port Byron, and Hampton; and along the Chi- cago and Northwestern Railroad east of Fulton, near Union Grove and Morrison. Similar deposits probably are present at many other places farther north near Sa- vanna in Carroll County, and near Galena in Jo Daviess County. OTHER DEPOSITS Some of the Albany type sand deposits described are overlain by several feet of noncalcareous silt which is similar to the Southern Indiana sand but contains more than 30 per cent A.F.A. clay. Although the typical Southern Indiana sands contain less than 30 per cent A.F.A. clay, many analyses have been published of sands con- taining more than 30 per cent A.F.A. clay, which have been produced on a commercial scale. Another possible use for these ma- terials is for blending with other sands deficient in bond. This use would be lim- ited to those sands to which adding silt, as well as the clay, would not be detrimental. Where sands high in clay content form the overburden on a valuable sand, and could be produced cheaply, it is possible that some outlet for them could be found in the foundry trade. Deposits of this kind are represented by samples 26 (overlying sample 25, p. 29) and 31 (overlying sample 30, p. 23). Other samples containing 30 to 40 per cent clay are 33, 43, 44, 65C, 67B, 68A, 77A, 79, 81A, 83, 86A, and 88A. Descrip- tions of these samples and their sieve an- alyses are given in table 13 (p. 48). These samples are all from the area near Missis- sippi Valley and most of them w^ere col- lected from the entire noncalcareous zone, omitting only the soil. Since a good many of them contain only slightly more than 30 per cent A.F.A. clay, it is probable that a material with less than 30 per cent A.F.A. clay can be produced if the upper clayey zone, or part of it immediately below the soil, is removed with the soil as overburden. A few samples from the same area repre- senting the entire noncalcareous zone con- tain over 40 per cent A.F.A. clay. It is doubtful if a material with low clay con- tent can be produced at the places where these samples were collected. Samples with more than 40 per cent A.F.A. clav are 66, 71, 85, and 89. The noncalcareous portion of the loess deposits examined farther east from Missis- sippi Valley is in all cases high in A.F.A. clay, usually more than 40 per cent. Sam- ples 20 and 22 (table 13) are typical of this material in Winnebago County. 46 FINE-GRAINED MOLDING SAND t^ 00 lO rf -^ t- CN NO r- H ro ro "^ CN CN NO ON-^t ONO --^ OO CN '— 1 t^ Tfi t^ t^ 1^ d(M'd On NOl:^ Tf 00 CO t^ CN Tj< lO CM CN lO CN NO Ol^ 0\ CO rr» ^ On 00 CN Lo ro '-H lO CN LO rci Tt T:t^t^ to t^ CN O Tf CN On ON ON ON C S^ fO CN CN CS T-< ,-1 CN CN CN CN CO to CN CN ■rt CN CN C/5 CN CN OS CN O 00 nOcO rJH CN CN PT) odo^d to Tt ON on' on' On' a^ O^ 00 O^ u O On Os On ON ON On ON 0\ ON -* o O 00 CN CN ■^ ■^ o > >. u rt on' 00 O^ NO 00 CN lO t^ d CN a: u Tf 00 OO 00 CN o NO o ■^ o r^ Tt' ON d ON NO d NO to Q CiH CN VO ro CO CN CN CN CN O o CN rt' O CN CN NO NO o O^ CN ^ LO r^ 00 od as to CN Tt^ o CN o O 00 o 00 00 1 NO irj r^ -* fO CO to CN t^ CN '"' CN CN CN *"" Tf o O rf 00 00 o to 'Tt^ Oh o 1-H O^ OO ^ CT) 00 CN t^ 00 ^ i ^-H T-H tH y—^ tH i 0^ o o lO O 00 o 00 ■* NO ^ 8 NO t- d 00 ^ rn d oi t^ CN ■^ "^ '"' »-i < > o NO ^ o o On CN ^ 00 O CN ro d ^ ^ en CN lO 00 Ui t^ CN »-( •^ c^ "* o es •^ >. c 3 O u -d -6 C/5 W3 c« c c 05 C/) (Zl > > "cfl "35 '35 '35 HI rt rt rt (U OJ «j 4J Q Q Q ^ Ic 1j5 15 u O o O •— > O *— > ^ ^ ^ ^ a> ti -7! "" 0,U3 ,^ CN CO U-) NO 00 ON 00 On S e o NO NO NO NO NO NO t~* t^ i SIEVE ANALYSES AND TESTS 47 O -"^ O r- -^ ^-H CO 00 00 -^ Tti 00 OO 00 O ^-1 fN 00 »-i r^ ro \o --H '-H O\ooio lovOfN ooo^r- fOt^O ■r-l y-t T-i r^lCNCN .^ ,-, ,-, CNCSCN ooon cnoO'^ 1— i^tir^ TtiOt^ PO ro f) Tf O 00 -^ O 00 es (N !>. tH g; i: ^ ^ o t-- t^ CN CN ^ ON 00 vO ^ CN 00 Os s -* - o o CN ^ OO ''"' t^ 00 00 00 tH t^ I— I o t^ Tt< o vO 00 ^— 1 to O On "* CN o '"' 48 FINE-GRAINED MOLDING SAND Table 13. — Descriptions and Sieve Analyses of Sample num- ber 1 2 SAB LOCATION County Iroquois... Ford Ford Ford Ford... .. . Iroquois. .. Iroquois. .. Iroquois. .. Iroquois. .. Iroquois. .. Kankakee . Kankakee . Kankakee . Cook Cook Winnebago Winnebago Winnebago Winnebago Whiteside . Whiteside . Whiteside . Whiteside . Jo Daviess. Jo Daviess. Jo Daviess. Jo Daviess. Jo Daviess. Jo Daviess. Jo Daviess. Jo Daviess. Carroll.. .. Whiteside . Whiteside . Whiteside . Whiteside . Whiteside . Whiteside . Whiteside . Whiteside . Whiteside . Whiteside . Rock Island . Rock Island . Rock Island . Rock Island . Henry Henry Henry . Mason . Mason . Mason . Mason . Mason . Iroquois . Iroquois. Iroquois. Iroquois. Iroquois. Iroquois. Town near Ridgeville. Piper City. Piper City. Piper City. Piper City. Oilman Woodland . Woodland . Woodland . Pittwood. . St. Anne. . Otto Union Hill Chicago Heights Lansing Pecatonica. Harrison . . Roscoe.. . . Roscoe.. Lyndon . Lyndon . Lyndon . Lyndon . Galena.. Galena.. Galena.. Galena.. Galena. Galena. Galena. Hanover. Savanna. , Morrison. Morrison Fulton . . . Fulton . . . Fulton Union Grove. Lyndon Garden Plain . Garden Plain . Garden Plain . Milan Barstow... . Port Byron. Hillsdale. Colona.. . Atkinson . Hooppole... San Jose — Mason City. Mason City. Mason City. Easton Onarga. Onarga. Onarga . Ridgeville. R idgeville . Woodland . Section NW sw SE SE NE sw sw sw NE SE SE SE SE sw NW NW SW sw NE SE NW SE SE NE NW SE NW NW NE NE NE NW SE NE SE cor. 16 SE cor. 3 SE cor. 2 SE SE NE SW sw SW NW cor. SW NE NW SE SW sw NE NE NE sw NW NW NW NE NE NE SW NW SW cen. cen. cen. NE NE NE NE SW cor. NW SE SE NW cen. NE SE NW NW SE SE SE NE SW NE cor. cor. SW SW SE SE cor. NW SE NE SE cor. SW SE SE NW cen. cen. cen. cen. NW SW SW SW NE NE NE SW NE NE SW NE NE NE NE NW NW NW cor. NW NW NW NW SW NE NE NW SE NW NW SE SE SE SE SE NW 26 N 27 N 27 N 27 N 27 N 26 N 26 N 26 N 26 N 27 N 30 N 30 N 30 N 35 N 36 N 27 N 28 N 46 N 45 N 20 N 20 N 20 N 20 N 27 N 27 N 27 N 27 N 27 N 27 N 27 N 26 N 25 N 21 N 22 N 22 N 22 N 22 N 21 N 20 N 21 N 21 N 21 N 17 N 18 N 19 N 19 N 17 N 17 N 18 N 21 N 21 N 20 N 20 N 20 N 26 N 26 N 26 N 26 N 26 N 26 N 10 E 9 E 9 E 9 E 9 E 14 W 13 W 12 W 12 W 13 W 12 W 14 W 10 E 14 E 15 E 10 E 11 E 2 E 2 E 5 E 5 E 5 E 5 E 1 E 1 E 1 E 1 E 1 E 1 E 1 E 2 E 2 E 4 E 4 E 4 E 4 E 4 E 4 E 5 E 4 E 4 E 3 E 2 W 1 E 2 E 3 E 1 E 4 E 5 E 5 W 5 W 5 W 5 W 7 W 10 E 10 E 10 E 10 E 10 E 12 W ^a Ft. in. 1 6 1 1 5 1 1 2 1 3 1 6 1 6 2 10 2 1 10 1 2 2 4 4 3 4 4 3 6 3 2 10 2 6 1 6 2 3 2 6 3 3 2 6 3 4 8 3 5 8 4 2 4 2 6 3 OVERBURDEN Ft. 3 6 6 1 3 2 1 1 6 1 3 6 1 4 2 4 3 10 Material! 3AB 3AB, 3C. Soil Soil Soil...... 6 and soil . Soil. Soil. Soil. Soil Soil and silt. Soil. Soil. Soil. Soil 26 and soil.. Silt and soil. 25, 26, and soil. Soil and silt Soil Soil 28A and soil 28A,28B, and soil. 31 and soil . Soil Soil and clay Soil Soil and clayey silt. Soil and clayey silt. Soil Soil and clayey silt. 36 and soil Soil and clayey silt. Soil Soil 39A and soil , Soil Soil. Soil. Soil. Soil. Soil. Soil. Soil. Soil. Soil. 52 and soil . Soil Soil 55A and soil 55 A, 55B, and soil. . Soil and clayey sand Soil Soil Underlying material 1 Sandy clay Silty clay 3C 3D Coarser sand More clayey Same — less bond 6A Not exposed Same — less bond Same — less bond Same — less bond Calcareous silt Same — less bond Calcareous sand Not exposed Not exposed Not exposed 25B Calcareous sand 25 Clayey silt 28B 28C Sand and silt Same— less bond Calcareous silt 30 Calcareous sand Medium sand Calcareous silt Not exposed 36B 36B Same Calcareous silt Same — more clayey 39B Clayey silt Calcareous silt Sand— little bond Calcareous silt Calcareous silt Calcareous silt Same — less bond Same — less bond Same — less bond Medium sand Same — less bond Same — calcareous 51 Probably same 55B 55C Coarser sand Not exposed Coarser sand Same — less bond 1 Where the overburden or underlying material has been sampled and a sieve analysis is available, the number of the sample is given. "Same" in the column "Underlying material" means that the material underlying the sample is the same as the sample, the sieve analysis of w^bich is given on the opposite page. DESCRIPTION OF SAMPLES 49 Samples of Molding Sands from Northern Illinois Sample number Remarks SIEVE ANALYSIS, PER CENT RETAINED ON SIEVE 30 40 50 70 100 140 200 270 Pan Clay Total Grain fine- ness number Auger boring; much organic matter. Auger boring; much organic matter. Auger boring; much organic matter. Auger boring; much organic matter. Auger boring; much organic matter, id cut Road cut. Road cut. Road cut. Ditch along road Ditch along road Auger boring W. of R. R. Road cut.. .. Auger boring. Auger boring. Road cut. Road cut. Road cut . Road cut Road cut S. of school Auger boring E. of road cut . Road cut S. of school; part slightly calcareous. Road cut S. of school Road cut Road cut E. of R. R. Auger boring Auger boring Road cut N. of school. Road cut Readout Road cut near house Road cut and auger boring . Road cut Road cut. Road cut. Road cut . Road cut; calcareous. Road cut Road cut Road cut S. of R. R . Road cut and auger boring . Road cut Auger boring. Road cut .... Road cut .... Road cut. Road cut. Road cut. Road cut. Road cut. Road cut. Road cut. Road cut. Road cut . Auger boring. Auger boring. Auger boring. Road cut Auger boring E. of R. R. Road cut 1.0 Tr 1.2 much organic matter. 0.4 0.2 3.0 0.2 0.2 Tr Tr Tr 0.! Tr 0.2 0.4 Tr 2.1 Tr 0.: Tr 0.1 11.2 5. 3. 7. 0. 0.8 4.4 2 2.4 5.8 4.8 9.0 7.6 10.2 8.4 8.2 10.4 12.0 3.6 14.0 16.6 12.4 10.6 5.4 12.4 12.6 1.2 5.4 2 1.4 3.4 0.2 5.0 4.0 2.4 10.0 1.6 4.4 0.4 0.4 0.6 0.2 0.2 0.2 2.0 0.2 2.4 2.6 Tr 4.4 Tr 0.2 Tr 3.6 13 4.6 5 16.8 3 4.0 25.6 8.2 15.4 10.8 12.6 26.0 17.8 28.6 20.4 25.2 32.6 36.0 17.0 38.6 32.4 28.0 33.2 23.0 22.2 19.8 1.4 5 7.4 4.2 15.6 0.2 6.4 17. 13.8 15.4 17.6 8.0 3.2 8.2 1.2 1.2 0.4 0.6 0.2 3 15.2 16 0.4 12.8 0.2 36 22 4 7.0 33.2 16 15 51.6 24.8 26.4 32 5 6.0 12.4 .2 14.2 2 20.2 19.8 19.4 11.4 16.0 10.6 17.4 16.0 32.0 9.0 8.0 0.6 2.0 10 6.0 20.2 0.2 9.2 17.2 13.6 22.6 7.0 7 3.2 8.4 1. 1. 0. 0. 1.0 0. 2. 16.0 17.8 0. 1. 0.4 21.0 18 8.2 6.4 7.6 5.6 9.0 7.0 18.0 18.6 15 7 5.8 16.6 6.0 15.0 5.0 3.2 0.6 1 17.0 14.0 24 0.8 13.6 14.4 14.6 21.2 5.2 11.4 5.2 15.0 1 3.0 2.0 2.2 2.4 1.6 15 15.0 18.4 1 2.0 1.0 1.0 1.2 13.4 10 11. 1 7.0 26.0 34.4 12.4 15.0 8.4 17.8 5.6 4.0 19.0 6.0 8.6 6.4 9.0 5.8 16.0 14.0 43.0 41.0 40.8 50.4 20.2 53.0 31 20.6 30.6 20 30.2 46.0 52.8 11.8 44.2 1.4 54.0 3.2 69.0 15.0 12 9 1.4 3.4 1.4 12.6 15.6 1 2.4 7.2 14.0 11.0 3.0 12 13.6 10.0 15 12 2.8 11 3.4|l0 3.8111.8 29.4 13 23.2 10.0 30.4 21.0 11 8.2 18 2.0 1.8 2.2 1.4 7.4 11.0 7.2 5.2 2.8 3.8 1.6 2.8 3.0 4.0 4.0 1.8 2.0 2.0 8.6 5.2 0.6 2.6 0.2 3.2 3.8 2.6 6.6 71.4 73.6 84.0 56.4 39.6 24.8 30.4 65.0 29 70.0 56 64.6 10.4 5.4 41.6 38.0 7 26.4 26.4 1.8 12.0 5.0 7. 11.2 2. 36.6 28.2 25.2 39.0 21.4 32.6 13.0 5.8 4.2 34.0 9.8 17.4 8.0 16.0 14.0 24.4 29.6 51.2 37 6.0 12.0 2.4 44.4 30.2 15.6 15.0 7.4 18.8 18.4 32.4 2.6 39.6 21 28 23.2 20.0 12.2 26.6 22.2 19.0 8.2 29. 29.2 26.0 34.6 30.4 10 6 36.2 38.0 11.4 14.6 24.0 2 28.4 26 19 30.4 4.8 100.0 100.0 99.6 100.0 100.0 99.6 99.8 100.0 100.0 99.6 99.6 99.2 100.0 100.0 99.6 99 100.0 100 100.0 100.2 100.0 100.0 100.2 100.2 99.8 100.0 100.0 100.0 100.2 99.8 99.8 99.8 100.2 100.8 100.0 99.6 100.0 99.6 99.8 99.8 100.0 99.6 99.6 99.4 99.6 100.0 100 100.0 99.8 100. C 50 FINE-GRAINED MOLDING SAND Table 13- Sample num- ber 58B 59 60 61 62 63 63A 63B 64 65A 65B 65C 65AB 66 67A 67B 68A 68B 69A 69B 70 71 72 73 A 73B 73C 74 75 77A 77B 78A 78B 79 81A 81B 82 83 84A 84B 85 86A 86B 87 88A 88B 89 90 91 92A 92B 92C 93A 93B 94A 94B Iroquois . Iroquois. Iroquois. Iroquois. Cook.,.. Cook.... Cook. Cook. Cook. LOCATION County Whiteside . Whiteside . Whiteside . Whiteside. Whiteside . Whiteside . Whiteside . Whiteside . Whiteside . Whiteside . Whiteside. Whiteside. Whiteside . Whiteside . Whiteside . Whiteside . Whiteside . Whiteside . Whiteside. Jo Daviess lo Daviess Jo Daviess. Jo Daviess. Whiteside . Whiteside. Whiteside. Whiteside. Whiteside . Whiteside . Whiteside . Whiteside. Whiteside. Whiteside. Whiteside . Whiteside. Whiteside. Whiteside. . Whiteside. . Rock Island . Mason . Mason . Mason . Mason . Mason . Mason . Mason . Town near Woodland Pittwood Pittwood Pittwood Chicago Heights Lansing Lansing Lansing Lansing Lyndon Lyndon Lyndon Lyndon Lyndon Lyndon Lyndon Lyndon Lyndon Lyndon Lyndon Fenton Fenton Fenton Round Grove. . Round Grove . . . Round Grove . . . Round Grove.. . Morrison Galena Galena. Galena Galena. Fulton Fulton Fulton Union Grove Union Grove . .. Union Grove Morrison Garden Plain . . Garden Plain . . Garden Plain . . Fulton Fulton Fulton Albany Albany Hillsdale Mason City Mason City Mason City Mason City. . . Mason City Mason City Mason City Mason City Mason City NE SE NE NE SE NW NE NE NE NE NW^ NW Section NE NE SW SW NE SW SE SE SE SE SW NE SE SE cen. cen. NE NW NW SE SE NE NE SE SE NW NW cen. cen. cen. SW SE NW NW SE SE NE NW 20 SW NW 5 NW NE 4 NE NE 33 cor. NE 16 SW cor. 36 SW cor. 36 SW cor. 36 NW SW 36 NE SW 19 NE SW 19 NE SW 19 NE SW SW SW NE SW cor. cor. SW SW SW SE SW NW SE SE SE SE NE SW SW SW NW NW SE SE SE SE SW SE cor. cor. cor. NW NW SW SW NW NE SW 18 NW SE 18 NW SE 18 SE NE 14 NE NW 25 NE NW 25 NE NW 25 SW NW 30 SW SW 16 SW NW 15 SW NW 15 SE SW 9 SE SW 9 SE NE 4 SW SE 30 SW SE 30 NE NE 33 NE NE 33 SE SW 32 SE SW 11 SE SW 29 SE SW 29 NE cor. 31 SW SW 36 SW SW 36 NW NE 19 N 27 N 27 N 28 N 35 N 36 N 36 N 36 N 36 N 20 N 20 N 20 N 20 N 20 N 20 N 20 N 20 N N 20 N 20 N 20 N 20 N 20 N 21 N 21 N 21 N 21 N 21 N 27 N 27 N 27 N 27 N 22 N 22 N 22 N 22 N 22 N 22 N 21 N 21 N 21 N 21 N 22 N 22 N 22 N 21 N 21 N 19 N 21 N 20 N 21 N 21 N 21 N 21 N 21 N 21 N 21 N 12 W 12 W 12 W 12 W 14 E 14 E 14 E 14 E 14 E 5 E 5 E 5 E 5 E 5 E 5 E 5 E 5 E 5 E 4 E 4 E 5 E 5 E 5 t 6 E 5 E 1 E 1 E 1 E 1 E 4 E 4 4 4 E 4 E 4 E 4 E 4 E 4 E 4 E 3 3 4 El 3 3 3 E 5 W 5 W 5 W 5 W 5 W 5 W 5 W 5 W 5 W Ft. in. 2 2 2 2 2 6 3 2 4 8 5 2 6 1 10 6 OVERBURDEN Ft. i 12 Sand, including 58A Soil Soil Soil. Soil. Soil. Soil 63 A and soil . Soil Soil 65A and soil 65A, 65B, and soil Soil. Soil. Soil. 67A and i Soil 68A and soil. Soil 69A and soil Soil Soil. Soil. Soil. Material' 73A and soil 73A.73B, and soil. Soil Soil.. Soil 77.\ and soil Soil 78A and soil Soil Soil.. 80A and soil , Soil 81A and soil Soil Soil.. Soil.. 84A and soil Soil Soil 86 A and soil. Soil Soil ,. 88A and soil . Soil Soil. Soil. Soil. 92 A and soil . . 92A, 92B, and Soil 93A and soil . Soil 94 A and soil . Underlying material* Calcareous sand Same — less bond Same — less bond Not exposed Calcareous clay Slightly calcareous sand 63B Slightly calcareous sand Same 65B 65C Calcareous silt 65C Clay and silt 67B Calcareous medium Not reached 69B Same — calcareous Not exposed Calcareous silt Same — slightly calcar- eous 73B 73C Not exposed Calcareous silt Calcareous sand 77B Pebbly silt 78B Sandy silt Pebbly clay 80B Calcareous silt 81B Calcareous silt Medium sand Clayey silt 84B Silt Calcareous clayey silt Calcareous sandy silt Calcareous sandy silt Calcareous silt Calcareous silt Calcareous silt Medium sand Clayey silt 92B 92C Coarser sand 93B Calcareous silt 94B Not exposed 'Where the overburden or underlying material has been sampled and a sieve analysis is available, the number of the sample is given. "Same" in the column "Underlying material" means that the material underlying the sample is the same as the sample, the sieve analysis of w^hich is given on the opposite page. DESCRIPTION OF SAMPLES 51 Continued Sample number Remarks SIEVE ANALYSIS, PER CENT RETAINED ON SIEVE 30 40 50 70 100 140 200 270 Pan Clay Total Grain fine- ness number Road cut. Road cut. Road cut. Road cut. Auger boring Ditch along road . Ditch along road . Ditch along road . Road cut Auger boring S. of road cut. Auger boring S. of road cut. Auger boring S. of road cut. Auger boring S. of road cut. Auger boring N. of R. R. . . . Auger boring Auger boring. Auger boring. Auger boring Road cut. Road cut. Road cut . Road cut ... Auger boring. Road cut. Road cut Road cut: calcareous. Road cut Stream cut S. of road . . Auger boring SW. of hill . Auger boring SW. of hill . Auger boring W. of R. R. Auger boring W. of R. R. Road cut Road cut. Road cut. Road cut. Road cut. Road cut . Road cut. Road cut E. of R. R. Road cut E. of R. R. Road cut Road cut Road cut and auger boring . Road cut Road cut. Road cut. Road cut. Road cut Road cut Road cut; much organic matter. Road cut. Road cut. Road cut. Tr Tr Tr Tr Tr Road cut. Road cut. Road cut. 2.4 2.4 3.0 2.4 1.6 0.4 0.6 0.6 2.0 Tr Tr 0.2 Tr 0.2 Tr Tr Tr 5.0 14 5.2 27.4 Tr 0.4 2.2 1.4 12 2.2 5.0 0.6 0.2 0.2 0.6 Tr 0.2 Tr 0.2 7 2.6 8.8 30.0 Tr 4. J 2.0 11.2 1.8 5.2 0.2 0.4 7.2 2.0 0.2 0.2 0.2 0.2 0.8 4.8 Tr 3.0 3.2 Tr 1.4 0.2 0.4 Tr 0.4 Tr 3.0 8.8 6.4 4.4 12.8 5.4 2.8 16.8 18.4 31.4 31.4 31.6 31.4 3.6 23.0 21.8 24.4 35.4 9.6 4.2 1.4 7.4 0.4 3.8 0.8 23.0 7.0 23.8 20.2 0.2 25.6 21.2 6.4 19.8 3.2 8.6 0.4 1.2 24.2 12.2 0.4 0.2 0.4 1.0 4.0 9.2 0.6 21.8 20.2 0.4 3.2 0.4 2.2 0.2 2.2 0.2 24.8 18.4 34.8 15.0 8.0 38.4 40.4 22.8 24.8 24.2 24.0 2.8 54.4 53.4 57.0 46.8 18.4 10.8 1.8 15.0 0.2 10.2 1.2 19.6 5.0 16.8 4.4 0.2 21.6 6.2 8.6 1.6 3.6 0.6 1.6 19.0 16.6 0.2 0.4 0.6 1.4 3.8 4.2 0.4 18.4 22.0 0.2 1.8 0.8 2.6 0.4 2.4 0.2 7.0 11 8 9.4 5.2 19.4 9.0 16.2 15.4 21.0 16.4 18.0 15.6 2.6 11.2 12.4 11.0 6.0 20.8 17.6 2.4 19.4 0.8 16.0 4.0 16.8 3.6 12.6 2.4 0.6 16.8 7.4 10.0 7.4 2.6 3.6 1.4 3.6 13.4 17.2 0.8 1.4 1.4 3.4 6.6 4.0 1.0 16.4 18.8 1.0 2.2 1.8 5.2 1.0 4.0 0.4 9.4 7.0 5.6 3.0 12 4 5.8 3.2 8.8 8.0 3.0 5.4 4.6 4.0 14.0 3.2 2 1.6 1.2 33.4 38.6 58.8 30.4 55.8 39.8 54.8 52.4 14.8 44.0 17.8 2.4 54.4 17.4 30.2 48.2 31.6 60.8 50.0 62.0 63.0 20.2 31.6 60.2 69.0 69.2 59.4 59.6 47.8 56.4 21.6 26.2 53.0 56.8 66.6 68.6 62.8 63.8 52.4 29.8 16.2 19.2 25.6 4.8 29.6 40.8 5.6 4.2 71 4 5.0 6.6 2.2 2.4 15.0 19.0 34.2 17 41.2 21.0 38.2 37.2 3.4 35.8 9.4 43.8 8.6 16.2 20.0 7.6 26.0 23.4 34.2 27.0 10.8 14.8 37.6 26.8 26.6 30.4 18.8 24.4 39.4 11.6 5.4 45.0 32.2 28.4 15.8 34.8 23.4 34.8 28.4 37.2 50.2 6.2 31.8 38.4 7.2 4.6 99.6 99.8 99.4 100.4 100.0 100.2 100.0 100.0 99.6 100.0 100.2 100.2 100.2 99.8 100.2 100.0 100.0 99.8 100.2 100.0 99.6 100.0 100.2 99.8 99.8 100.0 100.0 99.6 100.0 100.0 99.8 100.0 100.2 100.0 100.2 100.0 99.8 99.8 100.0 100 100.0 100.0 100.2 100.0 99.8 100 100.0 99.8 100.2 100.0 52 FINE-GRAINED MOLDING SAND Table 13- LOCATION Ft. in. OVERBURDEN Sample num- ber County Town near Section K M M 1 eg e5 Ft. in. Materiali Underlying material! 95A Mason Mason Mason City Mason City Mason City Mason City Mason City Teheran NE SE NE 12 NE SE NE 12 NE SE NE 12 SE SW, SE 2 SE SW SE 2 NE SW SE 33 NE SW SE 33 NW NW NE 2 NE NE SE 29 SE SW NW 29 SW cor. 12 NW NE SE 24 NW NE SE 24 SW SW SW 26 SW SW SW 12 SW SW SW 35 NE SE SW 16 NW NE SW 14 NW SW NW 18 SE SW NE 31 20 N 20 N 20 N 20 N 20 N 21 N 21 N 35 N 33 N 33 N 33 N 33 N 33 N 33 N 36 N 36 N 34 N 17 N 36 N 36 N 6 W 6 W 6 W 6 W 6 W 6 W 6 W 14 E 8 E 8 E 8 E 8 E 8 E 9 E 10 E 14 E 8 E 3 E 15 E 15 E 2 6 3 2 3 3 2 1 6 4 4 3 5 1 6 2 2 2 1 3 2 4 9 5 6 6 3 6 1 4 3 6 6 1 6 6 2 6 6 2 6 I Soil 95B 95B 95A and soil 95A, 95B, and soil. . Soil 96A and soil Soil 95C 95C Slightly calcareous sand 96B Calcareous sand 97B 96A 96B 97A Mason Mason Mason 97B 98 Mason Cook Teheran 97A and soil Soil Slightly coarser sand Slightly calcareous sand Pebbly sand 99 Grundy Grundy Grundy Grundy Grundy Will Will Coal City Soil 100 Coal City Coal City Coal City Soil Shale 101 Soil .... Calcareous clavey silt 102 Soil 102 and soil Soil 103 103 104 Coal City Wilmington Lockport Thornton Calcareous medium sand 105 Soil and clay Soil Calcareous sand 106 Cook Grundy Rock Island .... Cook Not exposed 107 Soil Soil 108 109 Sears Calumet City Lansing Calcareous sandy silt Not exposed Not exposed 110 Cook ^Where the overburden or underlying material has been sampled and a sieve analysis is available, the number of the sample is given. "Same" in the column "Underlying material" means that the material underlying the sample is the same as the sample, the sieve analysis of which is given on the opposite page. DESCRIFTIOX OF SAMPLES 53 Concluded Sample number Remarks SIEVE ANALYSIS. PER CENT RETAINED ON SIEVE 30 40 50 70 100 140 200 270 Pan Clay Total Grain fine- number 95A 95B 9.5C 96A 96B 97A 97B 100 101 102 103 104 105 106 107 109 110 Road cut Road cut Road cut and auger boring Road cut. Road cut . Road cut. Road cut Ditch along road . Claypool ditch . . . Strip-mine cut Auger boring. . Strip-mine cut . Strip-mine cut cut cut N. of creek; small deposit. Ditch at road T Auger boring Molding sand pit; calcareous. Small pit. Small pit. Tr 1.2 1.2 1.2 2.8 3.0 0.4 15.2 17.4 2.2 11.8 10.4 Tr 7.C 12.6 9.4 10.0 14.6 1.0 16.2 22.4 0.6 19.6 23.4 18.4 1.0 9 4 11.6 Tr 3.3 31.6 38.6 49.8 53. C 19.8 21.6 18.4 5.6 41.8 12.4 14.4 6.2 5.8 16.2 2 2 1.8 2.4 5.0 2.6 4.8 18.2 12.0 4.2 0.6 1.6 1.5 22.2 35.6 17.8 20 4.6 3.2 31.2 2.4 1.0 3.2 5.0 3.4 78.4 0.4 0.5 12.2 4.0 2.6 23.8 12 22.2 25.0 29.8 7.4 59.4 7.0 3.0 6.0 14.0 7.2 12.0 15.6 0.5 1.0 100 2 99.8 100.0 100.0 100.0 99.6 99.8 99.6 100.0 99.8 99.8 99.6 100.0 100.0 99.6 99.8 100.0 100.0 106 00 163 189 133 141 113 104 76 255 77 79 135 98 91 291 78 67