1902 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. Anonymous, "Arkansas Anthracite Coal."-Bulletin of Engineering and Mining Journal, Vol. 73, p. 277; 1902. Obtainable from McGraw-Hill Book Company, 10th Avenue at 36th Street, New York. 1903 Bache, Franklin, "The Arkansas-Indian Territory Coal Field."-Bulletin of the Engineering and Mining Journal, Vol. 76, pp. 390-392; 1903. Obtainable from McGraw-Hill Book Company, 10th Avenue and 36th Street, New York. 1905 Crane, Walter R., "Coal Mining in Arkansas."-Bulletin of the Engineering and Mining Journal, No. 80, pp. 774-777; 1905. Obtainable from McGraw-Hill Book Company, 10th Avenue at 36th Street, New York. 1906 Campbell, Marius Robison, "The Classification of Coals."-American Institute of Mining Engineers, Bi-Mo. Bulletin No. 5, pp. 1033-1049, 1905; Tr. 36, pp. 324-340, 1906. Obtainable from McGraw-Hill Book Company, 10th Avenue at 36th Street, New York. 1907 Collier, Arthur J., "The Arkansas Coal Field."-Bulletin of the U. S. Geological Survey, No. 326, pp. 137-160. Now out of print, but may be consulted in public libraries. Girty, Geo. Herbert, "Report on the Marine Carboniferous Fossils from the Coal Fields of Arkansas."-Bulletin of the U. S. Geological Survey, No. 326, pp. 31-35; 1907. Now out of print, but may be consulted in public libraries. White, Chas. David, "Report on Fossil Plants from the Coal Measures of Arkansas."-Bulletin of the U. S. Geological Survey, No. 326, pp. 2431; 1907. Out of print, but may be consulted in public libraries. 1910 Douglas, James, "Coal Mining in Arkansas."-Bulletin of the Engineering and Mining Journal, January 15, 1910, p. 166. Obtainable from McGraw-Hill Book Company, 10th Avenue at 36th Street, New York. Steele, Alvin Arthur, "Coal Mining in Arkansas.”—Annual Report of the Arkansas Geological Survey, Parts I and II, 1910. Obtainable from Office of State Geologist, 447 Capitol Bldg., Little Rock, Ark. 1914 Hackett, Edward F., "The Coal Fields of Sebastian County."-Bulletin of Arkansas Coal Age, No. 6, pp. 630-631; 1914. Obtainable from McGraw-Hill Book Company, 10th Avenue at 36th Street, New York. 1916 Stevenson, John J., "Coal Formations."-(Abstract of Paper before American Philosophical Society), 1916; Science, N. S. No. 43, p. 722. Obtainable from Science Press, Grand Central Terminal, New York. The lignite beds of the Coastal Plain of Arkansas are part of the Gulf coal province of the United States and are directly related to the lignite of northern Texas, Mississippi, and Alabama. The lignites are found in the Eocene series of beds both in the eastern and southern part of the Arkansas Coastal Plain, but more particulary in the south. These beds are comparatively undisturbed. The lignite beds are usually found with an overburden of soft clays and sands of varying thicknesses depending on the amount of surface erosion. Deep well drillers have frequently reported the penetration of lignite beds in various parts of the Coastal Plain. A lignite bed of twelve feet in thickness was reported as penetrated at a depth of 1,064 feet in a deep well near Altheimer, Jefferson county. Outcropping lignite beds have been found in northern Ouachita, northern Calhoun, southern Dallas, southern Bradley, and in Poinsett and Clay counties. The most valuable field now known is the Ouachita county field, which lies northwest of Camden. This field probably covers an area of sixty square miles and usually varies in thickness from two to three Number and one-half feet with extreme thicknesses of six feet. The deposit is estimated to contain 75,000,000 tons.* Lignite from the Ouachita county field is high in bituminous matter, distillation tests showing that it contains an average of about twenty-five gallons of oil to the ton. The gas-producing qualities as determined by the Pittsburgh Testing Laboratory indicate that this lignite ranks with the best cannel coal as a gas producer and also in the candlepower of the gas which was determined as 22.3. On account of the high water content (from 30 to 40 per cent) the coal cannot be used directly for burning unless provided with suitable grates. When air-dried it offers possibilities as a commercial fuel, and may be used directly and in powdered form and also for briquette manufacture. Some local use has been made of the lignite, and the distillation of the oils has been carried on in a small way. A bed of lignite exposed on the Saline River near Broad, south Bradley county, has a thickness of two feet. Lignite beds on Crowley's Ridge in Green and Clay counties have a thickness of one and one-half feet. The Arkansas lignite is typical of the lignite or brown coal class as the ratio of the fixed carbon to the volatile combustible matter is less than 1 and the water content is greater than 10 per cent. The conchoidal fracture of the coal, its woody structure and its disintegration in the air are also characteristic of lignites or brown coals. Some Analyses of Ouachita County Lignites The following are analyses of Ouachita county lignites according to the U. S. Geological Survey figures: Variety of Coal Locality Water in Fresh Coal V. C. M.1 +22 38.72 36.90 16.90 7.50 .50 † 1 Brown coal, or lignite Brown Mine, Ouachita Co....... 3 326. 1V. C. M.-Volatile combustible matter. 2B. T. U.-British thermal units. 6360 Twenty-first Annual Report of the U. S. Geological Survey, Part IIf, of 1900, page According to Bulletin 255, issued by the U. S. Bureau of Mines on "Investigations of the Preparation and Use of Lignite," the fol *Preliminary Report on the Camden Coal Field of Southwestern Arkansas, by J. A. Taff, Twenty-first Annual Report, U. S. Geological Survey, Part II f. lowing yields result from the carbonization of a good grade of North Dakota lignite in the Bureau of Mines carbonizer: One ton of lignite (2,000 pounds) 800 pounds of char. 16,000 cubic feet of producer gas having a calorific value of 110 B. T. U. per cubic foot. 15 pounds of ammonium sulphate. 30 pounds of tar per ton, yielding upon distillation the following: 67% pitch, 3% loss. The use of lignite directly as a fuel is increasing, although, on account of its high percentage of water (from 30 to 40 per cent) it requires a special grate. It has in the raw form about one-half of the calorific value of good bituminous coal. Bibliography of Arkansas Lignite Morris, Henry C., Riddle, J. L., and Glover, James.-Papers relating to the coal fields of the upper Ouachita River submitted to the Academy of Sciences of New Orleans. Published by the New Orleans Picayune, 1857, and probably obtainable there. 1873 Britton, Blodgett J., "The Lignite of Arkansas."-Bulletin of the American Institute of Mining Engineers, Tr. 1, pp. 223-224; 1873. Obtainable from McGraw-Hill Book Company, 10th Avenue at 36th Street, New York. 1902 Taff, Joseph A., "The Southwestern Coal Field."-Twenty-second Annual Report of the U. S. Geological Survey, Part II, pp. 367-413; 1902. Out of print, but may be consulted in public libraries. 1915 Babcock, E. J., "Economic Methods of Utilizing Western Lignites."Bureau of Mines, Bulletin 89, 1915. Out of print, but may be consulted in public libraries. 1926 Hood, O. P., and Odell, W. W., "Investigations of the Preparation and Use of Lignite."-Bureau of Mines Bulletin No. 55. Obtainable from Superintendent of Documents, Washington, D. C., for 50c. COPPER The only economic source of copper as yet discovered in Arkansas is the mineral chalcopyrite, or copper pyrites, which is intimately associated with galena in nearly all of the known occurrences of that mineral. There is, so far as is known, no great quantity of copper in Arkansas, although there are many places where traces of it occur in the rocks. Incrustations of azurite, the blue copper carbonate, are common in the black shales, but these are of no commercial importance. In some instances, vein deposits of native copper have been found. Native copper occurs impregnating a quartz vein near Olsen switch west of Benton. An opening has been made in this vein for the purpose of mining the copper, but because of the irregular distribution of the metal in the vein, and the large amount of gangue that must be handled in recovering the metal, it is probable that this vein cannot be worked profitably at the present time. A little metallic copper was found at the Rossin shaft, four miles east of Harrison, but not in commercial quantities. A small amount of malachite (hydrous copper carbonate) was mined at the "Tomahawk Mine" in Section 6, Township 16 north, Range 16 west, in Searcy County. Two assays of malachite from this locality gave 39.48 and 39.57 per cent of metallic copper. Small quantities of the same material were shipped from the Big Bear mine near Ferndale, Pulaski County, but the mining of these ores did not prove profitable. Where copper minerals occur in connection with lead, zinc or other metallic ores, it is often possible to profitably save the copper as a by-product. So far as is now known there are no copper deposits in Arkansas that warrant working for copper alone. The location of the Tomahawk mine is shown on the map of the zinc and lead district. It lies in a district in which zinc mineralization is common. 1. 2. Bibliography of Copper 1888 Comstock, T. B., "Gold and Silver."-Annual Report of the Arkansas Geological Survey for 1888, Vol. I. 1892 Branner, J. C., "Zinc and Lead Region of North Arkansas."-Annual Report of the Arkansas Geological Survey for 1892, Vol. V. |