This geological study of the siliceous materials found in southern Illinois provides a comprehensive analysis of the region's unique geological formations. The author, a noted petrologist, provides detailed descriptions of the various types of silica-bearing rocks found in the region, as well as their mineral composition and uses. The book also includes detailed maps and charts, as well as photographic illustrations of the various rock formations. This book is essential reading for anyone interested in the geology of the Midwestern United States.

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