Preliminary microscopic investigation of Illinois coal

Petrographic techniques and the microscopic maceral and mineral components of coal were reported in this study of Illinois coal. Sample preparation was accomplished utilizing a modification of Thiessen's technique. Pyrite, quartz, and calcite were the major inorganic constituents identified in the petrographic studies. The microscopic appearance of mineral and plant remains in the coal were described in the report. The author speculated about the geologic origin of individual maceral and mineral components in coal.