Almost 600 insoluble-residue and quantitative X-ray analyses have been performed on samples collected from the Callville and Pakoon Formations (Pennsylvanian and Lower Permian) of southern Nevada. The gross lithologies present are limestone, dolostone, and carbonate-cemented sandstone. The insoluble residues range from 0.7 to 77.0% and consist of fine-sand size quartz with varying amounts of illite (clay).

Plots of the total insoluble residue against percent dolomite show that more than 500 of the samples fall into either limestone (greater than 90% calcite) or dolostone (greater than 90% dolomite) end members. Plots of the dolomite percentage in the 100 remaining, mixed-calcite-dolomite mineralogy specimens versus total insoluble residue showed no obvious trends. Plots of the mixed-mineralogy specimens versus the illitic clay content likewise showed no obvious trends.

Five limestone facies (micrite, sparse micrite, packed micrite, biopelsparite and oosparite) were recognized. No relation was found between limestone facies and percent total insoluble residue or between percent dolomite and limestone facies.

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