Shale - WikipediaBefore the mid 19th century, the terms slate, shale and schist . In the context of underground coal mining, shale was.shale in coal mining,Oil Shale - Nevada Bureau of Mines and Geology - University of .Oil shale was first recognized in Nevada in the Elko area in 1875 and has since . and in Coal Mine Canyon. of these three areas, the richest oil-shale deposits.
shale in coal mining