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You searched for: Corporate Names Hanna Coal Company. Remove constraint Corporate Names: Hanna Coal Company. Topical Subjects Coal-mining machinery--Ohio--Georgetown. Remove constraint Topical Subjects: Coal-mining machinery--Ohio--Georgetown.
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Caption on back reads, 'Stiff-arming a highwall is the job of this new, double-decker drill in operation at the Georgetown mine, Hanna Coal Co., at Georgetown, Ohio. Fruit of the ingenuity of coal mining engineers, the drill makes two blast holes at different levels in the highwall, permitting a blasting shot that brings down a large section of 'overburden.' The 'overburden,' rock, shale, limestone, clay and other mineral deposits, lies above the coal seam. Surface, or open-pit mining, accounts for 23 percent of total bituminous production. The Georgetown mine is the largest surface mine in the world.'