Coal mining is the process of extracting coal from the ground. Coal is valued for its energy content, and, since the 1880s, has been widely used to generate electricity. Steel and cement industries use coal as a fuel for extraction of iron from iron ore and for cement production.
A. Abutment - In coal mining, (1) the weight of the rocks above a narrow roadway is transferred to the solid coal along the sides, which act as abutments of the arch of strata spanning the roadway; and (2) the weight of the rocks over a longwall face is transferred to the front abutment, that is, the solid coal ahead of the face and the back abutment, that is, the settled packs behind the face.
A mine railway (or mine railroad, U.S.), sometimes pit railway, is a railway constructed to carry materials and workers in and out of a mine. Materials transported typically include ore, coal and overburden (also called variously spoils, waste, slack, culm, and tilings; all meaning waste rock).