History of anthracite coal mining in Pennsylvania History of anthracite coal mining in Pennsylvania There are two types of coal found in Pennsylvania: anthracite (the “hard coal” found in Northeastern Pennsylvania below the Allegheny Ridge southwest to Harrisburg; also called “stone coal”, “rock coal” in the 1800s) and bituminous (“soft coal”, found west of the Allegheny Front escarpment). Anthracite coal is a natural mineral with a high carbon and energy content that gives off light and heat (produced energy) when burned, making it useful as a fuel. It was possibly first used in Pennsylvania as a fuel in 1769, but its real history begins with a documented
Coal assay non-combustible residue left after coal is burnt. It represents the bulk mineral matter after carbon, oxygen, sulfur and water (including from clays) has been driven off during combustion. Analysis is fairly straightforward, with the coal thoroughly burnt and the ash material expressed as a percentage of the original weight. It can also give an indication about the quality of coal. Ash content may be determined as air dried basis and on oven dried basis. The main difference between the two is that the latter is determined after expelling the moisture content in the sample of coal The fixed carbon content