Coal
Coal (from the Old English term col, which has meant "mineral of fossilized carbon" since the 13th century) is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure. Coal is composed primarily of carbon along with variable quantities of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen.
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Famous quotes containing the word coal:
“Coal lay in ledges under the ground since the Flood, until a laborer with pick and windlass brings it to the surface. We may will call it black diamonds. Every basket is power and civilization. For coal is a portable climate.”
—Ralph Waldo Emerson (1803–1882)
“... gathering news in Russia was like mining coal with a hatpin.”
—Mary Heaton Vorse (1874–1966)
“In those days, the blag slag, the waste of the coal pits, had only begun to cover the side of our hill. Not enough to mar the countryside nor blacken the beauty of our village. For the colliery had only begun to poke its skinny black fingers between the green.”
—Philip Dunne (1908–1992)