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)
“And in their blazing solitude
The stars sang in their sockets through the night:
“Blow bright, blow bright
The coal of this unquickened world.””
—Philip Larkin (1922–1986)
“This island is made mainly of coal and surrounded by fish. Only an organizing genius could produce a shortage of coal and fish at the same time.”
—Aneurin Bevan (1897–1960)