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:
“Writing is to descend like a miner to the depths of the mine with a lamp on your forehead, a light whose dubious brightness falsifies everything, whose wick is in permanent danger of explosion, whose blinking illumination in the coal dust exhausts and corrodes your eyes.”
—Blaise Cendrars (1887–1961)
“... gathering news in Russia was like mining coal with a hatpin.”
—Mary Heaton Vorse (1874–1966)
“The discovery of Pennsylvania’s coal and iron was the deathblow to Allaire. The works were moved to Pennsylvania so hurriedly that for years pianos and the larger pieces of furniture stood in the deserted houses.”
—For the State of New Jersey, U.S. public relief program (1935-1943)