Coal

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:

    “The room’s very hot, with all this crowd,” the Professor said to Sylvie. “I wonder why they don’t put some lumps of ice in the grate? You fill it with lumps of coal in the winter, you know, and you sit round it and enjoy the warmth. How jolly it would be to fill it now with lumps of ice, and sit round it and enjoy the coolth!”
    Lewis Carroll [Charles Lutwidge Dodgson] (1832–1898)

    ... 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)