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:
“Mr. Christian, it is about time for many people to begin to come to the White House to discuss different phases of the coal strike. When anybody comes, if his special problem concerns the state, refer him to the governor of Pennsylvania. If his problem has a national phase, refer him to the United States Coal Commission. In no event bring him to me.”
—Calvin Coolidge (1872–1933)
““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)