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 is a portable climate. It carries the heat of the tropics to Labrador and the polar circle; and it is the means of transporting itself whithersoever it is wanted. Watt and Stephenson whispered in the ear of mankind their secret, that a half-ounce of coal will draw two tons a mile, and coal carries coal, by rail and by boat, to make Canada as warm as Calcutta, and with its comfort brings its industrial power.”
—Ralph Waldo Emerson (1803–1882)
“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)
“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)