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pyrite

(Encyclopedia)pyrite pīrīˈtēz, pə–, pīˈrīts [key], pale brass-yellow mineral, the bisulfide of iron, FeS2. It occurs most commonly in crystals (belonging to the isometric system and usually in the form of...

Bessemer process

(Encyclopedia)CE5 Bessemer converter Bessemer process bĕsˈəmər [key] [for Sir Henry Bessemer], industrial process for the manufacture of steel from molten pig iron. The principle involved is that of oxidati...

thermite

(Encyclopedia)thermite [from Thermit, a trade name], mixture of powdered or granular aluminum metal and powdered iron oxide. When ignited it gives off large amounts of heat. In wartime it has been used in incendiar...

Youngstown

(Encyclopedia)Youngstown, city (1990 pop. 95,732), seat of Mahoning co., NE Ohio, near the Pa. line; founded 1797, inc. 1849. It was formerly a major U.S. iron and steel center. In the 1970s many of the steel mills...

ferric

(Encyclopedia)ferric fĕrˈĭk [key], iron in the +3 valence state. ...

ferrous

(Encyclopedia)ferrous fĕrˈəs [key], iron in the +2 valence state. ...

carbide

(Encyclopedia)carbide, any one of a group of compounds that contain carbon and one other element that is either a metal, boron, or silicon. Generally, a carbide is prepared by heating a metal, metal oxide, or metal...

Wood, Jethro

(Encyclopedia)Wood, Jethro, 1774–1834, American inventor, b. either in Dartmouth, Mass., or in Washington co., N.Y. In 1814, while a farmer in Cayuga co., N.Y., he patented a cast-iron plow in which he later embo...

pentlandite

(Encyclopedia)pentlandite pĕntˈləndīt [key], yellowish-bronze, opaque mineral, a sulfide of iron and nickel, (Fe,Ni)9S8. It is found in masses nearly always associated with the iron sulfide pyrrhotite. The larg...

density

(Encyclopedia)density, ratio of the mass of a substance to its volume, expressed, for example, in units of grams per cubic centimeter or pounds per cubic foot. The density of a pure substance varies little from sam...