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tin

(Encyclopedia)tin, metallic chemical element; symbol Sn [Lat. stannum]; at. no. 50; at. wt. 118.710; m.p. 231.9681℃; b.p. 2,270℃; sp. gr. 5.75 (gray), 7.3 (white); valence +2 or +4. Tin exhibits allotropy; abov...

limonite

(Encyclopedia)limonite hĕmˈətīt, hēˈ– [key], yellowish to dark brown mineral, a hydrated oxide of iron, FeO(OH)·nH2O, occurring commonly in deposits of secondary origin, i.e., those formed by the alteratio...

Mesabi

(Encyclopedia)Mesabi məsäbˈē [key], range of low hills, NE Minn., once famous for its extensive iron ore deposits. The ores were found in a belt c.110 mi (180 km) long and from 1 to 3 mi (1.6–4.8 km) wide bet...

Cort, Henry

(Encyclopedia)Cort, Henry, 1740–1800, English inventor. He revolutionized the British iron industry with his use of grooved rollers to finish iron, replacing the process of hammering, and through his invention of...

copper, chemical element

(Encyclopedia)copper, metallic chemical element; symbol Cu [Lat. cuprum=copper]; at. no. 29; at. wt. 63.546; m.p. 1,083.4℃; b.p. 2,567℃; sp. gr. 8.96 at 20℃; valence +1 or +2. Copper and some of its alloys ha...

blast furnace

(Encyclopedia)CE5 Blast furnace for production of iron blast furnace, structure used chiefly in smelting. The principle involved in this means of extracting metals is that of the reduction of the ores by the ac...

Chou

(Encyclopedia)Chou jō [key], dynasty of China, which ruled from c.1027 b.c. to 256 b.c. The pastoral Chou people migrated from the Wei valley NW of the Huang He c.1027 b.c. and overthrew the Shang dynasty. The Cho...

mixture

(Encyclopedia)mixture, in chemistry, a physical combination of two or more pure substances (i.e., elements or compounds). A mixture is distinguished from a compound, which is formed by the chemical combination of t...

Erzberg

(Encyclopedia)Erzberg ĕrtsˈbĕrkh [key], peak, 3,531 ft (1,076 m) high, in Styria, central Austria. Rising above the town of Eisenerz, the Erzberg is almost literally a mountain of iron. Its rich iron ore (about ...

stellar evolution

(Encyclopedia)CE5 The above Hertzsprung-Russell (H-R) diagram shows the track of stellar evolution for a typical star. After spending much of its life evolving toward or along the main sequence, the star becomes...