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Copper
Copper river, c.300 mi (480 km) long, rising in the Wrangell Mts., SE Alaska, and flowing S through the Chugach Mts. to the Gulf of Alaska. Copper deposits near the upper river, long mined by natives, attracted the attention of Russians and later Americans, but exploration was difficult because of ...
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Val d'Or
Val d'Or , town (1991 pop. 23,842), SW Que., Canada, SE of Rouyn-Noranda. It is a mining center. Gold was discovered in the region in 1909; copper, zinc, lead, and molybdenum are also mined.
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Sudbury
Sudbury city (1991 pop. 92,884), central Ont., Canada. It is the center of Canada's largest mining region, which produces much of the world's nickel and large quantities of copper, platinum, gold, silver, cobalt, and sulfur. Laurentian Univ. (1960) is there.
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German silver
German silver name for various alloys of copper, zinc, and nickel, sometimes also containing lead and tin. They were originally named for their silver-white color, but use of the term silver is now prohibited for alloys not containing that metal. German silver varies in composition, the percentag...
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Douglas
Douglas 1 City (1990 pop. 12,822), Cochise co., SE Ariz., at the Mexican border; inc. 1905. The mining and smelting of copper have been important since 1900; the city grew around a copper smelter, now abandoned and largely dismantled. Douglas is also a ranching center and a border station, with p...
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ormolu
ormolu , finish used on metal to imitate gold. It is employed chiefly for furniture mountings. The term originally applied to a coating of ground gold and was extended to alloys of copper and zinc. Ormolu mountings were characteristic of 18th-century furniture and attained their highest artistic and...
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Zambia
Zambia , officially Republic of Zambia, republic (2005 est. pop. 11,262,000), 290,584 sq mi (752,614 sq km), central Africa. It borders on Congo (Kinshasa) in the north, on Tanzania in the northeast, on Malawi and Mozambique in the east, on Zimbabwe, Botswana, and Namibia in the south, and on Angola...
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nickel
nickel metallic chemical element; symbol Ni; at. no. 28; at. wt. 58.69; m.p. about 1,453°C; b.p. about 2,732°C; sp. gr. 8.902 at 25°C; valence 0, +1, +2, +3, or +4.
Nickel is a hard, malleable, ductile, lustrous, silver-white metal with a face-centered cubic crystalline structure. ...
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silver
silver metallic chemical element; symbol Ag [Lat. argentum ]; at. no. 47; at. wt. 107.8682; m.p. 961.93°C; b.p. 2,212°C; sp. gr. 10.5 at 20°C; valence +1 or +2. Pure silver is nearly white, lustrous, soft, very ductile, malleable, and an excellent conductor of heat and electricity. In ...
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fiber optics
fiber optics transmission of digitized messages or information by light pulses along hair-thin glass fibers. Each fiber is surrounded by a cladding having a high index of refractance so that the light is internally reflected and travels the length of the fiber without escaping. Cables of optical fi...
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