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cyanide process

(Encyclopedia)cyanide process or cyanidation, method for extracting gold from its ore. The ore is first finely ground and may be concentrated by flotation; if it contains certain impurities, it may be roasted. It i...

bromide

(Encyclopedia)bromide, any of a group of compounds that contain bromine and a more electropositive element or radical. Bromides are formed by the reaction of bromine or a bromide with another substance; they are wi...

Daly, Marcus

(Encyclopedia)Daly, Marcus, 1841–1900, American copper magnate, b. Ireland. He went to New York City at 15 and later moved to California, where he worked as a miner. He was employed by the “silver kings,” J. ...

amalgamation process

(Encyclopedia)amalgamation process əmălˌgəmāˈshən [key], in particular, a method to extract gold and silver from ores. The ore is crushed and treated with mercury, in which the metal dissolves. The amalgam i...

Oruro

(Encyclopedia)Oruro ōro͞oˈrō [key], city (1992 pop. 183,422), capital of Oruro dept., W Bolivia. It is Bolivia's railroad center. Oruro's economy is based on exploitation of the region's tin, tungsten, and copp...

bismuth

(Encyclopedia)bismuth bĭzˈməth [key] [Ger. Weisse Masse=white mass], metallic chemical element; symbol Bi; at. no. 83; at. wt. 208.98040; m.p. 271.3℃; b.p. about 1,560℃; sp. gr. 9.75 at 20℃; valence +3 or ...

Moser-Pröll, Annemarie

(Encyclopedia)Moser-Pröll, Annemarie, 1953–, Austrian skier. One of the world's greatest Alpine skiers, Moser-Pröll dominated women's skiing in the 1970s, and her 62 World Cup wins from 1970 through 1980 set th...

amalgam

(Encyclopedia)amalgam əmălˈgəm [key], alloy containing mercury. The alloy may be liquid or solid, depending on the proportion of mercury, although all naturally occurring amalgams, i.e., those of gold and silve...

Fair, James Graham

(Encyclopedia)Fair, James Graham, 1831–94, American financier, b. near Belfast, Ireland. He emigrated to America as a child, grew up on an Illinois farm, and went west in 1851 in search of gold. In partnership wi...

Park City

(Encyclopedia)Park City, town (1990 pop. 4,468), Summit co., N central Utah, in the Wasatch Range. A former mining town whose silver and other deposits were mined out, it was a nearly ghost town by the 1950s but ha...