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amalgam
amalgam , 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 silver, are solid. Amalgams are widely used. Silver, gold, and copper amalgams are used in dentistry, and tin amalgam i...
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amalgamation process
amalgamation process , 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 is heated and the mercury evaporates, leaving pure gold or silver. The process has been criticized as an environmental and occ...
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free silver
free silver in U.S. history, term designating the political movement for the unlimited coinage of silver.
Origins of the Movement
Free silver became a popular issue soon after the Panic of 1873, and it was a major issue in the next quarter century. The hard times of 1873-78 stimulated adv...
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gold
gold metallic chemical element; symbol Au [Lat. aurum =shining dawn]; at. no. 79; at. wt. 196.9665; m.p. 1,064.43°C; b.p. 2,808°C; sp. gr. 19.32 at 20°C; valence +1 or +3.
Gold is very ductile and is the most malleable metal; it can be beaten into extremely thin sheets of gold lea...
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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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Carl Lewis
Carl Lewis (Frederick Carlton Lewis), 1961-, American sprinter and jumper, b. Birmingham, Ala. A star in high school and at the Univ. of Houston, he became possibly the greatest track athlete of all time. After winning three gold medals at the World Championships in Helsinki in 1983, he went on at ...
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Copperbelt
Copperbelt mining region, N central Zambia, central Africa. A natural extension of the mineral-rich region of Katanga , the Copperbelt is one of the richest sources of copper in the world. Cobalt, selenium, silver, and gold are also produced.
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Omagh
Omagh , town (1991 pop. 14,627), Omagh dist., W Northern Ireland, on the Strule River. The town is a farm market. Dairy products are processed and shirts are manufactured. The discovery in 1995 of silver and gold in the bogs of Omagh led to a conflict between proponents of economic growth and advoca...
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reliquary
reliquary , receptacle containing the relics of saints and other sacred objects of the Christian religion. Reliquaries were often designed in shapes that reflected the nature of their contents, such as hands, shoes, buildings, and heads. They were richly decorated with gold, silver, enamel, and jewe...
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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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