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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...

Obuasi

(Encyclopedia)Obuasi ōbwäˈsē [key], town (1984 pop. 60,617), S central Ghana. Highly concentrated gold ore is mined, and there are gold-extraction plants. Gold was mined in Obuasi by indigenous peoples as early...

Idaho

(Encyclopedia)CE5 Idaho īˈdəhō [key], one of the Rocky Mt. states in the NW United States. It is bordered by Montana and Wyoming (E), Utah and Nevada (S), Oregon and Washington (W), and the Canadian province...

Au

(Encyclopedia)Au, symbol for the element gold.

San Francisco

(Encyclopedia)San Francisco săn frănsĭsˈkō [key], city (2020 pop. 873,965), coextensive with San Francisco co., W ...

Joyner-Kersee, Jackie

(Encyclopedia)Joyner-Kersee, Jackie joiˈnər-kûrˈzē [key], 1962–, American track and field athlete, b. East St. Louis, Ill. One of the world's best all-around women athletes, she won the silver medal in the h...

Biles, Simone Arianne

(Encyclopedia)Biles, Simone Arianne, 1997–, American gymnast, b. Columbus, Ohio. Known for her consistency and the high degree of difficulty of her routines, she was the first gymnast to win three consecutive wor...

Kirkland Lake

(Encyclopedia)Kirkland Lake, mining town, E Ont., Canada. An important gold-mining center, gold was discovered there in 1911 and again in the 1980s at Harker. The mining of iron ore and tourism are two other import...

Nevada

(Encyclopedia)CE5 Nevada nəvădˈə, –vä– [key], far western state of the United States. It is bordered by Utah (E), Arizona (SE), California (SW, W), and Oregon and Idaho (N). In the 20th cent. the ...

McHenry, James

(Encyclopedia)McHenry, James, 1753–1816, American political leader, b. Ireland. He emigrated to Philadelphia in 1771 and, after studying medicine under Benjamin Rush, served as a surgeon in the Continental Army i...