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Copper. face-centered cubic (fcc) (cF4) Copper is a chemical element; it has symbol Cu (from Latin cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity ...
In Arizona, copper mining has been a major industry since the 19th century. In 2007, Arizona was the leading copper-producing state in the country, producing 750 thousand metric tons of copper, valued at $5.54 billion. Arizona's copper production was 60% of the total for the United States. Copper mining also produces gold and silver as ...
In the United States, copper mining has been a major industry since the rise of the northern Michigan copper district in the 1840s. In 2017, the US produced 1.27 million metric tonnes of copper, worth $8 billion, making it the world's fourth largest copper producer, after Chile, China, and Peru. Copper was produced from 23 mines in the US.
Tarnishes to black or green in air. Native copper is an uncombined form of copper that occurs as a natural mineral. Copper is one of the few metallic elements to occur in native form, although it most commonly occurs in oxidized states and mixed with other elements. Native copper was an important ore of copper in historic times and was used by ...
William A. Clark. The Copper Kings were industrialists Marcus Daly, William A. Clark, James Andrew Murray and F. Augustus Heinze.They were known for the epic battles fought in Butte, Montana, and the surrounding region, during the Gilded Age, over control of the local copper mining industry, the fight that had ramifications for not only Montana, but the United States as a whole.
The Chalcolithic (also called the Copper Age and Eneolithic) [a] was an archaeological period characterized by the increasing use of smelted copper. It followed the Neolithic and preceded the Bronze Age. It occurred at different periods in different areas, but was absent in some parts of the world, such as Russia, where there was no well ...
Chalcopyrite (/ ˌkælkəˈpaɪˌraɪt, - koʊ -/ [7][8] KAL-kə-PY-ryte, -koh-) is a copper iron sulfide mineral and the most abundant copper ore mineral. It has the chemical formula CuFeS 2 and crystallizes in the tetragonal system. It has a brassy to golden yellow color and a hardness of 3.5 to 4 on the Mohs scale.
Timna Valley. The Timna Valley (תִּמְנָע, Hebrew pronunciation: [timˈna (ʕ)]) is located in southern Israel in the southwestern Arava/ Arabah, approximately 30 kilometres (19 mi) north of the Gulf of Aqaba and the city of Eilat. The area is rich in copper ore and has been mined since the 5th millennium BCE.