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Copper mining in the Upper Peninsula boomed, and from 1845 until 1887 (when it was exceeded by Butte, Montana) the Michigan Copper Country was the nation's leading producer of copper. In most years from 1850 through 1881, Michigan produced more than three-quarters of the nation's copper, and in 1869 produced more than 95% of the country's copper.
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 ...
Azurite or Azure spar [5]: 14 is a soft, deep-blue copper mineral produced by weathering of copper ore deposits. During the early 19th century, it was also known as chessylite, after the type locality at Chessy-les-Mines near Lyon, France. [3]
Following is a list of minerals that serve as copper ores in the copper mining ... Formula % Copper when pure Chalcopyrite: CuFeS 2: 34.5 Chalcocite: Cu 2 S: 79.8 ...
The Old Copper complex or Old Copper culture is an archaeological culture from the Archaic period of North America's Great Lakes region. Artifacts from some of these sites have been dated from 6500 to 1580 BCE. [1][2][page needed] It is characterized by widespread copper artifacts, including tools and weapons, as well as ornamental objects.
Minecraft "Perhaps the biggest stroke of genius in Minecraft". [67] This red mineral serves as in-game wiring, letting players lay down logic circuitry that controls pistons, minecarts and other dynamic elements in the game. [67] It is found as ore in deep caves.
Thus, for example, copper was so abundant 5000 years ago, occurring in pure form as well as in highly concentrated copper ores, that prehistoric peoples were able to collect and process it with very basic technology. As of the early 21st century, copper is commonly mined from ores that contain 0.3–0.6% copper by weight.
Chalcocite (/ ˈkælkəˌsaɪt /), [6][7] copper (I) sulfide (Cu 2 S), is an important copper ore mineral. It is opaque and dark gray to black, with a metallic luster. It has a hardness of 2.5–3 on the Mohs scale. It is a sulfide with a monoclinic crystal system. The term chalcocite from the Greek khalkos, meaning "copper".