Chalcopyrite Chalcopyrite Chalcopyrite ( ) is a copper iron sulfide mineral that crystallizes in the tetragonal system. It has the chemical formula CuFeS. It has a brassy to golden yellow color and a hardness of 3.5 to 4 on the Mohs scale. Its streak is diagnostic as green tinged black. On exposure to air, chalcopyrite oxidises to a variety of oxides, hydroxides and sulfates. Associated copper minerals include the sulfides bornite (CuFeS), chalcocite (CuS), covellite (CuS), digenite (CuS); carbonates such as malachite and azurite, and rarely oxides such as cuprite (CuO). Chalcopyrite is rarely found in association with native copper. Natural
Ore Mountain Basin Ore Mountain Basin The Ore Mountain Basin or Erzgebirge Basin () is a natural region in the German federal state of Saxony, that is part of the Saxon Lowland. To the north it borders on the Mulde Loess Hills and to the south on several natural regions in the Saxon Highlands and Uplands. The basin is a structural depression running from northeast to southwest in the Ore Mountain peneplain that is filled with Devonian and Carboniferous sediments. The main communications from the Ore Mountains follow the valleys downhill and are collected by a major routeway to the north that follows