Native copper (Cu) is metallic copper in pure crystalline form. The Keweenaw Peninsula (Michigan) supplied the world’s largest historical native-copper bonanza, including the famous “Ontonagon Boulder” weighing 1,680 kg. Native copper forms in basaltic lava flows, oxidized cap zones of copper deposits, and hydrothermal veins.
Key Facts
- Mohs hardness 2.5–3.
- Isometric; arborescent dendritic and crystalline habits.
- Specific gravity 8.96.
- Tarnishes brown to green (oxide and patina) on exposure.
- Major historical source for ancient bronze metallurgy.
Notable Localities
Keweenaw Peninsula (Michigan, USA) is the world standard. Mt. Lyell (Tasmania) and Atacama (Chile) yield secondary collector material.
Found at these Localities
- Cornwall Mining District (康沃尔矿区)
- Chuquicamata (丘基卡马塔铜矿)
- Bisbee (Warren District) (比斯比铜矿)
Available Products of Copper (Native)
4 available specimens
