Tetrahedrite is a copper-antimony sulfosalt that forms the antimony end-member of an extensive solid-solution series with tennantite (As-end). It is the most abundant and widely distributed sulfosalt and a significant ore of copper, silver and antimony.
Properties
- Formula: Cu6(Cu4(Fe,Zn)2)Sb4S13
- Crystal system: Isometric (Cubic)
- Hardness: 3 – 4.5
- Color: Steel-gray to iron-black, sometimes with bluish tarnish
- Streak: Black to brown
- Luster: Metallic
- Cleavage: None
- Density: 4.6 – 5.2 g/cm³
Occurrence in China
Tetrahedrite is widespread in Yunnan and Sichuan Cu-Pb-Zn-Ag deposits (Lanping, Gejiu) and in the Hunan W-Sn-Sb belt. Globally noted at Cornwall (UK), Bolivia and Peru.
Identification
Sharp tetrahedral crystal habit (when present) is the species’ namesake feature. Cubic system + dark steel-gray color + tetrahedron form distinguish it from galena (cubic crystals) and chalcopyrite (brassy yellow, tetragonal).
Collector Notes
Sharp, isolated tetrahedra perched on chalcopyrite or quartz are the most desirable form. Often Ag-rich varieties (freibergite) command extra interest from silver-mineral specialists.
Found at these Localities
- Bou Azzer District (布·阿扎尔钴矿区)
- Siegerland District (西格兰铁矿区)
- Příbram (普日布拉姆银矿)
- Săcărâmb (Nagyág) (萨卡拉姆布金碲矿)
- Sweet Home Mine (甜蜜之家矿)
- Chañarcillo (查尼亚西略)
- Cripple Creek District (克里普尔克里克金矿区)
- Heqing Cu-Ag-Pb-Zn District (鹤庆铜银铅锌矿区)
- Xiaoqinling Gold Field (小秦岭金矿田)
- Ying Silver Mine (银矿(豫西银多金属矿带))
- Lanping Pb-Zn-Cu Field (兰坪铅锌铜矿田)
- Cornwall Mining District (康沃尔矿区)
- Gejiu Mine (个旧锡矿)
- Yunnan (云南)
- Sichuan (四川)
- Hunan (湖南)
