Cohenite
From Wikipedia, the free encyclopedia
| Cohenite | |
|---|---|
| General | |
| Category | Carbides |
| Chemical formula | (Fe,Ni,Co)3C |
| Strunz classification | 01.BA.05 |
| Identification | |
| Molar mass | 183.04 gm |
| Crystal system | Orthorhombic - Dipyramidal |
| Cleavage | good |
| Fracture | Brittle |
| Mohs scale hardness | 5.5–6 |
| Luster | Metallic |
| Diaphaneity | Opaque |
| Density | 7.2 – 7.65 |
| Other characteristics | Strongly magnetic |
| References | [1][2] |
Cohenite is a naturally occurring iron mineral with the chemical structure (Fe, Ni, Co)3C. This forms a hard, shiny, silver mineral which was named by E. Weinschenk in 1889 after the German mineralogist Emil Cohen, who first described and analysed it. Cohenite is found in rod-like crystals in iron meteorites. [3]
On Earth Cohenite is stable only in rocks which formed in a strongly reducing environment and contain native iron deposits. Such conditions existed in some places where molten magmas invaded coal deposits, e.g. on Disco Island in Greenland, or at the Bühl near Kassel in Germany.
Similar ironcarbides occur also in technical iron alloys and are called cementite.
[edit] References
- ^ http://www.mindat.org/min-1107.html Mindat.org Cohenite Page
- ^ http://www.webmineral.com/data/Cohenite.shtml Webmineral.com Cohenite Page
- ^ Vagn F. Buchwald: Handbook of Iron Meteorites. University of California Press, 1975
