Zincochromite
| Zincochromite | |
|---|---|
Top: Zincochromite from Russia. Bottom: ZnCr2O4 (Fd3̅m) crystal structure showing Zn on tetrahedral A sites (gray), Cr on octahedral B sites (magenta), and O (red). | |
| General | |
| Category | Minerals |
| Formula | ZnCr2O4 |
| IMA symbol | Zchr |
| Strunz classification | 4.BB.05 |
| Crystal system | Cubic |
| Crystal class | Hexoctahedral (m3m) H-M symbol: (4/m 3 2/m) |
| Space group | Fd3m |
| Unit cell | a = 8.32 Å; Z = 8 |
| Identification | |
| Color | Brownish black |
| Crystal habit | Zoned euhedral crystals with hexagonal outline |
| Mohs scale hardness | 5.8 |
| Luster | Semimetallic |
| Streak | Brown |
| Diaphaneity | Opaque, translucent in thin slivers |
| Optical properties | Isotropic |
| Other characteristics | Weakly paramagnetic |
| References | |
Zincochromite is a zinc chromium oxide mineral with the formula ZnCr2O4. It is the zinc analogue of chromite, hence the name. It was first described in 1987 as an occurrence in a uranium deposit near Lake Onega, Russia. It has also been reported from Dolo Hill, New South Wales, Australia, and from the Tarkwa Mine in the Ashanti gold belt of Ghana.