Tongbaite
| Tongbaite | |
|---|---|
| General | |
| Category | Carbide mineral |
| Formula (repeating unit) | Cr3C2 |
| Strunz classification | 01.BA.15 |
| Crystal symmetry |
Orthorhombic dipyramidal H-M symbol: (2/m 2/m 2/m) Space group: P nma |
| Unit cell | a = 5.52 Å, b = 11.48 Å, c = 2.82 Å; Z = 4 |
| Identification | |
| Color | Pale brownish yellow; pale violet in reflected light |
| Crystal habit | Prismatic crystals, pseudohexagonal |
| Crystal system | Orthorhombic |
| Tenacity | Brittle |
| Mohs scale hardness | 9.6 |
| Luster | Metallic |
| Diaphaneity | Opaque |
| Specific gravity | 6.64 calculated |
| References | [1][2][3] |
Tongbaite is a rare mineral that has the chemical formula Cr3C2, or chromium carbide.
It was first described in 1983 for an occurrence in Liu village, Tongbai, Henan Province, China and named for the locality.[2] It occurs in an ultramafic rock deposit.[1] It has also been reported from the Tibet Autonomous Region and from the Isovsky District in the Urals of Russia.[2]
References
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