Alabandite
| Alabandite | |
|---|---|
Group of octahedral alabandite crystals partially coated with pink rhodochrosite, from Uchucchacua Mine, Oyon, Lima, Peru (size: 60 mm × 59 mm × 46 mm, 204 g) | |
| General | |
| Category | Sulfide mineral |
| Formula | MnS |
| IMA symbol | Abd |
| Strunz classification | 2.CD.10 (10 ed) II/C.15-30 (8 ed) |
| Dana classification | 2.8.1.4 |
| Crystal system | Cubic |
| Crystal class | Hexoctahedral (m3m) H-M symbol: (4/m 3 2/m) |
| Space group | Fm3m |
| Unit cell | a = 5.2236 Å; Z = 4 |
| Identification | |
| Color | black, steelgray, brownish-black |
| Crystal habit | mostly massive or granular; cubic or octahedral crystals to 1 cm |
| Twinning | Lamellar || {111} |
| Cleavage | Perfect on {100} |
| Fracture | Irregular, uneven |
| Tenacity | Brittle |
| Mohs scale hardness | 3.5 to 4 |
| Luster | Sub-metallic |
| Streak | Green |
| Diaphaneity | Opaque, translucent in thin fragments |
| Specific gravity | 4.053 |
| Optical properties | Isotropic |
| Refractive index | n = 2.70 |
| References | |
Alabandite or alabandine, formerly known as manganese blende or bluemenbachite is a rarely occurring manganese sulfide mineral. It crystallizes in the cubic crystal system with the chemical composition Mn2+S and develops commonly massive to granular aggregates, but rarely also cubic or octahedral crystals to 1 cm.