Cubanite
| Cubanite | |
|---|---|
Striated, cyclically-twinned cubanite crystals from the Chibougamau mines of Quebec. (size: 1.5 x 1.3 x 1.0 cm)
|
|
| General | |
| Category | Sulfide mineral |
|
Formula (repeating unit) |
CuFe2S3 |
| Strunz classification | 2.CB.55a |
| Crystal system | Orthorhombic |
| Crystal class | Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m) |
| Space group | Pcmn |
| Unit cell | a = 6.467(1) Å, b = 11.117(1) Å, c = 6.231(2) Å; Z = 4 |
| Identification | |
| Color | Bronze to brass-yellow |
| Crystal habit | Crystals elongated to thick tabular, striated also massive |
| Twinning | Common with twin plane {110} in pairs, also as fourlings and pseudohexagonal sixlings |
| Cleavage | Parting on {110} and {130} |
| Fracture | Conchoidal |
| Mohs scale hardness | 3.5-4 |
| Luster | Metallic |
| Streak | Black |
| Diaphaneity | Opaque |
| Specific gravity | 4.0-4.2 |
| Optical properties | Distinctly anisotropic on polished surface |
| Other characteristics | Strongly magnetic |
| References | |
Cubanite is a yellow mineral of copper, iron, and sulfur, CuFe2S3.
Cubanite was first described in 1843 for an occurrence in the Mayarí-Baracoa Belt, Oriente Province, Cuba.
Cubanite occurs in high temperature hydrothermal deposits with pyrrhotite and pentlandite as intergrowths with chalcopyrite. It results from exsolution from chalcopyrite at temperatures below 200 to 210 °C. It has also been reported from carbonaceous chondrite meteorites.
...
Wikipedia