Cubanite | |
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Striated, cyclically-twinned cubanite crystals from the Chibougamau mines of Quebec. (size: 1.5 x 1.3 x 1.0 cm) |
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General | |
Category | Sulfide mineral |
Chemical formula | CuFe2S3 |
Strunz classification | 02.CB.55a |
Crystal symmetry | Orthorhombic (2/m 2/m 2/m) - dipyramidal |
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 |
Crystal system | Orthorhombic |
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 | [1][2][3] |
Cubanite is a yellow mineral of copper, iron, and sulfur, CuFe2S3.[3]
Cubanite was first described in 1843 for an occurrence in the Mayarí-Baracoa Belt, Oriente Province, Cuba.[1]
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.[2] It has also been reported from carbonaceous chondrite meteorites.[2]