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Linnaeite

Linnaeite
Linnaeite - USGS Mineral Specimens 722.jpg
Linnaeite samples and polished section
General
Category Sulfide mineral
Thiospinel group
Spinel structural group
Formula
(repeating unit)
Co+2Co+32S4
Strunz classification 2.DA.05
Crystal system Cubic
Crystal class Hexoctahedral (m3m)
H-M symbol: (4/m 3 2/m)
Space group Fd3m
Unit cell a = 9.43 Å; Z = 8
Identification
Color Steel gray to gray violet
Crystal habit As octahedral crystals; massive, granular
Twinning On {111}
Cleavage Imperfect on {001}
Fracture Subconchoidal
Mohs scale hardness 4.5-5.5
Luster Metallic
Streak Grayish-black
Diaphaneity Opaque
Specific gravity 4.8-5.8
Alters to Tarnishes in air
References

Linnaeite is a cobalt sulfide mineral with the composition Co+2Co+32S4. It was discovered in 1845 in Västmanland, Sweden, and was named to honor Carl Linnaeus (1707–1778).

Linnaeite forms a series with polydymite, Ni+2Ni+32S4. Linnaeite is found in hydrothermal veins with other cobalt and nickel sulfides in many localities around the world.


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Wikipedia

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