Cobaltite

Cobaltite
Cobaltite from Sweden
General
CategorySulfide mineral
FormulaCoAsS
IMA symbolCbt
Strunz classification2.EB.25
Crystal systemOrthorhombic
Crystal classPyramidal (mm2)
(same H-M symbol)
Space groupPc21b
Unit cella = 5.582 Å,
b = 5.582 Å,
c = 5.582 Å; Z = 4
Identification
ColorReddish silver white, violet steel gray to black
Crystal habitGranular to massive, rarely as striated crystals, pseudocubic.
TwinningAbout [111] creating pseudo-cubic forms and striations
CleavagePerfect on {001}
FractureUneven
TenacityBrittle
Mohs scale hardness5.5
LusterMetallic
StreakGrayish-black
DiaphaneityOpaque
Density6.33 g/cm3
References

Cobaltite is an arsenide and sulfide mineral with the mineral formula CoAsS. It is the naming mineral of the cobaltite group of minerals, whose members structurally resemble pyrite (FeS2).