Cu2SOrthorhombic
Chalcocite
Cu2S
SulfidesChemical FormulaCu2S
Crystal SystemOrthorhombic
Mohs Hardness2.5
Specific Gravity5.76
ColorDark gray to black
LusterMetallic
StreakGrayish black
CleavageNone
FractureConchoidal
Occurrence
Important copper ore. Found in supergene enrichment zones.