chalcocite
chalcocite
A monoclinic mineral, 96[Cu2S]; pseudohexagonal, metallic gray-black with blue to green tarnish; sp gr, 5.5 to 5.8; a secondary vein mineral; an important source of copper.; chalcosine; beta chalcocite; vitreous copper; vitreous copper ore.
A sulphide mineral of copper common in the zone of secondary enrichment.