Collection: Covellite

Formula: CuS

"Extended" formula:  Cu⁺₄Cu²⁺₂(S₂)₂S₂ (Goble, 1985).

Colour: Indigo-blue or darker, inclining towards blue-black, often iridescent with purplish, deep red, and brassy-yellow reflections.

Luster: Sub-Metallic

Hardness: 1½ - 2

Specific Gravity: 4.6 - 4.76

Crystal System: Hexagonal