Coloradoite

Formula:  HgTe

Origin of name:  Locality; Colorado

Crystal system:  Cubic

Crystal class:  -43m

Twinning:

Unit cell: a = 6.453 Ǻ

Colour:  Iron-black

Diaphaneity: Opaque

Luster:  Metallic

Habit:  Massive, granular

Hardness:  2.5f

Specific gravity:  8.07 to 8.63

Cleavage:  None

Tenacity:  Subconchoidal to uneven; brittle

Streak:

Synonyms/varieties:

Comments: Found in hydrothermal tellurium-bearing precious metal veins