Diaphorite

Formula:  Pb₂Ag₃Sb₃S₈

Origin of name:   From Greek for difference, as being distinct from freieslebenite

Crystal system:   Monoclinic

Crystal class:   2/m

Twinning: on {120} and {241}

Unit cell: a = 15.86 Å, b = 17.91 Å, c = 5.90 Å, b = 116.3°

Colour:   Steel-gray

Diaphaneity: Opaque

Luster:   Metallic

Habit:   Crystals prismatic, striated parallel to elongation [001]; may be complex

Hardness:   2.5 to 3

Specific gravity:   5.97

Cleavage:   None

Tenacity:   Conchoidal to uneven fracture; brittle

Streak: 

Synonyms/varieties:

Comments: Found in hydrothermal veins with other sulphides formed at moderate temperature