Aerugite

Formula:  Ni₁₇As₆O₃₂

Origin of name:  from Latin for rust of copper, in allusion to its appearance

Crystal system:  Hexagonal

Crystal class:  -3 2/m

Twinning:

Unit cell: a = 5.951 Å, c = 27.568 Å

Colour: Green

Diaphaneity: Translucent to semitransparent

Luster:

Habit:  Massive; finely crystalline

Hardness:  4

Specific gravity:  5.85

Cleavage:  None

Tenacity:

Streak:  Light green to light blue-green

Synonyms/varieties:

Comments: Occurs as a secondary mineral in hydrothermal Ni-As-U ore deposits.