Arhbarite

Formula:  Cu₂(AsO₄)(OH)^.6H₂O

Origin of name:  From locality; Arhbar mine, Bou-Azzer, Morocco

Crystal system:  Monoclinic ?

Crystal class:  Unknown

Twinning:

Unit cell: a = 16.988 Å, b = 15.901 Å, c = 6.1 Å, b = 97.5°

Colour:  Blue, dark blue

Diaphaneity: Semi-transparent

Luster: Vitreous

Habit:  Spherulitic aggregates, fibrous

Hardness:

Specific gravity:

Cleavage: None

Tenacity:

Streak: Sky-blue

Synonyms/varieties:

Comments: Found as a rare secondary mineral in polymetallic hydrothermal ore deposits.