Liroconite

Formula:  Cu₂Al(AsO₄)(OH)₄ ^. 4H₂O

Origin of name:  From Greek for pale and powder

Crystal system:  Monoclinic

Crystal class:  2/m

Twinning: 

Unit cell: a = 12.67 Å, b = 7.58 Å, c = 9.90 Å, β = 91.3°

Colour:  Sky-blue to green

Diaphaneity: 

Luster:  Vitreous to resinous

Habit:  Crystals flattened and wedge-shaped, striated; subgranular groups; coarse granular

Hardness:  2 to 2.5

Specific gravity:  2.93 to 3.01

Cleavage:  2; {110} and {011} indistinct

Tenacity:  Conchoidal to uneven; brittle

Streak: 

Synonyms/varieties:

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