Category Arsenate minerals Crystal system Monoclinic | Strunz classification 8.DF.20 Space group I2/a | |
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Formula
(repeating unit) Cu2Al[(OH)4|AsO4]·4(H2O) Crystal class Prismatic (2/m)
(same H-M symbol) | ||
Liroconite is a complex mineral: Hydrated copper aluminium arsenate hydroxide, with the formula Cu2Al[(OH)4|AsO4]·4(H2O). It is a vitreous monoclinic mineral, colored bright blue to green, often associated with malachite, azurite, olivenite, and clinoclase. It is quite soft, with a Mohs hardness of 2 - 2.5, and has a specific gravity of 2.9 - 3.0.
It was first identified in 1825 in the tin and copper mines of Devon and Cornwall, England. Although it remains quite rare it has subsequently been identified in a variety of locations including France, Germany, Australia, New Jersey and California.
The type locality for Liroconite is Wheal Gorland in St Day, Cornwall in the United Kingdom.
It occurs as a secondary mineral in copper deposits in association with olivenite, chalcophyllite, clinoclase, cornwallite, strashimirite, malachite, cuprite and limonite.