Class : Halides
    Subclass : Oxychlorides
    Crystal system : Orthorhombic
    Chemistry : Cu₂Cl(OH)₃
    Rarity : Uncommon

Atacamite is an alteration mineral of copper deposits occurring in arid and saline conditions. It has three polymorphs : botallackite, paratacamite and clinoatacamite. It owes its name to its province of discovery : Atacama in Chile. It occurs in elongated prismatic crystals, striated along their length, in crystalline aggregates sometimes united in rosettes, and in fibrous masses, sometimes powdery. Atacamite is transparent to translucent, vivid, emerald green to blackish green, sometimes light green. Its formation in an arid and saline climate makes it a relatively widespread alteration mineral of copper by the sea : it is the secondary mineral that corrodes, for example, the brass parts of the Statue of Liberty in New York. It was once mined locally as copper ore, today its samples are exclusively intended for the collection.

In France, atacamite is described as microcrystals at Cap Garonne (Var).

No fake recorded for this species.