The Collaborative International Dictionary
Atacamite \A*tac"a*mite\, n. [From the desert of Atacama, where found.] (Min.) An oxychloride of copper, usually in emerald-green prismatic crystals.
n. (context mineral English) A green copper(II) chloride hydroxide mineral, polymorphous with botallackite.
It was first described for deposits in the Atacama Desert of Chile in 1801.
Atacamite is polymorphous with botallackite, clinoatacamite, and paratacamite. Atacamite is a comparatively rare mineral, formed from primary copper minerals in the oxidation or weathering zone of arid climates. It has also been reported as a volcanic sublimate from fumarole deposits, as sulfide alteration products in black smokers and as alteration of ancient bronze and copper artefacts. It occurs in association with cuprite, brochantite, linarite, caledonite, malachite, chrysocolla and its polymorphs.
It has been shown that atacamite is a component of the jaws of some Glycera species.