Atacamite is a copper halide mineral: a copper(II) chloride hydroxide with formula Cu<sub>2</sub>Cl(OH)<sub>3</sub>. It was first described from deposits in the Atacama Desert of Chile in 1802 by Dmitri Alekseyevich Golitsyn.
The mineral has been found as a pigment in sculpture, manuscripts, maps, and frescoes discovered in Eurasia, Russia, and Persia.
Biomineral
Atacamite occurs as a biomineral in the jaws of bloodworms.
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Atacamite-235102.jpg|Atacamite prisms from Chile
Harvard Museum of Natural History. Atacamite. Miraflores Mine, Tierra Amarilla, Atacama, Chile (DerHexer) 2012-07-20.jpg|Atacamite from Chile displayed in the Harvard Museum of Natural History
Atacamite-168148.jpg|Atacamite from Mt. Gunson, South Australia
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