Formula: Cu2Cl(OH)3
Halide, atacamite group, a monoclinic paramorph of orthorhombic atacamite and monoclinic botallackite
Specific gravity: 3.77 calculated
Hardness: 3
Streak: Green to white
Colour: Green to dark greenish black, greenish blue

Sedimentary environments
Hydrothermal environments

Clinoatacamite is a secondary alteration product of copper ores (Webmin).


At Endeavour 26, Northparkes Mine Project, Goonumbla, Kennedy county, New South Wales, Australia, clinoatacamite occurs in sheaf-like groups of thin green plates or as densely packed plates forming botryoidal masses (AJM 10.2.54).

At the Telfer Mine, Rudall River District, East Pilbara Shire, Western Australia, blue-green crystal groups less than 200 microns across of fine-grained clinoatacamite were found on a specimen of sandstone. The clinoatacamite encrusts quartz crystals on a vein wall that is also encrusted by ankerite, iron oxide pseudomorphs after 1 mm pyrite octohedra, and tufts of fine fibrous malachite crystals about 200 microns across. Acicular dark green malachite crystals less than 1 mm long occur in cavities and veins in the sample (AJM 12.1.35).

At the Sierra Gorda district, Antofagasta Province, Antofagasta, Chile, clinoatacamite is associated with atacamite, zinc-bearing paratacamite, caracolite, schwartzembergite, osarizawaite-beaverite and boleite (HOM).

At the type locality, the Chuquicamata mine, Chuquicamata District, Calama, El Loa Province, Antofagasta, Chile, clinoatacamite occurs as an oxidation product of other copper minerals. Associated minerals include atacamite, paratacamite, gypsum and alunite (HOM).

The Kali Kafi mine, Anarak District, Nain County, Isfahan Province, Iran. Three specimens from this locality, labelled "anarakite" (aka herbertsmithite) proved to be clinoatacamite. Clinoatacamite has been found in specimens from several localities, and coexists with paratacamite in the holotype specimen of paratacamite (CM 34.61-72).

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