Hydrated sulphate containing hydroxyl
Specific gravity: 2.29
Colour: Turquoise-green, pale blue, bluish grey, colourless in transmitted light
Solubility: Slowly soluble in cold dilute acids
Chalcoalumite is a rare secondary mineral in the
oxidised portions of copper deposits (Webmin). It alters to
At the Mbobo Mkulu Cave, Mbombela, Ehlanzeni District, Mpumalanga, South Africa, chalcoalumite is associated with mbobomkulite and hydrombobomkulite (HOM).
At the type locality, the Holbrook mine, Copper Queen Mine, Queen Hill, Bisbee, Cochise County, Arizona, USA, chalcoalumite forms crusts from one to ten millimeters thick on a brown limonite-like material. Malachite and azurite were deposited on the limonite before the chalcoalumite. Some of the specimens are stalactites of limonite completely covered with a layer of chalcoalumite (AM 10.79-83). Other associates include cuprite and goethite (HOM).
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