Formula: PbGa3(AsO4)(SO4)(OH)6
Arsenate, beudantite group, gallium-bearing mineral
Specific gravity: 4.87 calculated
Hardness: 4
Streak: Pale yellow, white
Colour: Pale yellow, greenish, cream-coloured

Hydrothermal environments

Gallobeudantite was approved in 1994, but to date (June 2022) it has been reported only from the type locality.


At the type locality, the Tsumeb Mine, Tsumeb, Oshikoto Region, Namibia, gallobeudantite occurs as a rare secondary mineral in vugs in a single, blackish specimen of massive copper ore, approximately 5 cm across. The host material consists mainly of aligned inclusions of renierite, up to 3 mm long, in a granular matrix consisting largely of a germanite-like mineral. The renierite contains irregular inclusions of gallite up to 75 microns across, and one end of the section contains inclusions of antimony-free gallium-bearing tennantite. A thin rim of chalcocite emphasises the granular texture of the germanite-like phase, and all minerals are cut by irregular, hairline veinlets of chalcocite. Disseminated on the surface of the specimen are local, minute patches of hematite and goethite, sparse crystals of stolzite, and dots of spongy mercury-bearing silver. One end of the specimen has a thin, discontinuous veinlet, about 1 mm long, of otjisumeite (CM34: 1305-1315).

Back to Minerals