Goudeyite Locality: Santa Lucia Prospect, Muravera, Cagliari Province, Sardinia, Italy Green acicular xls of Goudeyite. Field of view 10 mm. Specimen and photo Leon Hupperichs. — Photo: Leon Hupperichs · CC BY-SA 3.0
Goudeyite
Goudeyite is an IMA-recognized mineral species in the arsenate class, with the chemical formula Cu₆Al(AsO₄)₃(OH)₆·3H₂O.
It crystallizes in the hexagonal crystal system. It is a member of the Mixite structural group.
Key properties: Mohs hardness 3–4; specific gravity 3.5; optically uniaxial.
IMA symbol Gdy, IMA status: approved, named in 1978.
Found as a rare secondary mineral in a hydrothermal Cu–Sn orebody in rhyolite porphyries and breccias (Majuba Hill, Nevada, USA).
It is found associated with Olivenite, clinoclase, cornwallite, strashimirite, scorodite, pharmacosiderite, arthurite, metazeunerite, chalcanthite, chrysocolla, spangolite.
The mineral was named to honor Hatfield Goudey (1906–1985), American economic geologist, mineral collector and dealer in microscopic specimens, San Mateo, California, USA.