Peretaite Field of view: 2 mm Locality: Pereta Mine (TL), Scansano, Grosseto Province, Tuscany, Italy ( locality at mindat.org ) — Photo: Henk Smeets – tomeikminerals.com · CC BY 4.0
Peretaite
A calcium-antimony sulfate named for its occurrence at Pereta, Tuscany.
Intro adapted from Wikipedia (CC BY-SA).
Peretaite is an IMA-recognized mineral species in the sulfate class, with the chemical formula CaSb³⁺₄O₄(SO₄)₂(OH)₂·2H₂O.
It crystallizes in the monoclinic crystal system (space group C2/c).
Key properties: specific gravity 3.8; Vitreous luster; optically biaxial.
IMA symbol Pta, IMA status: approved, named in 1979.
Of rare occurrence, formed by the action of H2 SO4 solutions on stibnite in the oxidized zone of a limestone-hosted hydrothermal antimony-bearing deposit.
It is found associated with Stibnite, pyrite, kermesite, sulfur, valentinite, onoratoite, klebelsbergite, gypsum, calcite, quartz.
The name refers to its occurrence at the Pereta mine, Italy.