Peretaite

peretaite

klebelsbergite

valentinite

kermesite

Images

Formula: CaSb3+4O4(SO4)2(OH)2.2H2O
Sulphate, antimony-bearing mineral
Crystal system: Monoclinic
Specific gravity: 4.06 calculated for the ideal formula
Hardness: 3½ to 4
Colour: Colourless, can be pink due to encrustations of valentinite
Environments

Sedimentary environments
Hydrothermal environments

Peretaite is a rare mineral, formed by the action of sulphuric acid solutions on stibnite in the oxidised zone of a limestone-hosted hydrothermal antimony-bearing deposit. Associated minerals include stibnite, pyrite, kermesite, sulphur, valentinite, onoratoite, klebelsbergite, gypsum, calcite and quartz (HOM).

Localities

At the type locality, the Pereta Mine, Scansano, Grosseto Province, Tuscany, Italy, peretaite occurs, in small quantities, as aggregates of tabular crystals in the geodes of a deeply silicified limestone, and also in the cavities of columnar stibnite. Crystals of peretaite are associated with acicular crystals of klebelsbergite, stibnite, quartz, calcite, pyrite, valentinite, kermesite, sulphur and gypsum. Aggregates of klebelsbergite crystals and rarely of peretaite are often red from incrustations of valentinite. Unlike klebelsbergite, which was found rather abundantly in the fissures of the stibnite veinlets, peretaite occurs closer to the boundary with limestones. Peretaite, as well as klebelsbergite, has apparently been formed by the action of sulphuric acid on stibnite; the source of the calcium in peretaite is likely the limestone of the countrv rock (AM 65.936-939).
Peretaite from the Pereta Mine - Image

Back to Minerals