Celestine
Image: <a href="//commons.wikimedia.org/wiki/User:Archaeodontosaurus" title="User:Archaeodontosaurus">Didier Descouens</a> (CC BY-SA 4.0)
Mineral NameCelestine
Chemical FormulaSrSO4
Mohs Hardness3.25
Crystal Systemorthorhombic
Lustervitreous
Streak Colorwhite
Cleavageperfect on {001}, good on {210}, fair on {010}
Fractureuneven
Specific Gravity3.96
Colorswhite, colorless
Transparencytranslucent
Type LocalityHammam-Zriba Mine, Zriba-Village, Zaghouan Tunisia
Mineral GroupSulfates
Usesindustrial, collector
Associated Mineralsgypsum, anhydrite, sulfur, calcite
Raritycommon
Description
This specimen features a radiating cluster of numerous bladed to prismatic celestine crystals, predominantly white and translucent, forming a spherical or botryoidal aggregate.
Geological Context
Celestine typically forms in sedimentary rocks, particularly in evaporite deposits, limestones, and dolomites, often as a result of diagenetic replacement or precipitation from hydrothermal fluids.
