Celestine
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Mineral NameCelestine
Chemical FormulaSrSO₄
Mohs Hardness3
Crystal Systemorthorhombic
Lustervitreous
Streak Colorwhite
Cleavageperfect on {001}, good on {210}
Fractureuneven
Specific Gravity3.96
Colorslight blue, greenish-blue
Transparencytranslucent
Type LocalityPoland
Mineral GroupSulfates
Usescollector, source of strontium
Associated Mineralssulfur, gypsum, calcite, aragonite
Raritycommon
Description
A striking cluster of light blue to greenish-blue, elongated prismatic crystals forming a radiating aggregate on a dark, rough matrix. The crystals are translucent with a distinct vitreous luster.
Geological Context
Celestine commonly forms in sedimentary rocks, particularly limestones and dolomites, and in evaporite deposits. It can also be found in hydrothermal veins.
