Thulite
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Mineral NameThulite
Chemical FormulaCa₂Al₃(SiO₄)₃(OH)
Mohs Hardness6
Crystal Systemorthorhombic
Lustervitreous
Streak Colorwhite
Cleavageperfect on {010}
Fractureuneven
Specific Gravity3.18
Colorspink, rose-red, reddish-violet
Transparencytranslucent
Type LocalityTvedestrand, Norway
Mineral GroupSilicates
Usesjewelry, carving material, collector
Associated Mineralsquartz, feldspar, hornblende, garnet
Rarityuncommon
Description
This specimen displays a vibrant rose-pink to reddish color, characteristic of Thulite, with a granular texture and some lighter, possibly crystalline, areas that exhibit a subtle sparkle. The piece is a rough, massive aggregate.
Geological Context
Thulite is a manganese-rich variety of zoisite that typically forms in metamorphic rocks, often associated with regional metamorphism of calcium-rich sedimentary rocks or hydrothermal alteration in manganese-bearing environments.
