Bultfonteinite
Image: <a href="//commons.wikimedia.org/wiki/User:Iifar" title="User:Iifar">Ivar Leidus</a> (CC BY-SA 4.0)
Mineral NameBultfonteinite
Chemical FormulaCa₂SiO₃(OH)₄F₂
Mohs Hardness4.5
Crystal Systemmonoclinic
Lustervitreous
Streak Colorwhite
Cleavageperfect on {001}
Fractureuneven
Specific Gravity2.73
Colorswhite, colorless, pale pink, pale yellow
Transparencytranslucent
Type LocalityShijiangshan mine, Linxi, Chifeng City, Inner Mongolia, China
Mineral Groupsilicates
Usescollector
Associated Mineralsdatolite
Rarityuncommon
Description
This specimen features radiating aggregates of acicular to bladed, translucent white Bultfonteinite crystals, forming a spiky, fluffy cluster on a matrix.
Geological Context
Bultfonteinite is a rare calcium silicate mineral typically found in hydrothermally altered basalts, kimberlites, and other alkaline igneous rocks, often in vugs and cavities.
