Brazilianite
Image: <a href="//commons.wikimedia.org/wiki/User:Archaeodontosaurus" title="User:Archaeodontosaurus">Didier Descouens</a> (CC BY-SA 3.0)
Mineral NameBrazilianite
Chemical FormulaNaAl₃(PO₄)₂(OH)₄
Mohs Hardness5.5
Crystal Systemmonoclinic
Lustervitreous
Streak Colorwhite
CleavageGood on {010}, distinct on {110} and {100}
Fractureuneven to conchoidal
Specific Gravity2.98
Colorsyellow-green, green, yellowish-brown, colorless
Transparencytransparent
Type LocalityConselheiro Pena, Doce valley, Minas Gerais, Southeast Region, Brazil
Mineral GroupPhosphates
Usesjewelry, collector
Associated Mineralsquartz, muscovite, albite, beryl, tourmaline, apatite
Rarityuncommon
Description
This specimen features a prominent, lustrous, yellow-green Brazilianite crystal with well-defined faces, partially embedded in a matrix of smaller, granular, lighter yellow-green to white crystals.
Geological Context
Brazilianite is a rare phosphate mineral typically found in granite pegmatites, often forming in late-stage hydrothermal veins or pockets. It is a secondary mineral resulting from the alteration of primary phosphate minerals.
