Alurgite
Image: <a href="//commons.wikimedia.org/wiki/User:Archaeodontosaurus" title="User:Archaeodontosaurus">Didier Descouens</a> (CC BY-SA 4.0)
Mineral NameAlurgite
Chemical FormulaK(Al,Mn)₂(AlSi₃O₁₀)(OH)₂
Mohs Hardness2
Crystal Systemmonoclinic
Lusterpearly
Streak Colorwhite
Cleavageperfect basal (001)
Fractureuneven
Specific Gravity2.85
Colorsreddish-purple, magenta, violet-red
Transparencytranslucent
Type LocalityPrabornaz Mine (ex Praborna Mine), Saint-Marcel, Aosta Valley, Italy
Mineral GroupPhyllosilicates
Usescollector's mineral
Associated Mineralsquartz, rhodonite, braunite, piemontite
Rarityuncommon
Description
This specimen displays vibrant reddish-purple to magenta flaky crystals of alurgite, exhibiting a pearly luster, embedded within a lighter, grayish-white metamorphic matrix.
Geological Context
Alurgite is a manganese-rich variety of muscovite that forms in manganese-rich metamorphic rocks, typically under conditions of regional metamorphism.
