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trigonaluncommonSilicates
Dravite
NaMg₃Al₆(Si₆O₁₈)(BO₃)₃(OH)₃(OH)
This specimen features dark brown to black, prismatic dravite crystals with well-defined, fully terminated tops, displaying a characteristic vitreous luster.
Dravite Physical Properties
Mohs Hardness
7Crystal System
trigonalLuster
vitreousStreak Color
whiteCleavage
indistinct to poorFracture
conchoidalSpecific Gravity
3.05Colors
brown, yellowish-brown, dark brown, black, green, blueTransparency
transparent to opaqueType Locality
Pikarec, Czech RepublicMineral Group
SilicatesUses
collector's specimens, gemstone (rarely), scientific researchAssociated Minerals
quartz, feldspar, micaRarity
uncommonGeological Context
Dravite commonly forms in magnesium-rich metamorphic rocks like schists and gneisses, and can also be found in some pegmatites and hydrothermal veins.
