Datolite
Image: SKas (CC BY-SA 4.0)
Mineral NameDatolite
Chemical FormulaCaB(SiO4)(OH)
Mohs Hardness5
Crystal Systemmonoclinic
Streak Colorwhite
Cleavagepoor on {001}
Fractureconchoidal to uneven
Specific Gravity2.95
Colorspale green, white, reddish-brown
Transparencytranslucent
Type LocalityDalnegorsk deposit, Primorsky Krai, Russian Federation
Mineral GroupNesosilicate
Usescollector, minor gemstone
Associated Mineralscalcite
Rarityuncommon
Description
A specimen featuring pale green, blocky datolite crystals embedded in a lighter matrix, with small white acicular calcite crystals in a vug and some reddish-brown staining.
Geological Context
Datolite typically forms in cavities within mafic igneous rocks or in skarn deposits, often associated with hydrothermal activity. The Dalnegorsk deposit is known for its skarn mineralization.
