Okenite
Image: <a href="//commons.wikimedia.org/wiki/User:Archaeodontosaurus" title="User:Archaeodontosaurus">Didier Descouens</a> (CC BY-SA 4.0)
Mineral NameOkenite
Chemical FormulaCaSi2O5·2H2O
Mohs Hardness4.5
Crystal Systemtriclinic
Lusterpearly
Streak Colorwhite
Cleavageperfect on {001}
Fractureuneven
Specific Gravity2.3
Colorswhite, off-white
Transparencytranslucent
Type LocalityKhandivali, Maharashtra, India
Mineral GroupSilicates
Usescollector
Associated Mineralsapophyllite, stilbite, heulandite, gyrolite, prehnite, calcite
Rarityuncommon
Description
This specimen features delicate, fluffy, white cotton-ball-like aggregates of okenite crystals nestled within a geode-like cavity of a darker host rock, with some granular white material surrounding the okenite clusters.
Geological Context
Okenite is a secondary mineral that forms in the vesicles and cavities of basaltic rocks, often in association with zeolites and other hydrothermal alteration products.
