mineral
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
AI-generated identification · may be incorrectHardness of 6 to 6.5 on the Mohs scale, pale green to yellow-green color, vitreous to pearly luster, and orthorhombic crystal system. It often displays a botryoidal or stalactitic habit.
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Physical properties
Hardness of 6 to 6.5 on the Mohs scale, pale green to yellow-green color, vitreous to pearly luster, and orthorhombic crystal system. It often displays a botryoidal or stalactitic habit.
Formation & geological history
Forms as a secondary mineral in amygdules of basaltic rocks, hydrothermal veins, and low-grade metamorphic environments.
Uses & applications
Used primarily as a gemstone in jewelry, often cut into cabochons, and prized by mineral collectors for its unique botryoidal formations.
Geological facts
Prehnite was the first mineral to be named after a person, Colonel Hendrik von Prehn, who discovered it in South Africa in the 18th century.
Field identification & locations
Identified in the field by its distinct apple-green color, botryoidal texture, and association with zeolites or basalt. Commonly found in South Africa, Mali, Australia, and the US.
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Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
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Granite
Granite (Phaneritic intrusive igneous rock)
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