Mineralpedia Details for Glaucophane
Glaucophane
- Formula
- [box]Na2(Mg3Al2)Si8O22(OH)2
- Crystal System
- Monoclinic
- Crystal Habit
- Massive - Fibrous, Columnar, Granular
- Cleavage
- Good, Good, None
- Luster
- Vitreous - Pearly
- Color
- gray, bluish black, lavender blue, azure blue
- Streak
- grayish blue
- Class
- Monoclinic - Prismatic
- Fracture
- Brittle - Conchoidal
- Hardness
- 6-6.5
- WebMineral
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- Mindat
- View Glaucophane
Glaucophane from San Benito Co., California, United States
Bluish black splintery and bladed crystals to 2cm in a tight packed aggregate.
Click thumbnail images for larger view.
Glaucophane from Russian River, Cloverdale, Mendocino Co., California, United States
Glaucophane prismatic crystals to 1cm or more at random orientations about matrix.
Click thumbnail images for larger view.