Fluor-uvite
Mineral CaMg3(Al5Mg)(Si6O18)(BO3)3(OH)3F
Also called Uvite
About it
Calcium-magnesium tourmaline in short, stubby brown to green crystals in marble; Brumado, Brazil, and Gouverneur, New York, are known localities.
- Type
- Mineral
- Group
- Silicate (cyclosilicate), tourmaline group
- Formula
- CaMg3(Al5Mg)(Si6O18)(BO3)3(OH)3F
- Hardness (Mohs)
- 7.5
- Specific gravity
- 3.01–3.09
- Streak
- white
- Lustre
- vitreous (glassy)
- Crystal system
- Trigonal
- Colours
- brown, green, black, red-brown
- Transparency
- transparent, translucent, opaque
- Cleavage and fracture
- indistinct; conchoidal fracture
Typical values: real specimens vary. For more, see mindat.org.