Barrerite
Appearance
Barrerite | |
---|---|
Barrerite from Kuiu Island, Alaska, USA. | |
General | |
Category | Zeolite |
Formula (repeating unit) | (Na,K,Ca)2Al2Si7O18·6(H2O) |
IMA symbol | Bre[1] |
Strunz classification | 9.GE.15 |
Crystal system | Orthorhombic |
Crystal class | Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m) |
Space group | Amma |
Identification | |
Color | White, pink |
Cleavage | Perfect |
Mohs scale hardness | 3 - 4 |
Luster | Vitreous-glassy |
Streak | White |
Diaphaneity | Transparent to translucent |
Specific gravity | 2.13 |
Optical properties | Biaxial (-) |
Refractive index | nα = 1.479 nβ = 1.485 nγ = 1.489 |
References | [2][3][4] |
Barrerite is a tectosilicate mineral and a member of the zeolite family. It is one of the rarer zeolites. It was named for Richard Barrer, a New Zealand-born chemist.[4]
Barrerite crystal are white to pinkish, with a vitreous-glassy luster. The crystal system is orthorhombic and is flat and tabular in appearance. It has a Mohs hardness of 3 to 4 and its cleavage is perfect. Barrerite has a white streak and a density of 2.13.
It was first described in 1974 for an occurrence in Sardinia at Sant' Efisio Tower on Cape Pula in Cagliari Province.[4] It has also been reported from Rocky Pass, Kuiu Island, Alaska, and a few other localities.
References
[edit]- ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
- ^ "Mineralienatlas - Fossilienatlas". www.mineralienatlas.de. Retrieved 2023-06-29.
- ^ "Barrerite Mineral Data". webmineral.com. Retrieved 2023-06-29.
- ^ a b c "Barrerite".
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