Saliotite
Saliotite | |
---|---|
General | |
Category | Silicate mineral |
Formula (repeating unit) |
(Li,Na)Al3 (AlSi3O10)(OH)5 |
Strunz classification | 9.EC.60 |
Crystal system | Monoclinic |
Crystal class |
Prismatic (2/m) H-M symbol: (2/m) |
Space group | C2/m |
Unit cell |
a = 5.15 Å, b = 8.91 Å c = 23.83 Å; β = 94.23°; Z = 4 |
Identification | |
Color | Colorless to white |
Cleavage | Perfect on {001} |
Mohs scale hardness | 2 - 3 |
Luster | Pearly |
Streak | White |
Diaphaneity | Transparent |
Specific gravity | 2.75 |
Optical properties | Biaxial (-) |
Refractive index | nα = 1.580 - 1.590 nβ = 1.580 - 1.590 nγ = 1.590 - 1.600 |
Birefringence | δ = 0.010 |
2V angle | 30° to 50° |
References | [1][2] |
Saliotite is a rare colorless to pearl white phyllosilicate mineral in the smectite group with formula (Li,Na)Al3 (AlSi3O10)(OH)5.[1] It is an ordered 1:1 interstratification of cookeite and paragonite. It has perfect cleavage, a pearly luster and leaves a white streak. Its crystal structure is monoclinic, and it is a soft mineral with a hardness rated 2-3 on the Mohs scale.[1][2]
Saliotite was first described in 1994 for an occurrence in an outcrop of high grade schist north of Almeria, Andalusia, Spain. It was named for French geologist Pierre Saliot.[1]
References
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