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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