General Information:
Chemical Formula:
NaxMgxAl2-x(F,OH)6·(H2O)
Environment:
Alteration product of cryolite.
Locality:
Ivigtut, Greenland.
Physical Properties:
Cleavage:
[???] Perfect, [???] Perfect, [???] Perfect
Color:
colorless or white.
Density:
2.55
Diaphaniety:
Transparent to translucent
Hardness:
4.5 - Between Fluorite and Apatite
Luminescence:
Non-fluorescent.
Luster:
Vitreous - Greasy
Streak:
white
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