Leifite

General Information:
 Chemical Formula:
Na2(Si,Al,Be)7(O,OH,F)14
 Composition:
(Molecular Weight = 425.47 gm)
Sodium 10.81 % Na
Beryllium 1.48 % Be
Aluminum 13.32 % Al
Silicon 23.76 % Si
Hydrogen 0.76 % H 
Oxygen 43.62 % O 
Fluorine 6.25 % F 
 Empirical Formula:
Na2Si3.6Al2.1Be0.7O8.4(OH)3.2F1.4
 Environment:
Cavities in alkali-pegmatite veins.
 Locality:
Narsarsuk, Greenland.
Physical Properties:
 Cleavage:
[???] Good, [???] Good
 Color:
colorless or white.
 Density:
2.57
 Diaphaniety:
Transparent
 Habits:
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., Pseudo Hexagonal - Crystals show a hexagonal outline.,
 Hardness:
6 - Orthoclase
 Luster:
Vitreous (Glassy)
 Streak:
white
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