Wardite

Wardite is a hydrous sodium aluminium phosphate hydroxide mineral with formula: NaAl3(PO4)2(OH)4·2(H2O). Wardite is of interest for its rare crystallography. It crystallizes in the tetragonal trapezohedral class and is one of only a few minerals in that class. Wardite forms vitreous green to bluish green to white to colorless crystals, masses, and fibrous encrustations. It has a Mohs hardness of 5 and a specific gravity of 2.81 - 2.87. It occurs with variscite in nodules and occurs in pegmatites and phosphate deposits through alteration of amblygonite.
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General Information:
 Chemical Formula:
NaAl3(PO4)2(OH)4·2(H2O)
 Composition:
(Molecular Weight = 397.94 gm)
Sodium 5.78 % Na
Aluminum 20.34 % Al
Phosphorus 15.57 % P 
Hydrogen 2.03 % H 
Oxygen 56.29 % O 
 Empirical Formula:
NaAl3(PO4)2(OH)4·2(H2O)
Physical Properties:
 Cleavage:
[???] Perfect
 Color:
blue green, colorless, white, or light green.
 Density:
2.81
 Diaphaniety:
Transparent to Translucent
 Habits:
Encrustations - Forms crust-like aggregates on matrix., ,
 Hardness:
5 - Apatite
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous (Glassy)
 Streak:
white
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