Paraumbite

General Information:
 Chemical Formula:
K3Zr2HSi6O18·n(H2O) n=3 to 7
 Composition:
(Molecular Weight = 811.30 gm)
Potassium 14.46 % K 
Zirconium 22.49 % Zr
Silicon 20.77 % Si
Hydrogen 0.87 % H 
Oxygen 41.41 % O 
 Empirical Formula:
K3Zr2HSi6O18·3(H2O)
 Environment:
Alkalic pegmatites.
 Locality:
Mt. Eveslogchorr, eastern Khibiny massif, Kola Peninsula, Russia.
 Name Origin:
Named for the close structural similarity to umbite.
Physical Properties:
 Cleavage:
[010] Perfect, [100] Good
 Color:
colorless, white, or light yellow.
 Density:
2.59
 Diaphaniety:
Transparent to Translucent
 Habits:
Pseudo Hexagonal - Crystals show a hexagonal outline., ,
 Hardness:
4.5 - Between Fluorite and Apatite
 Luster:
Vitreous - Pearly
 Streak:
white
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