Jeffreyite

General Information:
 Chemical Formula:
(Ca,Na)2(Be,Al)Si2(O,OH)7
 Composition:
(Molecular Weight = 255.30 gm)
Sodium 4.50 % Na
Calcium 23.55 % Ca
Beryllium 2.65 % Be
Aluminum 2.64 % Al
Silicon 22.00 % Si
Hydrogen 0.79 % H 
Oxygen 43.87 % O 
 Empirical Formula:
Ca1.5Na0.5Be0.75Al0.25Si2O5(OH)2
 IMA Status:
Approved IMA 1983
Physical Properties:
 Cleavage:
[001] Perfect, [110] Perfect
 Color:
colorless.
 Density:
2.99
 Diaphaniety:
Transparent
 Hardness:
5 - Apatite
 Luster:
Vitreous (Glassy)
 Streak:
white
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