Alluaivite

General Information:
 Chemical Formula:
Na19(Ca,Mn++)6(Ti,Nb)3(Si3O9)2(Si10O28)2Cl·2(H2O)
 Composition:
(Molecular Weight = 2,169.25 gm)
Sodium 20.14 % Na
Calcium 8.31 % Ca
Titanium 4.97 % Ti
Manganese 3.80 % Mn
Niobium 3.21 % Nb
Silicon 20.72 % Si
Hydrogen 0.19 % H 
Chlorine 3.27 % Cl
Oxygen 35.40 % O 
 Empirical Formula:
Na19Ca4.5Mn2+1.5Ti2.25Nb0.75Si16O46Cl2·2(H2O)
 IMA Status:
Approved IMA 1989
Physical Properties:
 Cleavage:
None
 Color:
brownish pink or colorless.
 Density:
2.76
 Diaphaniety:
Transparent
 Hardness:
5-6 - Between Apatite and Orthoclase
 Luster:
Vitreous (Glassy)
 Streak:
white
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