Ilimaussite-(Ce)

General Information:
 Chemical Formula:
Ba2Na4CeFe+++Nb2Si8O28·5(H2O)
 Composition:
(Molecular Weight = 1,511.13 gm)
Barium 18.18 % Ba
Sodium 6.09 % Na
Cerium 9.27 % Ce
Niobium 12.30 % Nb
Iron 3.70 % Fe
Silicon 14.87 % Si
Hydrogen 0.67 % H 
Oxygen 34.94 % O 
 Empirical Formula:
Ba2Na4CeFe3+Nb2Si8O28·5(H2O)
 IMA Status:
Approved IMA 1987
Physical Properties:
 Color:
brownish yellow or yellowish white.
 Density:
3.6
 Diaphaniety:
Transparent to Subtranslucent
 Hardness:
4 - Fluorite
 Luster:
Earthy (Dull)
 Streak:
white
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