Katophorite

General Information:
 Chemical Formula:
Na(CaNa)Fe++4(Al,Fe+++)Si7AlO22(OH)2
 Composition:
(Molecular Weight = 953.22 gm)
Sodium 4.82 % Na
Calcium 4.20 % Ca
Aluminum 4.95 % Al
Iron 24.90 % Fe
Silicon 20.62 % Si
Hydrogen 0.21 % H 
Oxygen 40.28 % O 
 Empirical Formula:
Na2CaFe2+4Al0.75Fe3+0.25Si7AlO22(OH)2
 Environment:
Found in basic alkaline igneous rocks.
 IMA Status:
Approved IMA 1997
 Locality:
La Tabatiere, PQ, Canada and the Christiania region, Norway.
 Name Origin:
Named from the Greek for "carrying down", in allusion to its volcanic origin.
Physical Properties:
 Cleavage:
[110] Perfect, [010] Parting
 Density:
3.2 - 3.5, Average = 3.35
 Diaphaniety:
Translucent
 Hardness:
5 - Apatite
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