Akatoreite

Akatoreite ((Mn2+,Fe2+)9Al2[(OH)3|HSi4O13]) is a mineral found in New Zealand.
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General Information:
 Chemical Formula:
(Mn++,Fe++)Al2Si8O24(OH)8
 Composition:
(Molecular Weight = 853.86 gm)
Manganese 4.83 % Mn
Aluminum 6.32 % Al
Iron 1.64 % Fe
Silicon 26.31 % Si
Hydrogen 0.94 % H 
Oxygen 59.96 % O 
 Empirical Formula:
Mn3+0.75Fe3+0.25Al2Si8O24(OH)8
 IMA Status:
Approved IMA 1969
 Locality:
TL: New Zealand, Akatore creek, South Island
Physical Properties:
 Cleavage:
[010] Perfect
 Color:
orange or brown.
 Density:
3.48
 Diaphaniety:
Transparent
 Hardness:
6 - Orthoclase
 Luster:
Vitreous (Glassy)
 Streak:
yellow white
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