Kaatialaite

Kaatialaite (Fe(H2AsO4)3·5H2O) is a mineral found in Finland.
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General Information:
 Chemical Formula:
Fe+++[H2As+++++O4]3·5-5.5(H2O)
 Composition:
(Molecular Weight = 577.74 gm)
Iron 9.67 % Fe
Arsenic 38.90 % As
Hydrogen 2.97 % H 
Oxygen 48.46 % O 
 Empirical Formula:
Fe3+3(H2)3(AsO4)·5.5(H2O)
 Locality:
Kaatiala granite pegmatite, Kuortane, western Finland.
 Name Origin:
Named for the locality.
Physical Properties:
 Color:
greenish blue, gray, yellow, or white.
 Density:
2.64
 Diaphaniety:
Transparent
 Habits:
Acicular - Occurs as needle-like crystals., Lath - Shaped like a small, thin plaster lath, tabular (rectangular) in shape.,
 Streak:
white
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