Kankite

Kankite is a mineral with the chemical formula Fe3+AsO4·3.5(H2O).
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General Information:
 Chemical Formula:
Fe+++AsO4·3.5(H2O)
 Composition:
(Molecular Weight = 257.82 gm)
Iron 21.66 % Fe
Arsenic 29.06 % As
Hydrogen 2.74 % H 
Oxygen 46.54 % O 
 Empirical Formula:
Fe3+(AsO4)·3.5(H2O)
 Environment:
Found on the old (1200-1400) mine dumps.
 IMA Status:
Approved IMA 1976
 Locality:
Kank, Kutno Hora district, Stredocesky Kraj, Bohemia, Czech Republic.
 Name Origin:
Named for the locality.
Physical Properties:
 Color:
yellow green.
 Density:
2.7
 Habits:
Botryoidal - "Grape-like" rounded forms (e.g.. malachite)., Encrustations - Forms crust-like aggregates on matrix.,
 Hardness:
2-3 - Gypsum-Calcite
 Luster:
Vitreous - Dull
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