Yukonite

General Information:
 Chemical Formula:
Ca7Fe+++11(AsO4)9O10·24.3(H2O)
 Composition:
(Molecular Weight = 2,742.90 gm)
Calcium 10.23 % Ca
Iron 22.40 % Fe
Arsenic 24.58 % As
Hydrogen 1.79 % H 
Oxygen 41.01 % O 
 Empirical Formula:
Ca7Fe3+11(AsO4)9O10·24.3(H2O)
 Locality:
Tagish Lake, Yukon Territory, Canada.
 Name Origin:
Named for the locality.
Physical Properties:
 Color:
brownish black, dark red, or reddish brown.
 Density:
2.8
 Habits:
Amorphous - No crystalline form or imitative shape., ,
 Hardness:
2-3 - Gypsum-Calcite
 Luminescence:
Non-fluorescent.
 Luster:
Resinous
 Streak:
light brown
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