Ahlfeldite

Ahlfeldite ((Ni,Co)[SeO3]·2H2O) is a mineral found in Bolivia.
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General Information:
 Chemical Formula:
(Ni,Co)SeO3·2(H2O)
 Composition:
(Molecular Weight = 221.74 gm)
Cobalt 6.64 % Co
Nickel 19.85 % Ni
Hydrogen 1.82 % H 
Selenium 35.61 % Se
Oxygen 36.08 % O 
 Empirical Formula:
Ni0.75Co0.25(SeO3)·2(H2O)
 Locality:
TL: Bolivia, Potos¡, Colquechaca
Physical Properties:
 Cleavage:
[110] Distinct, [103] Distinct
 Color:
pink brown, apple green, or red.
 Density:
3.37
 Diaphaniety:
Transparent
 Hardness:
2-2.5 - Gypsum-Finger Nail
 Luster:
Vitreous (Glassy)
 Streak:
light green
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