General Information:
Chemical Formula:
(Mn,Mg,Ca,Pb)9(As+++O3)(As+++++O4)2(OH)9·2(H2O) (?)
Physical Properties:
Cleavage:
[010] Indistinct
Color:
colorless, red, reddish brown, dark brown, or black.
Density:
3.57 - 3.79, Average = 3.68
Diaphaniety:
Transparent to Opaque
Hardness:
4.5 - Between Fluorite and Apatite
Luster:
Vitreous - Adamantine
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