General Information:
Chemical Formula:
Fe++Fe+++4(PO4)4(OH)2·2(H2O)
Composition:
(Molecular Weight = 729.17 gm)
Iron 38.30 % Fe
Phosphorus 16.99 % P
Hydrogen 0.83 % H
Oxygen 43.88 % O
Empirical Formula:
Fe2+Fe3+4(PO4)4(OH)2·2(H2O)
Environment:
In a pegmatite.
Locality:
Sandamab, near Usakos, Namibia.
Name Origin:
Named by Paul Keller for his wife, Gini Keller.
Physical Properties:
Cleavage:
None
Color:
blackish brown, black, or blackish green.
Density:
3.41
Diaphaniety:
Translucent
Habits:
Crystalline - Fine - Occurs as well-formed fine sized crystals., ,
Hardness:
3-4 - Calcite-Fluorite
Luster:
Vitreous - Greasy
Streak:
olive green
More details...