General Information:
Chemical Formula:
PbFe+++3(AsO4)(SO4)(OH)6
Composition:
(Molecular Weight = 711.77 gm)
Iron 23.54 % Fe
Arsenic 10.53 % As
Hydrogen 0.85 % H
Lead 29.11 % Pb
Sulfur 4.51 % S
Oxygen 31.47 % O
Empirical Formula:
PbFe3+3(AsO4)(SO4)(OH)6
Name Origin:
Named after the French mineralogist, F. S. Beudant (1787-1850).
Physical Properties:
Cleavage:
[0001] Perfect
Color:
brown, green, yellow, dark green, or orange.
Density:
4.1 - 4.3, Average = 4.19
Diaphaniety:
Transparent to Translucent
Habits:
Blocky - Rhombohedral - Crystal shape resembles rhomohedrons., Druse - Crystal growth in a cavity which results in numerous crystal tipped surfaces., Platy - Sheet forms (e.g. micas).
Hardness:
4 - Fluorite
Luminescence:
None.
Luster:
Adamantine
Streak:
greenish yellow
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