Bayldonite

General Information:
 Chemical Formula:
(Cu,Zn)3Pb(AsO4)2(OH)2
 Composition:
(Molecular Weight = 727.71 gm)
Copper 26.20 % Cu
Arsenic 20.59 % As
Hydrogen 0.55 % H 
Lead 28.47 % Pb
Oxygen 24.18 % O 
 Empirical Formula:
PbCu3(AsO4)2(OH)2·(H2O)
 Name Origin:
Named after J. Bayldon.
Physical Properties:
 Cleavage:
None
 Color:
grass green, yellow green, or dark green.
 Density:
4.35 - 5.5, Average = 4.92
 Diaphaniety:
Subtranslucent
 Habits:
Encrustations - Forms crust-like aggregates on matrix., Mammillary - Larger "breast-like" rounded forms resembling botryoidal (e.g. malachite)., Druse - Crystal growth in a cavity whi ch results in numerous crystal tipped su
 Hardness:
4-5 - Fluorite-Apatite
 Luster:
Greasy (Oily)
 Streak:
green
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