General Information:
Chemical Formula:
PbAl3(AsO4)2(OH)5·(H2O)
Composition:
(Molecular Weight = 669.04 gm)
Aluminum 12.10 % Al
Arsenic 22.40 % As
Hydrogen 1.05 % H
Lead 30.97 % Pb
Oxygen 33.48 % O
Empirical Formula:
PbAl3(AsO4)2(OH)5·(H2O)
Environment:
Associated with crocoite.
IMA Status:
Approved IMA 1982
Locality:
Dundas district, TAS, Australia.
Name Origin:
Named for Helut von Philipsborn (1892-1983), Mineralogist, University of Bonn, Germany.
Physical Properties:
Cleavage:
None
Color:
colorless or gray green.
Density:
4.33
Diaphaniety:
Transparent
Habits:
Massive - Uniformly indistinguishable crystals forming large masses., Earthy - Dull, clay-like texture with no visible crystalline affinities, (e.g. howlite).,
Hardness:
4.5 - Between Fluorite and Apatite
Luster:
Vitreous (Glassy)
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