General Information:
Chemical Formula:
Al4(PO4)3(OH)3·9(H2O)
Composition:
(Molecular Weight = 606.00 gm)
Aluminum 17.81 % Al
Phosphorus 15.33 % P
Hydrogen 3.49 % H
Oxygen 63.36 % O
Empirical Formula:
Al4(PO4)3(OH)3·9(H2O)
Environment:
On the dumps of a quartzite quarry.
IMA Status:
Approved IMA 1986
Locality:
Stavelot massif, Bihain, Belgium.
Name Origin:
Named for Rene Van Tassel (1916-), mineralogist of phosphate and sulfate minerals.
Physical Properties:
Cleavage:
[001] Good
Color:
pearl white.
Density:
2.3
Diaphaniety:
Transparent to Translucent
Habits:
Rosette - Bundled tabular aggregates resembling rose flower petals., ,
Hardness:
2-2.5 - Gypsum-Finger Nail
Luster:
Greasy (Oily)
Streak:
white
More details...