Taranakite

General Information:
 Chemical Formula:
K3Al5(HPO4)6(PO4)2·18(H2O)
 Composition:
(Molecular Weight = 1,342.30 gm)
Potassium 8.74 % K 
Aluminum 10.05 % Al
Phosphorus 18.46 % P 
Hydrogen 3.15 % H 
Oxygen 59.60 % O 
 Empirical Formula:
K3Al5(HPO4)6(PO4)2·18(H2O)
Physical Properties:
 Color:
gray white, yellowish white, or white.
 Density:
2.09
 Hardness:
1-2 - Between Talc and Gypsum
 Luminescence:
Fluorescent.
 Streak:
white
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