Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
-99992.55-2.65
1
7.18
👆🏻
Fracture
Conchoidal
Conchoidal
Cleavage
None
Perfect {10 1 0}
Mohs Hardness
7-7.55.5-6
2
10
👆🏻
Chemical Composition
Al 4(Ta,Nb) 3(O,OH,F) 14Ulrich Henn and Claudio C.
(Na,Ca,K) 8(Si,Al) 12O 24(SO 4,Cl,CO 3) 3(H 2O)Arthur Thomas , Gemstones (2009)