Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
3.18-3.375.5
1
7.18
👆🏻
Fracture
Conchoidal
Conchoidal
Cleavage
Perfect on 210
{111} Indistinct, {111} Indistinct, {111} Indistinct
Mohs Hardness
5.5-65-5.5
2
10
👆🏻
Chemical Composition
Na(Fe,Mg)7(AlSi7O22)(OH)2
(Ca,Na) 2Ta 2O 6(O,OH,F)Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references