Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
5.53.355-3.433
1
7.18
👆🏻
Fracture
Conchoidal
Uneven
Cleavage
{111} Indistinct, {111} Indistinct, {111} Indistinct
{???} Good, {???} Good
Mohs Hardness
5-5.5-9999
2
10
👆🏻
Chemical Composition
(Ca,Na) 2Ta 2O 6(O,OH,F)Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
(Ca,Mn2+ ,Fe2+ ) 3Al 2BSi 4O 15(OH)Anthony et al , Handbook of mineralogy (2001)