Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
5.52.9-3.5
1
7.18
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Fracture
Conchoidal
Conchoidal
Cleavage
{111} Indistinct, {111} Indistinct, {111} Indistinct
{110} Perfect, {???} Distinct, {???} Distinct
Mohs Hardness
5-5.55.5-6
2
10
👆🏻
Chemical Composition
(Ca,Na) 2Ta 2O 6(O,OH,F)Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
(Mg,Fe2+ ) 2(Mg,Fe2+ ) 5Si 8O 22(OH) 2Anthony et al , Handbook of mineralogy (2001)