Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
2.85-3.005.5
1
7.18
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Fracture
Uneven
Conchoidal
Cleavage
Perfect
{111} Indistinct, {111} Indistinct, {111} Indistinct
Mohs Hardness
7.55-5.5
2
10
👆🏻
Chemical Composition
(Mg,Fe)Al 3(BO 4)(SiO 4)OUlrich Henn and Claudio C.
(Ca,Na) 2Ta 2O 6(O,OH,F)Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references