Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
2.90-3.145.5
1
7.18
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Fracture
Conchoidal, Uneven
Conchoidal
Cleavage
Imperfect; basal
{111} Indistinct, {111} Indistinct, {111} Indistinct
Mohs Hardness
7.5-85-5.5
2
10
👆🏻
Chemical Composition
(Be,Cs) 3Al 2Si 6O 18 · 0.5H 2OUlrich Henn and Claudio C.
(Ca,Na) 2Ta 2O 6(O,OH,F)Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references