Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
2.90-2.983.19-3.56
1
7.18
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Fracture
Conchoidal, ConchoidalWalter Schumann
Uneven, Conchoidal
Cleavage
Distinct on {11 2 0}, imperfect on {10 1 1}
{110} Perfect, {010} Indistinct
Mohs Hardness
7.5-85.5-6
2
10
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Chemical Composition
Be 2SiO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
(Ca,Na)(Mg,Fe,Al,Ti)(Si,Al) 2O 6Anthony et al , Handbook of mineralogy (2001)