Tenacity
Brittle
Tough
Solubility
-
-
Durability
-
-
Specific Gravity
2.90-2.983.20-3.26
1
7.18
👆🏻
Fracture
Conchoidal, ConchoidalWalter Schumann
Splintery
Cleavage
Distinct on {11 2 0}, imperfect on {10 1 1}
{010} perfect
Mohs Hardness
7.5-86-7.5
2
10
👆🏻
Chemical Composition
Be 2SiO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Al 2SiO 5Michael OâDonoghue , Gems, Sixth Edition (2006)