Tenacity
Tough
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
3.20-3.262.90-2.98
1
7.18
👆🏻
Fracture
Splintery
Conchoidal, ConchoidalWalter Schumann
Cleavage
{010} perfect
Distinct on {11 2 0}, imperfect on {10 1 1}
Mohs Hardness
6-7.57.5-8
2
10
👆🏻
Chemical Composition
Al 2SiO 5Michael OâDonoghue , Gems, Sixth Edition (2006)
Be 2SiO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references