Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
3.34-3.442.60-2.65
1
7.18
👆🏻
Fracture
Conchoidal
Uneven, Conchoidal
Cleavage
{111} Indistinct, {111} Indistinct, {111} Indistinct
Perfect on {001}, very good on {010}, imperfect on {110}
Mohs Hardness
8-8.56-6.5
2
10
👆🏻
Chemical Composition
(K,Cs)Al 4Be 4(B,Be) 12O 28Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
NaAlSi 3O 8Michael OâDonoghue , Gems, Sixth Edition (2006)