Tenacity
Brittle
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
3.69-3.812.20-2.26
1
7.18
👆🏻
Fracture
Uneven, Conchoidal to uneven, ConchoidalWalter Schumann
Uneven
Cleavage
Distinct on {110}, imperfect on {010}, poor on {001}
Perfect on {110}
Mohs Hardness
8.55-5.5
2
10
👆🏻
Chemical Composition
BeAl 2 O 4
Na 2[Al 2Si 3O 10] · 2H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references