Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
3.69-3.813.03-3.18
1
7.18
👆🏻
Fracture
Uneven, Conchoidal to uneven, ConchoidalWalter Schumann
Uneven, Irregular, Conchoidal
Cleavage
Distinct on {110}, imperfect on {010}, poor on {001}
{???} Indistinct
Mohs Hardness
8.57-7.5
2
10
👆🏻
Chemical Composition
BeAl 2 O 4
Na(Mg 3)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012)