Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
3.69-3.812.60-2.64
1
7.18
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Fracture
Uneven, Conchoidal to uneven, ConchoidalWalter Schumann
Uneven, Splintery, Conchoidal
Cleavage
Distinct on {110}, imperfect on {010}, poor on {001}
Absent
Mohs Hardness
8.56.5-7
2
10
👆🏻
Chemical Composition
BeAl 2 O 4
SiO 2Arthur Thomas , Gemstones (2009)