Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
2.77-2.882.90-2.98
1
7.18
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Fracture
Uneven
Conchoidal, ConchoidalWalter Schumann
Cleavage
Perfect basal
Distinct on {11 2 0}, imperfect on {10 1 1}
Mohs Hardness
2.57.5-8
2
10
👆🏻
Chemical Composition
K(Al,Cr) 3Si 3O 10(OH) 2Gemdat.org , Management Team (2012)
Be 2SiO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references