Tenacity
Brittle
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
2.652.72-2.75
1
7.18
👆🏻
Fracture
Conchoidal, ConchoidalWalter Schumann
Uneven
Cleavage
3,1
Perfect on [001], good on [010], imperfect on [110]
Mohs Hardness
76-6.5
2
10
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Chemical Composition
SiO 2Ulrich Henn and Claudio C.
Ca(70-90%)Na(30-10%)(Al,Si)AlSi 2O 8Michael OâDonoghue , Gems, Sixth Edition (2006)