Tenacity
Brittle
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
2.72-2.755.00-5.30
1
7.18
👆🏻
Fracture
Uneven
Uneven, ConchoidalWalter Schumann, Conchoidal
Cleavage
Perfect on [001], good on [010], imperfect on [110]
None, may show partings on {0001} and {10 1 1}
Mohs Hardness
6-6.56
2
10
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Chemical Composition
Ca(70-90%)Na(30-10%)(Al,Si)AlSi 2O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
Fe 2O 3Arthur Thomas , Gemstones (2009)