Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
2.30-2.605.00-5.30
1
7.18
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Fracture
Uneven, Conchoidal
Uneven, ConchoidalWalter Schumann, Conchoidal
Cleavage
{111} Imperfect
None, may show partings on {0001} and {10 1 1}
Mohs Hardness
5.5-66
2
10
👆🏻
Chemical Composition
Na 4AlBeSi 4O 12ClMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Fe 2O 3Arthur Thomas , Gemstones (2009)