Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
3.18-3.375.00-5.30
1
7.18
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Fracture
Conchoidal
Uneven, ConchoidalWalter Schumann, Conchoidal
Cleavage
Perfect on 210
None, may show partings on {0001} and {10 1 1}
Mohs Hardness
5.5-66
2
10
👆🏻
Chemical Composition
Na(Fe,Mg)7(AlSi7O22)(OH)2
Fe 2O 3Arthur Thomas , Gemstones (2009)