Tenacity
Brittle
Brittle
Solubility
Soluble
-
Durability
-
-
Specific Gravity
2.95-2.965.00-5.30
1
7.18
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Fracture
Conchoidal
Uneven, ConchoidalWalter Schumann, Conchoidal
Cleavage
None
None, may show partings on {0001} and {10 1 1}
Mohs Hardness
7-7.56
2
10
👆🏻
Chemical Composition
Mg 3B 7O 13ClMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Fe 2O 3Arthur Thomas , Gemstones (2009)