Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
2.45-2.585.00-5.30
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
3-3.56
2
10
👆🏻
Chemical Composition
Ca 2B 5SiO 9(OH) 5Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Fe 2O 3Arthur Thomas , Gemstones (2009)