Tenacity
-
-
Solubility
-
insoluble
Durability
-
-
Specific Gravity
3.76-3.776.46-6.57
1
7.18
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Fracture
-
Uneven, ConchoidalWalter Schumann, Conchoidal
Cleavage
{110} Perfect, {110} Perfect
Good [110] and [021]
Mohs Hardness
5-63-3.5
2
10
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Chemical Composition
(Fe,Mn) 7Si 7O 21Ulrich Henn and Claudio C.
PbCO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references