Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
3.76-3.773.03-3.18
1
7.18
👆🏻
Fracture
-
Uneven, Irregular, Conchoidal
Cleavage
{110} Perfect, {110} Perfect
{???} Indistinct
Mohs Hardness
5-67-7.5
2
10
👆🏻
Chemical Composition
(Fe,Mn) 7Si 7O 21Ulrich Henn and Claudio C.
Na(Mg 3)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012)