Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
3.03-3.184.76-5.03
1
7.18
👆🏻
Fracture
Uneven, Irregular, Conchoidal
Conchoidal
Cleavage
{???} Indistinct
None
Mohs Hardness
7-7.55.5-6.5
2
10
👆🏻
Chemical Composition
Na(Mg 3)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012)
(Mn2+ ,Fe2+ ,Mg)(Fe3+ ,Mn3+ ) 2O 4Anthony et al , Handbook of mineralogy (2001)