Tenacity
-
Brittle
Solubility
-
insoluble
Durability
-
-
Specific Gravity
3.03-3.186.86-7.03
1
7.18
👆🏻
Fracture
Uneven, Irregular, Conchoidal
Subconchoidal, Uneven, Conchoidal, Irregular
Cleavage
{???} Indistinct
{100} imperfect, {110} indistinct; partings on {111} or {011}
Mohs Hardness
7-7.56-7
2
10
👆🏻
Chemical Composition
Na(Mg 3)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012)
SnO 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references