Tenacity
-
Brittle
Solubility
-
Soluble
Durability
-
-
Specific Gravity
3.03-3.183.30-3.50
1
7.18
👆🏻
Fracture
Uneven, Irregular, Conchoidal
Uneven, ConchoidalWalter Schumann, Conchoidal
Cleavage
{???} Indistinct
Perfect on {110}, poor on {101}, {001} rare
Mohs Hardness
7-7.55
2
10
👆🏻
Chemical Composition
Na(Mg 3)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012)
Zn 4Si 2O 7(OH) 2H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references