Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
{110} Perfect, {110} Perfect, {110} Perfect
(Zn,Fe)SMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references
SiO2, Al2O3, FeO, MgO, CaO, K2O, Na2O