Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
Perfect on {001}, very good on {010}, imperfect on {110}
NaAlSi 3O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
On {10 1 0}, perfect; parting on {000 1 }
(Zn,Mn2+ )OMichael OâDonoghue , Gems, Sixth Edition (2006)