Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
{110} Perfect, {010} Indistinct
(Ca,Na)(Mg,Fe,Al,Ti)(Si,Al) 2O 6Anthony et al , Handbook of mineralogy (2001)
On {10 1 0}, perfect; parting on {000 1 }
(Zn,Mn2+ )OMichael OâDonoghue , Gems, Sixth Edition (2006)