Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
{100} perfect; {110} and {1 1 0} good; {010} poor
(Ca,Mn2+ )Si 3O 9Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Mn 3Al 2(SiO 4) 3Arthur Thomas , Gemstones (2009)