Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
From the Greek for oblique and fracture, descriptive of the cleavage
(Na,K)AlSi 3O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
Subconchoidal, Uneven, Conchoidal
Mn2+ Al(PO 4)(OH) 2H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)