Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
Perfect on {001}, good on {210}, poor on {010}
SrSO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
From the Greek for oblique and fracture, descriptive of the cleavage
(Na,K)AlSi 3O 8Michael OâDonoghue , Gems, Sixth Edition (2006)