Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
Perfect [001] good [010] poor [110]
CaAl 2Si 2O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
Ca(Nd,Ce,La) 2(CO 3) 3F 2Ulrich Henn and Claudio C.