Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
Uneven, ConchoidalWalter Schumann, Conchoidal
None, may show partings on {0001} and {10 1 1}
Fe 2O 3Arthur Thomas , Gemstones (2009)
Perfect [001] good [010] poor [110]
CaAl 2Si 2O 8Michael OâDonoghue , Gems, Sixth Edition (2006)