Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
Uneven, ConchoidalWalter Schumann
2,1 basal ; 2,1 prismatic ; 3,1 pinacoidal
Plagioclase Feldspar s: (Na,Ca)Al1-2Si3-2O8 Orthoclase Feldspar : KAlSi3O8
Subconchoidal, Conchoidal
Distinct on {010}, imperfect {110} and {011}
CaCO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references