1 Physical Properties
1.1 Tenacity
1.2 Solubility
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001)
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), (e.g. graphite).
1.6 Cleavage
2,1 basal ; 2,1 prismatic ; 3,1 pinacoidal
Distinct on {001} and {110}, indistinct on {100}
1.7 Mohs Hardness
1.8 Chemical Composition
Plagioclase Feldspar s: (Na,Ca)Al1-2Si3-2O8 Orthoclase Feldspar : KAlSi3O8
Pb 2(CO 3)Cl 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references