1 Physical Properties
1.1 Tenacity
1.2 Solubility
Gelatinises in acids
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Uneven, Conchoidal, Brittle
Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001)
1.6 Cleavage
Distinct on {110}
2,1 basal ; 2,1 prismatic ; 3,1 pinacoidal
1.7 Mohs Hardness
1.8 Chemical Composition
(Na,Ca)4-8Al6Si6(O,S)24(SO4,Cl)1-2
Plagioclase Feldspar s: (Na,Ca)Al1-2Si3-2O8 Orthoclase Feldspar : KAlSi3O8