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Chemical composition Microcline feldspar
Crystal system Triclinic
Habit Massive
Hardness 6-6.5
Optic nature Biaxial -
Refractive index 1.522-1.530
Birefringence 0.008-0.010
Dispersion Low
Specific gravity 2.56
Lustre Vitreous
Microcline (aka Amazonite) with albite

Amazonite is a tradename for microcline (K-feldspar) and has a green to blue green colour.

Amazonite Cabochons

Microcline has the same chemical composition (KAlSi3O8) as orthoclase, but it grows as triclinic crystals opposed to the monoclinic orthoclase.