Difference between revisions of "Amazonite"
From The Gemology Project
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[[image:Amazonite_xls.jpg|left|thumb|400px|Microcline (aka Amazonite) with albite]] | [[image:Amazonite_xls.jpg|left|thumb|400px|Microcline (aka Amazonite) with albite]] | ||
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− | Amazonite is a tradename for [[microcline]] ([[feldspar|K-feldspar]]) and has a green to blue green colour. | + | Amazonite is a tradename for [[microcline]] ([[feldspar|K-feldspar]]) and has a green to blue green colour.<br /> |
− | + | [[image:Amazonite_cabs.jpg|Amazonite Cabochons]] | |
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Microcline has the same chemical composition (KAlSi<sub>3</sub>O<sub>8</sub>) as [[orthoclase]], but it grows as triclinic crystals opposed to the monoclinic orthoclase. | Microcline has the same chemical composition (KAlSi<sub>3</sub>O<sub>8</sub>) as [[orthoclase]], but it grows as triclinic crystals opposed to the monoclinic orthoclase. | ||
Revision as of 03:30, 27 September 2010
Amazonite | |
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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 |
Amazonite is a tradename for microcline (K-feldspar) and has a green to blue green colour.
Microcline has the same chemical composition (KAlSi3O8) as orthoclase, but it grows as triclinic crystals opposed to the monoclinic orthoclase.
Sources
- Gems Their Sources, Descriptions and Identification 4th Edition (1990) - Robert Webster (6th ed.)
- Gemstones of the world, 3rd rev and exp edition (2006) - Walter Schuman ISBN 1402740166