Difference between revisions of "Andesine"
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Revision as of 04:35, 9 January 2007
Andesine | |
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Chemical composition | (Na,Ca)[Al(Si,Al)Si2O8] |
Crystal system | Triclinic |
Habit | Prismatic |
Cleavage | Distinct to perfect |
Fracture | Conchoidal |
Hardness | 6.5 |
Optic nature | Biaxial +/- |
Refractive index | 1.551 - 1.560 |
Birefringence | 0.009 |
Specific gravity | 2.67 |
Lustre | Sub-vitreous |