Difference between revisions of "Template:Emerald"

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| Optic nature || uniaxial -
 
| Optic nature || uniaxial -
 
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| Refraction index || 1.566 - 1.600
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| Refractive index || 1.566 - 1.600
 
|-  
 
|-  
 
| Birefringence || 0.004 - 0.010
 
| Birefringence || 0.004 - 0.010

Revision as of 11:41, 1 November 2006

Emerald
Chemical composition Beryllium Aluminium Silicate Be3Al2(SiO3)6
Crystal system Hexagonal
Habit prismatic
Cleavage imperfect, basal
Fracture conchoidal to uneven
Hardness 7.5 (brittle)
Optic nature uniaxial -
Refractive index 1.566 - 1.600
Birefringence 0.004 - 0.010
Dispersion low, 0.014
Specific gravity 2.67 - 2.78
Lustre Vitreous
Pleochroism weak to distinct