Difference between revisions of "Template:Heliodor"

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| Optic nature || uniaxial -
 
| Optic nature || uniaxial -
 
|-
 
|-
| Refraction index || 1.57 - 1.58
+
| Refractive index || 1.57 - 1.58
 
|-  
 
|-  
 
| Birefringence || 0.004 - 0.009
 
| Birefringence || 0.004 - 0.009

Revision as of 11:44, 1 November 2006

Heliodor
Chemical composition Beryllium Aluminium Silicate Be3Al2(SiO3)6
Crystal system Hexagonal
Habit prismatice
Cleavage poor, basal
Fracture conchoidal to uneven
Hardness 7.5
Optic nature uniaxial -
Refractive index 1.57 - 1.58
Birefringence 0.004 - 0.009
Dispersion low, 0.014
Specific gravity 2.7 - 2.9
Lustre Vitreous
Pleochroism weak to moderate (shades of body color)