Difference between revisions of "Template:Heliodor"
From The Gemology Project
Africanuck (talk | contribs) |
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| Optic nature || uniaxial - | | Optic nature || uniaxial - | ||
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− | | | + | | 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) |