Opal
From The Gemology Project
Revision as of 09:15, 28 September 2006 by Africanuck (talk | contribs)
Opal | |
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Chemical composition | SiO2+.H2O |
Crystal system | Amorphous |
Hardness | 5- 6 1/2 |
Refractive index | 1.45 (+.020;-0.080) |
Specific gravity | 2.15 (+0.07;-0.90) |
Lustre | Vitreous |
Phenomenom | Play of Color |