Difference between revisions of "Opal"

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[[Image:Precious_mexican_opal.jpg|left|framed|Precious Mexican Crystal Opal<br />Photo courtesy of<br />Rick Martin, Art Cut Gems]]<br clear="left" />
 
[[Image:Precious_mexican_opal.jpg|left|framed|Precious Mexican Crystal Opal<br />Photo courtesy of<br />Rick Martin, Art Cut Gems]]<br clear="left" />
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[[Image:YelOpal.jpg|left|framed|Yellow Common Opal<br />Photo courtesy of<br />Rick Martin, Art Cut Gems]]<br clear="left" />

Revision as of 06:29, 27 December 2006

Opal
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
Precious Mexican Crystal Opal
Photo courtesy of
Rick Martin, Art Cut Gems

Yellow Common Opal
Photo courtesy of
Rick Martin, Art Cut Gems