how to facet
gemstone main cabochon creation
min data

Mineral: opal
Gem: precious opal
Cut: pear cabochon
Origin: Australia
General Info: The name is probably from the Latin "opalus", meaning "precious stone".
Additional Information
Below are two micro images taken of a broad color flash area in the stone. The color in opal is caused by the orderly array of silica spheres which diffract the light and break it into its spectral hues. Since the "fire" (light play) is a physical phenomena, it changes when the stone is rotated or moved and the color appears to move around or throughout the gem.