how to facet
gemstone main cabochon creation
min data

Mineral: opal
Gem: fire opal
Cut: 5 sided step cut
Origin: Mexico
General Info: The name is probably from the Latin "opalus", meaning "precious stone".
Additional Information
OK, here is where things get a bit strange. Precious opal has what is called "fire" in it, the streaks, or patches of color created by the ordering of the silica sphere to form a diffraction pattern.

"Fire opal" has no internal fire! It is transparent to translucent opal that is in the red to red-orange (or sometimes even yellow) color range.