Blue Opal

An Exotic & Common Gem Material

- HELEN SERRAS-HERMAN

Blue opal is a gorgeous gem material that lapidaries use to create stunning artwork.

It is classified as a type of common opal — an opal that does not typically display the optical phenomenon of play of color over its base color. Its designation doesn't do it justice because blue opal is part of the family of “exotic common” opals, whose beauty is based on their striking body color and scenic patterns, not their play of color. Other members in this family are pink opal, yellow opal, morado opal, ice-cream opal, Tiffany stone, butterscotch opal, various green opals and white and dendritic opal.

WHAT IS COMMON OPAL?

In common opal, the body color is caused by impurities in the silicon dioxide (SiO2), in contrast to precious opal, where the spectral colors are the result of light reflecting and refracting through silica spheres in perfectly aligned in orderly rows, causing interference and diffraction.

The term “common opal” is an unfortunate one, and I, along with many other opal dealers and appraisers in the trade, believe that the term “exotic common opals” is more appropriate, giving the materials the quality validation they deserve.

Two distinct varieties of blue opal are found on the market: blue opal from Peru, which has an electric neon blue coloration, and blue opal from Arizona and Oregon, which matches the “aero blue” color.

There is another very recent find of blue opal fossil (petrified) wood with manganese dendritic inclusions and some native copper, from Indonesia’s West Java Province.

PERUVIAN ACARI COPPER MINES