Feature Gems & Gemology, Summer 2007, Volume 43, No. 2

Polymer-Impregnated Turquoise

A large “Persian” turquoise cabochon was impregnated with a material that was also present in cavities on its base. Raman spectroscopy identified the filler as a UV-hardened polymer. Although such polymers have been seen as fillers in other gems, especially emerald, this is the first time the GIA Laboratory has seen turquoise treated with this material.