Feature
Gems & Gemology, Winter 2011, Volume 47, No. 4
Dyed Purple Hydrophane Opal
Nathan Renfro and Shane F. McClure
Opals with an unusual purple bodycolor and strong play-of-color have recently appeared in the market. Reportedly from a new deposit in Mexico, they have a vivid bodycolor unlike that of any natural play-of-color opal seen in the trade so far. This alone was enough to raise suspicion, and gemological and spectroscopic evidence indicates that the purple coloration is artificial. A comparison of this purple opal with numerous samples from Ethiopia’s Wollo Province strongly suggests that it is actually dyed hydrophane opal from those deposits. Several previously undocumented characteristics of Wollo opals are described, including zeolite mineral inclusions.