Carlsbad, California – The Gemological Institute of America has cut off four clients traced to hundreds of diamonds submitted with an undisclosed treatment that improves their color by as much as three grades but fades over time.
The approximately 500 diamonds passed through the GIA’s laboratory in Ramat Gan, Israel in the past several months and now are circulating in the trade. The GIA sent out notifications about the still-unidentified temporary treatment Tuesday and is asking anyone in the trade with these 424 potentially treated stones to turn them back into the GIA for reexamination. (Approximately 76 of the 500 already have been reexamined by the GIA.)
The vast majority of the stones are 1 carat or larger, with a number of 3-, 4- and even 5-carat stones in the mix. A three color-grade jump for stones of this size would amount to a big difference in price or, as one industry player observed, “big bucks” for the sellers.
