Treatments Under the Microscope

RAPAPORT…

Nomenclature for glass-filled ruby, disclosure codes for emerald treatments, radiation found in newly mined Chinese turquoise and a proposed fair trade/ethical mining certification model were among the hot topics discussed at the Gemstone Industry & Laboratory Conference (GILC) held in Tucson on February 5.

Organized by the International Colored Gemstone Association (ICA) and the American Gem Trade Association (AGTA), the conference drew representatives from laboratories worldwide, members of the CIBJO World Jewellery Confederation and the Laboratory Manual Harmonization Committee, both of which work to standardize gem nomenclature, as well as gem and jewelry wholesalers and retailers.

Ruby Angst

Although they’ve been on the market for many years, lead glass–treated ruby continues to plague the industry with concerns. A buyer-beware report that aired prior to Christmas on “Good Morning America” alleged that inexpensively priced glass-filled rubies were being sold at Macy’s without disclosure.

Gem trade watchdogs report that the levels of glass inside some of the stones, which are sometimes referred to as “composite” or “hybrid,” are getting so high they should not even be called “rubies.”

Christopher P. Smith, president of the New York City–based American Gemological Laboratory (AGL), told the GILC audience that the treatment takes poor-quality ruby rough through a multiple-step process of heating, acid cleaning and injection of a high-refractive index glass to make the material transparent, facet-grade. He said the stones are often so heavily treated that it’s not always possible to determine how much of them are ruby and how much are glass.

“In their natural state, these stones are translucent to opaque, with extensive cavities, channels and fractures that are in essence bonded together with tinted glass,” Smith explained, noting that the lead glass is susceptible to many solvents, including standard jewelry repair and household cleaning products. “Once the glass becomes etched, the apparent clarity of the stones is severely affected,” he cautioned.

At the conference, GILC formed a committee to develop an acceptable commercial name with proper disclosure language and clear care instructions to distinguish lead glass–treated rubies from regular heat-treated stones. The committee planned to present its recommendations to the CIBJO Congress in Munich, Germany.

“When properly disclosed, there is a place for this material in the market,” said Sushil Goyal, GILC chairman and owner of the New York–based Liberty Gems. Jack Abraham, a loose gem wholesaler and jewelry manufacturer also based in New York City, who specializes in ruby, emerald and sapphire, disagreed, lamenting that glass-filled ruby has been the worst thing for the business, because it threatens consumer confidence. Abraham emphasized the importance of buying and selling “natural” and “traditionally heated” ruby with a certificate from a reputable gem lab.

Another important discussion at the GILC centered on emerald treatments. According to Goyal, it was suggested that separate codes for oil and resin treatments be developed and a newly formed GILC committee was assigned to address all emerald issues.

Turquoise Under Scrutiny

Shane McClure of the Gemological Institute of America (GIA) discussed a new find of turquoise from China’s Hubei Province that contains radioactive uranium mineral as inclusions. McClure, in collaboration with John Koivula, also of GIA, wrote about the discovery in the Winter 2009 issue of Gems & Gemology.

McClure reported that several different clients submitted turquoise beads and cabochons to GIA’s lab that had unusual, prominent yellow inclusions, which were identified by Raman analysis as francevillite, a hydrated barium uranium vanadate. Because uranium is a major constituent in francevillite, GIA checked for radioactivity with a Geiger counter, and the stones registered low levels of radiation. Using a Victoreen 290 survey meter, researchers found most samples were only slightly above background radiation levels, such as are present in the daily environment, but a few reached 8 millirems/hour, which, although a high number, is still considered weak and generally harmless.

Another GILC committee was assigned to develop recommendations on importing this product in accordance with Nuclear Regulatory Commission (NRC) guidelines.  

Fair Play

Jean Claude Michelou, ICA vice president, pitched a proposal for certification of gemstone-producing countries, based on their poverty reduction, capacity building and value addition to the artisanal miners supply chain to the market. Unlike diamonds, 80 percent of gemstone mining is small scale, with 90 percent of these small-scale mines located in developing and emerging nations.

“Unlike gold, gemstones are not a commodity. Unlike with diamonds, there are no centralized marketing and market price controls. Gemstones are value-based on regional and seasonal marketing and branding strategies,” Michelou explained, noting there are “different countries, different cultures, different rules and regulations already in place for a host of different gemstones. But what is the same is the goal to have transparency in the supply chain from the source up, including legal, certified exports and initiatives that provide greater equity in the international trade.”

According to Michelou, the value of fair trade practices is in addressing the underlying causes of poverty through new forms of tradingrelationships. Rather than merely tackling the symptoms by checking standards compliance within individual operators and supply chains, he suggested the best way to make fair trade practices a reality in the gem trade is to bring countries into the fold.

Michelou believes that the world’s labs can play an important role in third-party verification in each country — i.e., certification at origin and of origin, disclosure of treatments, harmonization of certification principles and unification of standards related to ethical trade.

Referring to his current work in Nigeria as a country consultant as an example, Michelou said he is confident the same model can be adapted to any gem-producing country. He recommended CIBJO as the ideal organization to oversee such a “Jewelry Ethical Trade System” to which countries, not individual mines, would apply. 

The GILC plans to release a white paper detailing all the topics discussed at the February conference and Goyal said the group will soon launch a website that will include a forum for discussion of current and future topics of interest.