De Beers, GIA Race To Build Synthetic Diamond Detector

The diamond trade is meeting the threat of non-disclosure of gem-quality synthetics head-on.

By Russell Shor, senior editor -- JCK Online, 9/1/1995 2:00:00 AM

De Beers technicians are in a race against time to develop an easy-to-use, affordable device that can detect gem-quality synthetic diamonds before they reach the market in commercial quantities.

The De Beers research center in Maidenhead, England, has been working on the device for several years. It's also helping similar projects at the Gemological Institute of America and other labs by providing information and funding.

The work was announced at a recent Presidents' Meeting of the World Federation of Diamond Bourses in Johannesburg, South Africa. At the meeting, delegates discussed current and future problems affecting the industry.

Synthetic and treated diamonds are the greatest long-term threat to the industry, says Jacques Roisen, one of New York's leading diamond manufacturers, president of the International Diamond Manufacturers Association and a speaker at the meeting. "Ever increasing numbers of fracture-filled and other treated diamonds sold in the marketplace without disclosure will undermine the integrity and reputation of our industry and destroy an already weakened consumer confidence in diamonds," he says.

"The emergence of synthetic diamonds, if allowed to go unchecked, is certain to provide equally fertile soil for fraud and deception."

The best way to circumvent this threat of fraud and deception is the development of an affordable instrument that retailers and even consumers can use to detect treated or synthetic diamonds, he says.

"I beseech the world diamond organizations to join with De Beers and GIA to fund research to develop technology which can simply and easily identify the presence of treated, infused or synthetic diamonds at every level of the marketplace," he says.

Roisen says he's already made a $100,000 contribution to GIA for this purpose.

Priority project: The project to create a "little black box" to detect synthetic diamonds, even small goods in parcels and mounted into jewelry, has been a high priority at De Beers. A number of prototypes have been tested. "We've been doing extensive testing to develop a procedure that will ensure such instruments give correct readings and never falsely identify synthetics as naturals and vice versa," says Howard Vaughn, a De Beers' spokesman.

Other labs have been doing similar work, says Vaughn. For example, De Beers has shared information and allocated some funding to GIA for its work on developing such a device.

Dr. James Shigley, head of GIA research, says he's reasonably hopeful a device as cheap and easy to use as a pen-sized cubic zirconia thermal tester could be developed some day. But he cautions that the day isn't around the corner. He stresses that gemologists can already distinguish synthetic diamonds from naturals with proper equipment and training. But the challenge of creating a device that can do it cheaply, easily and accurately isn't easy.

"First we have to look at the problem from two angles: what unique characteristics distinguish synthetics from naturals and what properties are unique to naturals," he says. "Then we have to be certain these properties really are unique to either synthetics or naturals."

A number of differences can be measured:

Many synthetics have a unique ultraviolet fluorescence turning yellow-green under shortwave UV lights.
Some synthetics are magnetic.
Most natural diamonds are Type 1 A, which have unique absorption bands that can be seen by a spectroscope.
Only synthetics have metallic inclusions.

Cross checks: "The process of creating synthetic diamonds is very different from the way natural diamonds are created, so there's potentially a great variety of distinguishing characteristics," says Shigley.

But most researchers believe they will have to create an instrument that measures several characteristics to act as cross checks, perhaps using fluorescence first, then testing for another characteristic to ensure no naturals with unusual florescence are tagged as synthetic. Most synthetics have a distinctive yellowish green fluorescence, but there's a big variation within yellow stones and an even bigger variation within colorless material, says GIA researcher Emmanuel Fritsch.

The fluorescence test is appealing because it would lend itself well to screening large parcels. Much of the concern over synthetics centers on smaller diamonds because they are easier to create and much less likely to be checked by a gem lab.

But the need for a second or even third corroborative test poses a challenge. "I don't think there's a way to simplify the process to a needle that has a red zone for synthetics and a green zone for naturals," says Fritsch.

Despite the flurry of activity to create a synthetics detector, commercial quantities of man-made gem diamonds are still some years off, says Michael Grantham, market liaison for De Beers' marketing arm, the Central Selling Organisation.

General Electric and Sumitomo Electric produce potentially cuttable synthetic diamonds for industry, and several Russian groups are making such stones. Small quantities of yellowish synthetic diamonds from Russia reportedly have leaked into the trade. In fact, Tairus, a Russian-Thai venture, sold 30 synthetic diamonds to GIA at the JCK International Jewelry Show held in Las Vegas, Nev., in June. But GIA President William Boyajian says they were not part of a commercial line.

In addition, Chatham Created Gems of San Francisco, Cal., has announced it will market a line of colorless synthetic diamonds from Russia. But that effort remains plagued by production problems.

Continuing problems: Delegates at the meeting also debated two current problems facing the diamond trade: low profits and Russian diamond sales outside of the CSO.

WFDB President Eli Izhakoff says a warming in relations between De Beers and the head of the Russian State Committee on Precious Stones, Evgeny Bytchkov, that began at a meeting in Russia in June continued at the WFDB meeting. However, diamond dealers at the latter meeting remained concerned enough that they implored the Russians to cooperate with De Beers to maintain stability in the diamond market.

"The world diamond leadership has consistently demonstrated a willingness to put aside national interests and join together in partnership to confront every issue of common concern," says Roisen. "What has kept this business thriving and well is undoubtedly single-channel distribution through the CSO."

Bytchkov has said Russia wants to keep the diamond market stable, but also wants to maximize the return from its diamond resources through joint manufacturing ventures and local polishing operations.

On the continuing struggle against low profits, De Beers Vice Chairman Nicky Oppenheimer says that blaming the Russians and the CSO for the problem touches only the supply side. On the demand side, he says, pricing power has shifted to consumers because of intense price competition.

Izhakoff warns that continued low profits are sapping confidence in the industry among banks and causing many dealers to shift capital out of the industry into more lucrative ventures.