Diamonds • Precious Gemstones • Jewelry • Gemology

Is it real or .. ?

De Beers

As one might expect, De Beers is leading the charge in detecting and disclosure re synthetic diamonds. The cartel is spending tremendous sums to fund a new scientific division.

Their Gem Defensive Programme has as it's primary goal, the development of reliable methods to separate natural diamonds from these new synthetic diamonds. These reliable methods require sophisticated instruments that gem labs once only dreamed about. Now the De Beers Gem Defensive Programme is supplying DiamondSure and DiamondView instrumentation to large gemological labs at no cost.

The first screening is with DiamondSure, which projects light through a stone to analyze the refractive characteristics. If alarms sound, DiamondView is used. DiamondView uses ultraviolet light to reveal the diamond crystal's internal structure.

Newer instrumentation look for a suspected characteristic of synthetic diamonds. A luminescent band has been identified at 693.7 nanometers using a SAS2000 Raman photoluminescence spectroscope.

Marty Haske, president of Adamas Gemological Laboratories, Brookline, MA. is cautious, stating that the test is preliminary. "We have only studied a limited sample representing about three years of Russian near-colorless production. Out of a total of 37 diamonds we've studied, 27 showed the distinctive photoluminescence peak," he says.

"The existence of the feature is apparently correlated to short-wave fluorescence / phosphorescence present in the near-colorless synthetic diamond samples."

Research shows that when fluorescence or phosphorescence are detected, so is the spectroscopic peak.

But the Gemological Institute of America has not detected the feature. "The feature described is not present in the colorless synthetic samples we have observed and would need further investigation to determine its significance with regards to an identification criterion."

Note there is a suggestion that not even a Fourier transform infrared spectrometer can cetect a chemical vapor difussion grown synthetic diamond.

So what to do when confronted with the choice of buying a natural or synthetic diamond