SYNTHETIC DETECTION CHEAT SHEET
Following these simple steps could save your operation
More than a decade has passed since the production of the synthetic Sumitomo
diamond. Other labs - including three in Russia - as well as De Beers Industrial
Diamond Divisions, General Electric Co. and others have produced synthetic
diamonds commercially for industrial use. Yet relatively few synthetic diamonds
have been reported in the gem trade. Though that may soon change (see "Growing Carats," p.47), the delay has
given the gem trade a head start in nailing down synthetic diamond detection
Photo by Robert Weldon
When buying diamonds for your store, be confident about the goods. Obviously,
buying from a known and reputable source is crucial, but always be on the
lookout for synthetic diamonds and diamond treatments. Even De Beers views
synthetic diamonds as threatening enough to have designed two instruments
for quick and easy identification.
The sophisticated DiamondSure and DiamondView detectors measure complex
diamond spectrums and fluorescence and luminescence patterns and are now
in use at the Gemological Institute of America.
Unfortunately, these instruments are not yet available to those in the
trenches - retailers and diamond merchants. Gemologists have gotten used
to looking for treatments such as laser and/or fracture filling, but due
to the relative scarcity of synthetics in the trade, complacence and inattention
could cost dearly. Educating yourself and key employees is a must.
Publications such as the Gemological Institute of America's Gems &
Gemology provide continual updates on the progress and detection of
diamond synthetics. We'll give you the "Cliffs Notes" version
of what to look for.
In short-wave lighting units, weak to strong green fluorescence may be
seen in synthetic yellow diamonds, but not always. Synthetic diamonds are
generally inert under long-wave fluorescence. The greenish color is rarely
seen in natural yellow diamonds, so green fluorescence indicates a strong
suspicion of synthetic. Colorless synthetics may sometimes exhibit greenish,
yellow or orange fluorescence, but if the stone fluoresces other colors,
more tests need to be performed.
If the diamond has greenish phosphorescence or emits light away from
short-wave lighting, the stone may be synthetic. Natural stones rarely phosphoresce
and then only weakly to moderately, and the phosphorescence does not last
long. Colorless diamonds always phosphoresce a long-lasting weak to strong
Synthetic diamonds are often attracted to strong magnets due to the metallic
flux inclusions. Natural diamonds are never attracted to magnets.
Always examine a diamond under a microscope. If you see metallic reflections,
especially if they're opaque to transmitted light, suspect the stone is
Metallic inclusions do not occur in diamonds, though inclusions of transparent
or colorful minerals, such as garnet, often do occur in natural diamonds.
In natural diamonds, these inclusions are often accompanied by "stress
fractures" (or minute internal fractures associated with the inclusion)
which are not present in synthetics.
Size & Color
For the time being gem labs report seeing only small brownish yellow
or yellow stones in the 0.10- to 0.25-ct. range coming in for identification.
But containing your suspicions to this size and color category may not be
Synthetics are getting larger, more are entering the trade and high-tech
synthesis is becoming capable of producing man-made diamonds in various
colors. You may never be completely sure about the results of your own examinations.
If doubts persist, send the stone to a reputable laboratory for confirmation.
- by Robert Weldon, G.G.
Copyright © 1998 by Bond Communications.