Diamonds require specific conditions over long periods of time to grow in the earth. The politics of mining diamonds concerns many consumers around the world. Over the past decade, high quality, laboratory-grown diamonds--identical to natural diamonds in physical, optical and chemical properties--have found their way into the trade and jewelry stores.
Identifying the man-made material requires sophisticated tests. Gemological Institute of America defines the stones as "synthetic." The European Gemological Laboratory grades synthetics' color.
Differentiating natural and synthetic diamonds requires gemological evaluation. In 2010, synthetic diamonds are the hardest gemstones on earth. A natural diamond, rated 10 for superior hardness on the Moh's scale, was once considered the hardest material on earth. Because synthetics grow quickly in highly compressed conditions, single crystals may grow in one direction. Many natural diamonds form from multiple crystals, creating the potential for fracture between crystals.
Determining the origin of your diamond also requires professional lab testing. According to the European Gemological Laboratory, a professional gem laboratory evaluates gemstones for origin by investigating their natural inclusions. Minute inclusions present in even the finest gemstones help the gemologist identify where the stone was mined. Similarly, professionals know how to identify in what lab the stones were grown.
According to James Shigley of the Gemological Institute of America in California, as quoted in Science News in May 2010, the water present in natural gems' inclusions is one way to tell the stone came from the earth. Inclusions of lab-created diamonds have no water in them.
Other identifiers of synthetic gemstones include minute metal traces in the gemstone, such as platinum or boron.
Owning ultra-rare colored natural diamonds is the domain of the super-wealthy, but laboratory work has put synthetic colored gems within reach of most people.
According to Gemesis Corporation, one of the top providers of synthetic diamonds, astounding suites of matched colored diamond jewelry is now possible. Colored gem-quality diamonds occur with more frequency in the laboratory, in all colors of the rainbow. Most colored diamonds occur in prized canary yellow and orange hues.
Unlike natural diamonds, clear colorless synthetic diamonds occur with less frequency than colored synthetics.
Selecting a D-Flawless diamond mined from the earth is prohibitively expensive for most people. According to the Gemological Institute of America, "D" color describes colorless diamonds. "Flawless" or "Internally Flawless" describes the lack of inclusions detected in the diamond.
EGL grades synthetic diamonds for color. Comparing a prized colorless synthetic diamond against its natural counterpart for price and the "4 C's"--color, cut, clarity and carat weight--is possible with this certification.
In GIA's lab, synthetic diamonds are identified only as "synthetic" along with the gemstone's dimensions.
Fluorescence of a synthetic diamond differentiates it from a natural gemstone. Gemologists use a spectrascope to evaluate synthetic diamonds in ultraviolet and infrared light. They also use X-rays to evaluate these gemstones.
DeBeers Corporation sells the DiamondView tester. The cubo-octahedral form of synthetics' crystal growth distinguishes them from natural diamond crystals' octahedral pattern. According to DeBeers, ultraviolet fluorescence enables gemologists to determine telltale nickel, nitrogen and other metals in synthetic diamonds.
- GIA: 4 C's of diamonds
- "Gems"; M. O'Donoghue; 2006
- "High Pressure-High Temperature Growth of Diamond Crystals"; Diam. Rel. Mater; 2005
- "Recent Progress and Perspectives in Single-Digit Nanodiamond"; O. Osawa et al; 2007
- "HPHT Synthesis"; International Diamond Laboratories; 2009