Lab-Grown Diamond Identification
Diamond synthesis, regardless of if it occurs deep in the Earth or in a production facility, is a complex phenomena depending on a limitless number of factors. It is not possible to find or create an ideal environment for diamond crystallization. That is why no perfect diamond exists. All diamonds, whether natural or synthetic, have all sorts of imperfections – inclusions, impurities, crystal lattice defects, etc. Different growth environments result in different sets of imperfections. However, these imperfections do not constitute a diamond – both mined and lab grown are real diamonds regardless of imperfections – but make it unique. A neverending study of diamond imperfections lead research institutions and gemological laboratories to the development of methods to distinguish lab grown diamonds from their natural counterparts. Some methods are quite simple, and consumers can perform those checks themselves. Others require assistance of an experienced jeweler, while some tests are only available at certain advanced research and gemological laboratories.
There are a few advanced machines that can correctly identify lab created diamonds. Fourier transform infrared spectrometer (FTIR) or energy dispersive X-ray fluorescence (EDXRF) can both detect traces of metal in a diamond, which comes from the molten metal catalyst the diamond was grown in.
A cathodoluminescence (CL) spectrometer can show different growth sectors in a diamond. Mined diamonds only have octahedral growth sectors, while a vast majority of HPHT created diamonds have both octahedral and cubic growth sectors.
DeBeers has developed two machines that can properly identify synthetic diamonds. The first, DiamondSure, measures light absorption at a very specific wavelength and is used as a preliminary check. The more advanced and expensive DiamondView machine uses shortwave ultraviolet imaging to look at fluorescence patterns in the diamond. This machine is similar to the cathodoluminescence spectrometer. Both of these machines are expensive and are usually only available at the major gemological labs like GIA, EGL, and IGI.