There are many ways to tell the difference between a natural mined diamond and a synthetic or man-made diamond, even though they’re structurally and chemically the same. Due to the process and technology used to make synthetic diamonds, trained gold and diamond buyers can identify synthetic diamonds, which are lower in value as they’re not nearly as rare. Here’s a look at some methods a jeweler can use to differentiate a synthetic diamond from a natural diamond.
One method is to use a fiber optic light, which can tell whether inclusions visible to the naked eye are metallic or reflective. This confirmation of metallic flux remnants in a diamond is proof that the diamond was made in molten metal in a lab and not in the earth.
If the synthetic diamond does not have visible inclusions different methods must be used. A jeweler can inspect the shape of the crystals, which are different than those of a natural diamond. While an expert cutter can remove the top cover of the crystal, there is no way to change color zoning and graining. The graining pattern differs because of the growth patterns. An hour glass graining can be observed in a synthetic diamond under magnification.
If differences can’t be observed in the structure of the crystals, graining or color zoning, the UV radiation test may be used next. Most natural mined diamonds will fluoresce blue under UV long wave and yellow under UV short wave. Synthetic diamonds will fluoresce a color between yellow and green under both.
Some synthetic diamonds have metallic inclusions so a magnet may be used to tell the difference. Man made diamonds will tend to gravitate toward a strong magnet, unlike a mined diamond. Natural diamonds have never been known to contain any kind of metallic inclusions.