There has been a swell of growing concern about a diamond imitation -- known as synthetic moissanite -- that has entered the retail marketplace.

In fact, ABC News recently dubbed synthetic moissanite "a scientific miracle. It’s more brilliant than a diamond, it’s as hard as a diamond, and if you place it under a jeweler’s electronic diamond tester, it will pass for a diamond."

Well, let us put your mind at ease. In the hands of a fully qualified GIA Graduate Gemologist (G.G.), detecting synthetic moissanite is a simple and foolproof process. Indeed, so simple, that all you need is a standard jeweler's loupe to make the detection.

An easy way to distinguish synthetic moissanite from diamond is to look for double refraction, or ‘doubling'. Diamond is an isotropic (singly refractive) material, so it does not exhibit ‘doubling.’ To detect doubling (i.e. single facet edges, scratches, or other objects seen as double images when looking through a doubly refractive gem) use at least 10-power magnification, such as a standard jeweler’s loupe, look in a bezel facet, and focus through the stone onto the gem's pavilion facet junctions.

At each facet junction, look for two lines very close together, instead of one. 'Doubling' can be seen in any moderate to strongly doubly refractive gem material, such as synthetic moissanite, zircon, or peridot. The higher the magnification, the easier it is to see the 'doubling'.

Another technique for detecting synthetic moissanite is to look at the stone's inclusions. A synthetic moissanite may have distinctive sub-parallel needle-like inclusions or ‘stringers’ oriented perpendicular to the table. It may also have rounded facet junctions, polish lines that run in the same direction on adjacent facets, and an undiamond-like girdle appearance. Improved manufacturing techniques may change these observations in the future.

A quick way to determine whether a parcel of diamonds is mixed with synthetic moissanite is to use a heavy liquid, such as methylene iodide (which has a specific gravity (S.G.) of 3.32). Diamond's S.G. is 3.52, so it sinks in this liquid, whereas synthetic moissanite, with an S.G. of 3.22 floats.