How to Differentiate between Synthetic and Imitation Gems?

A natural gemstone comes from the ground and is a product of nature, not of man.

The word synthetic is used to describe a gemstone made in a lab that has the same basic chemical composition as its natural counterpart. For example, synthetic ruby has the same chemical composition as natural ruby. It also has similar chemical, optical and physical properties.

Imitations, on the other hand, do not have the same chemical composition as the stones they resemble, and they may be made by nature or by man. Red glass, for example, can be a man-made imitation of ruby. Garnets used to mimic rubies would be natural imitations.

Since consumers tend to interpret the word “synthetic” differently than jewelers, people who sell synthetic stones usually prefer to describe them with terms such as created, lab-grown or man-made. Gemologist and natural stone dealers usually identify lab-grown stones as synthetic stones.

Cultured is sometimes used incorrectly as a synonym for “lab-grown.” The two terms however, are not equivalent. For example freshwater cultured pearls, culturing pearls is a more natural process than growing gems.

Synthetic gems are not just a recent phenomenon. Lab-grown ruby, the first synthetic, has been sold commercially since the early 1900’s; if your great grand mother has some ruby jewelry, the stones could very well have been made in a laboratory. Today, lab-grown stones are even more common especially in birthstone jewelry and class rings. Synthetic stones are also found in designer jewelry, set with diamonds in gold or platinum. Some of the stones that are synthetically produced and sold to consumers in jewelry are:

Synthetic alexandrite
Synthetic amethyst
Synthetic chrysoberyl
Synthetic diamond
Synthetic emerald
Synthetic opal
Synthetic ruby
Synthetic sapphire
Synthetic turquoise
Synthetic pearls

Some stones call imitation stones “synthetic.” For example, imitation tanzanite may be sold as “synthetic tanzanite” because “synthetic” sounds better than “imitation.” Green CZ (cubic zirconia) is often called synthetic emerald. Green CZ is a lab-grown stone, but it’s not synthetic emerald. It’s synthetic CZ, which is much cheaper than lab-grown emerald.

In most countries, it’s against the law to call a synthetic ruby, for example, simply a ruby. Not all countries, however, have laws like this and some stores don’t follow the law. Therefore when buying expensive gems abroad, have the store specify on the receipt if the stone is of natural origin. This is added protection for you. Technically synthetic ruby is ruby. Ethically, though, it should be called synthetic or lab-grown ruby.