How do you recognize a gemstone?

Tips on how to recognize a gemstone can help, and we'll look at the most useful things to look for. More often than not, an expert appraisal is essential, but certain signs can put you on the right track.

Recognizing a gemstone by inclusions and refraction

There are several things you need to know to check whether a gemstone is real. Don't forget, however, that synthetic stones can look very good.

Inclusions are an interesting first feature to examine. You can detect them with a 10x magnifying glass. Synthetic stones tend to look too perfect. Also, some have specific defects (striations, air bubbles, marbling...), which depend on the manufacturing process and are rarely found on natural stones.

You can also recognize a gemstone by its refraction. Natural stones have a certain refractive index: the way light is deflected on the stone. Diamond, tourmaline and spinel , for example, have a high refractive index. These stones sparkle a lot. Imitations are duller, but synthetic stones are realistic in this respect.

Read also our article on how to recognize a sapphire.

Color to check if a stone is real

Color is a good criterion for examining a gemstone, semi-precious stone or stone of doubtful authenticity, but in parallel with other criteria. Genuine gemstones have small variations in color, such as lighter areas. Another example: traces of gray in a blue stone. This can sometimes be seen with the naked eye and natural light, but it's best to observe stones with a magnifying glass.

Synthetic stones are often more uniform. Which ones are brighter or paler depends on the stones. Indeed, a synthetic sapphire may have less intensity than a genuine high-quality sapphire, such as a Ceylon sapphire, and a genuine emerald may be paler than a fake one.

Overall, you can recognize a gemstone by its more subtle, heterogeneous play of color.

Learn more about synthetic stones and imitations

A synthetic stone has been manufactured in a laboratory and has the same physical properties as a real stone.

There are several manufacturing processes, and some are quite old. Some synthetic stones are indistinguishable from natural stones without professional equipment, as are many synthetic rubies and sapphires .

There's nothing wrong with using synthetic stones in jewelry, as long as they are presented as such. There are different levels of quality. Synthetic stones of lesser quality generally have characteristics not found in precious stones.

An imitation is a stone with different physical properties.

It can be artificially created, as is the case with moissanite in jewelry. It may be a genuine stone that looks like a more expensive one, but it's only an "imitation" if you've been deceived about its true nature.

Some imitations are excellent, especially diamonds, but they can fail a hardness test. They scratch more easily than real diamonds. Another tip for identifying a stone: a natural stone stays fresh longer than a fake one.

A gemmologist can recognize a precious stone

By performing several tests, you can sometimes recognize a gemstone or have strong suspicions. Nevertheless, no assessment is as reliable as that of a gemmologist, equipped with several tools, such as a microscope, refractometer and spectroscope.

To obtain a certificate of authenticity or to find out more about a gem, it is essential to consult a gemologist.