Pearls come in many shapes and sizes whether they are real or not, and it’s not always easy to tell the difference between the genuine article or a fake. Even amongst genuine pearls there are many different classes of both natural and cultured varieties, all with their own different properties and all valued very differently as pearl jewellery. Before buying any pearls it’s important that you know what you’re getting, so here are a few ways to help differentiate between a genuine pearl and a fake:

The Tooth Test
It’s said that if you rub a pearl against the biting edge of your front teeth, you can tell whether it’s real or fake by the feel of its surface. Real pearls normally have a more rough, irregular texture whereas fakes are glassy and perfectly smooth. This isn’t really the most reliable method of testing, as fakes are often made to appear completely genuine and cultured pearls in particular can often be very smooth, especially if they are dyed.

The Sun Test
Another indicator is to take the pearls into full daylight and look closely at the lustre, or iridescence, that you see on the surface. Unless they are extremely rare and expensive, genuine pearls won’t be perfectly matched under the sun and you will be able to see slight imperfections in the colour and lustre.

Surface Magnification
Don’t underestimate the power of a magnifying glass – a closeup look at the pearl earrings, necklace or brooch can tell you a lot, and is one of the most effective ways of distinguishing between genuine and fake pearls. Genuine pearls are covered in tiny, almost indistinguishable lines, making it look almost scaly under magnification. Whilst there you could also take a look at the small drill holes at either end of the pearl, which are normally as small as possible in a real pearl as larger holes devalue the gem. Real pearls usually have holes drilled from either end, so the hole is much smaller in the middle of the pearl.

One of the most obvious ways to identify real pearl sets is to look closely at the shape of each pearl and whether or not they are close to being identical – real pearls are hardly ever perfectly round, and it is almost unheard of to find a whole string of pearls of exactly the same size, shape and weight. Real pearls that are regular in this way are extremely expensive, and if not they are probably fake.

The only truly reliable way to be sure a pearl is authentic is to pay a certified gemologist to verify it. For a fee they will be able to x-ray the pearls, allowing you to see inside to any imperfections or variations in density and identifying the nucleus to determine how the pearl was originally formed. To be worth paying the price you need to first be fairly sure that the pearl is genuine, but some fakes can be very convincing and it’s the only way to really be 100% sure without damaging the pearl.