If you have inherited a strand of pearls or spotted some at a market, you may wonder whether they are real. There are a few simple checks you can do at home, and this guide runs through them, along with the tell-tale signs of an imitation and when it is worth asking a jeweller.
To tell if a pearl is real, gently rub it against the edge of your tooth: a real pearl, natural or cultured, feels slightly gritty, while an imitation feels smooth and glassy. Real pearls are also cooler to the touch, a little heavier, and have tiny surface irregularities and subtle colour, where fakes look perfectly uniform. Remember that a cultured pearl is a real pearl.
Real or imitation: what you are actually testing
Before the tests, it helps to be clear about what real means. A real pearl is one grown by a mollusc, whether it formed naturally or was cultured on a pearl farm. An imitation, sometimes called a faux or costume pearl, is a bead of glass, plastic or shell coated in a pearly lacquer to look the part. So these checks are really about telling a genuine pearl from an imitation, and a cultured pearl will pass every one of them, because it is real. Our guide to cultured vs natural pearls explains that distinction in full.
The tooth test
The best-known test is the simplest. Rub the pearl gently along the biting edge of your front teeth. A real pearl has a very fine, textured surface, so it feels slightly gritty or sandy, a little like fine sandpaper. An imitation, with its smooth coated surface, feels glassy and slides cleanly. It works because a real pearl is built from countless microscopic layers of nacre, which the fake simply cannot copy. One honest caveat: the finest imitations are made with a textured coating that can mimic this, so treat the tooth test as a strong first clue rather than the last word, and back it up with a check or two below.
Other simple checks you can do at home
No single test is perfect, so it is best to use a few together. These need nothing more than your hands and eyes.
- Temperature. Real pearls feel cool when you first pick them up and warm slowly against the skin. Many plastic imitations feel room temperature straight away.
- Weight. Real pearls have a little heft for their size. Hollow or plastic fakes often feel surprisingly light.
- Surface. Look closely, ideally with a loupe. Real pearls show tiny bumps, ridges and slight imperfections, and no two are identical. Imitations tend to be flawlessly smooth and perfectly matched.
- Lustre and overtone. Real pearls have a deep lustre with subtle overtones of colour and gentle variation from pearl to pearl. Fakes often have a flat, uniform, almost mirror-even shine.
- Rubbing two together. Gently rub two pearls against each other. Real ones grip slightly and may leave a faint powder that brushes away, while fakes glide smoothly.
The tell-tale signs of a fake
A few things give an imitation away almost at once. Fakes are often too perfect, every pearl exactly the same size, shape and colour, with a mirror-even shine. They can feel too light, and warm to the touch straight away. Look closely at the drill hole where the pearl is strung, since an imitation often shows a painted or peeling coating, or a visible seam, around the hole, where a real pearl shows clean nacre. And, as ever, a strand of large, flawless pearls at a bargain price is almost certainly not real.
| Check | Real pearl vs imitation |
|---|---|
| Tooth test | Real feels gritty. Fake feels smooth and glassy. |
| Temperature | Real feels cool at first. Fake often feels room temperature. |
| Weight | Real has some heft. Fake can feel light or hollow. |
| Surface | Real has tiny irregularities. Fake is flawlessly smooth. |
| Matching | Real varies slightly. Fake is perfectly uniform. |
| Drill hole | Real shows clean nacre. Fake may show paint, a seam or peeling. |
When to have a pearl checked
If a piece is valuable, inherited or you simply want to be sure, a jeweller or a gem laboratory can confirm whether a pearl is real, usually in moments. A laboratory can go further and tell a cultured pearl from a rare natural one, which the home tests cannot: an x-ray reveals the small bead at the centre of many cultured pearls, something a solid-nacre natural pearl does not have. This is worth doing for an old strand that might, just possibly, be natural, since genuine natural pearls can be very valuable.
Start with the tooth test: gritty means real, smooth means fake. Then confirm with a couple more checks, real pearls are cool at first, a little heavy, slightly irregular in surface and subtly varied in colour, while imitations are perfectly uniform, often light, and may show a painted or peeling drill hole. Use several tests together, and if it matters, have a jeweller confirm it. And remember a cultured pearl is a real pearl.
This sits within our wider guide to pearls, alongside our guides to the types of pearls and caring for pearls. Every pearl in our pearl bracelets, pearl studs and pearl pendants is a genuine cultured pearl, set in solid gold.
