Real vs Fake Pearls: The Tooth Test and Other Checks

Start by setting the right expectation

Before testing anything, it helps to know what you're likely holding. Most jewellery sold as "pearl" at fashion prices is honestly described as shell or imitation pearl — a coated bead, not a grown pearl — and there's nothing dishonest about that as long as the listing says so. The checks below are useful for confirming what you've got (especially with something inherited, bought secondhand, or vaguely described), not for catching out every affordable necklace as a "fake".

The tooth test

The simplest and most reliable home check: gently rub a pearl against the edge of your front tooth, using light pressure, not a hard scrape. A genuine pearl — saltwater or freshwater cultured — feels slightly gritty or sandy, because its surface is built from countless microscopic layers of nacre. A glass, plastic or shell-coated imitation feels perfectly smooth, with no texture at all. This single test catches the vast majority of fakes and costs nothing, but only do it on a pearl you already own; it's not something to try in a shop.

Weight and temperature

Genuine pearls feel a little heavier for their size than a hollow glass bead or a lightweight plastic imitation of the same diameter — pick up two similarly sized strands and the real one is noticeably denser in the hand. Real pearls also feel cool against the skin for the first moment of contact, the way other dense natural materials do, and warm up gradually; a plastic bead starts closer to room temperature and warms almost instantly. Neither check is conclusive alone, but together with the tooth test they build a consistent picture.

Look closely at the surface

Real pearls, especially freshwater cultured ones, are rarely perfectly uniform — expect faint ridges, slight variations in shape from one pearl to the next along a strand, and a soft, almost satiny lustre rather than a hard glassy shine. Imitation pearls tend to be suspiciously perfect: every bead exactly the same size and shape, with a uniform, almost plasticky sheen under light. A strand that looks too flawless to be natural usually is.

Check the drill hole

Where the string passes through, a genuine pearl shows a clean, slightly rough-edged hole straight through solid nacre, often with a very faint colour change right at the edge of the hole. An imitation bead's hole often reveals a different-coloured core underneath the coating — a flash of white plastic or glass visible where the outer layer has been drilled through and the coating is thinnest. A magnifying glass or even a phone camera zoomed in makes this much easier to see than the naked eye alone.

What the listing wording tells you

Sellers are generally specific about this because it's a legal labelling requirement in most markets. "Freshwater pearl" or "cultured pearl" means a genuinely grown pearl; "shell pearl", "imitation pearl", "Majorca pearl" or simply "pearl-look" all mean a coated bead. If a listing is vague and a large, perfectly uniform strand is priced very low, assume imitation rather than taking a bare "pearl necklace" title at face value — see our pearl types guide for the full breakdown of what each category actually is.

Why it usually doesn't matter which one you have

For everyday fashion wear, an honestly labelled imitation pearl does the job just as well visually as a cultured one, at a fraction of the price and weight. The tests above are worth doing out of curiosity, to value an inherited piece, or to confirm a secondhand purchase — not because imitation pearls are something to be caught out buying. The only genuine problem is a listing that misrepresents shell or glass beads as "genuine cultured pearl"; the material itself, correctly labelled, is a perfectly reasonable choice.

The quick version

Rub it gently on a front tooth — gritty means real, smooth means imitation. Weigh it in your hand against something you know is genuine if you have one to compare. Look for small natural irregularities rather than machine-perfect uniformity, and check the drill hole for a different-coloured core. None of these need special tools, and running two or three of them together will tell you almost everything you need to know before you decide how to care for or value the piece.