05. How can you tell a real pearl from an imitation?

We often wonder if a pearl is real or fake. Here are the simple techniques I use myself, the ones we learn during training, and which almost never fail.

1. The most reliable test: the tooth

Gently rub the pearl against the edge of your front teeth. A real pearl, whether cultured or natural, has a slightly granular surface: you will feel a fine grain, almost like very fine sand. A plastic or faux-pearl glass bead will slide off, completely smooth. This texture comes directly from the structure of the nacre, made of thousands of fine stacked platelets—a material no imitation truly replicates.

2. Weight, a simple indicator

A real pearl has a certain weight in the hand, heavier than one might imagine for its size. Plastic imitations are significantly lighter. This test alone is not enough, but combined with the others, it quickly confirms an intuition.

3. Look closely at the surface

Under good light, a real pearl is never perfectly smooth or perfectly uniform. You can see slight irregularities, small surface variations, and sometimes a visible grain. An imitation, on the other hand, often displays a luster that is too regular—almost plastic-like—without the slightest variation.

4. Examine the drill hole

If the pearl is set in a piece of jewelry, look at where it is drilled. On a real pearl, you can distinguish the fine layers of overlapping nacre, like the rings of a tree. On an imitation, the hole often reveals a uniform material, sometimes just a simple layer of pearlescent paint that flakes off over time.

5. What light reveals

This is my favorite test, the one I have used instinctively since my training. Rotate the pearl gently under a light and observe its glow. A real pearl has a deep, almost shifting luster, with reflections that change depending on the angle. An imitation remains flat; it shines as a single solid, always in the same way.

“A real pearl never shines as one flat block: its light seems to come from within.”

One final rule of thumb, the simplest of all

If a pearl piece is sold at a price that seems abnormally low for the material claimed, it is often the most reliable sign of all. A real cultured pearl requires years of growth and rigorous selection before it reaches you, and that is always reflected somewhere.

Why I wanted to share this with you

Every pearl that enters my collections goes through these same motions before it is even mounted. It is a reflex I perform without thinking, and I wanted you to be able to do the same, for your own jewelry, whether old or new.