How to Tell Real and Fake Pearls Apart
Recognizing Real Pearls
Pearls are beautiful. There are faux (fake) pearls that look stunning and real pearls that look... well... less so. So why care whether or not you can tell real and fake apart?
You will want to be able to recognize real pearls if you are buying them because precious gems can be a good investment. High quality genuine pearls cost considerably more than those made of glass or plastic. Also, real pearls can last indefinitely if given proper care, while fake ones are more susceptible to chipping and peeling.
Definition of Terms
By "real," we mean both natural and cultured pearls. Before the 1920s, all pearls were found in nature ("natural"). Since then, we've learned how to "plant" an object in a bivalve's shell and grow "cultured" pearls that way. Although they didn't start naturally, cultured pearls are real, with outer coatings of the same material, and like natural ones, they take years to form.
Real vs. Fake
Both real and fake pearls can be beautiful, but it's important to know which type you have. Reputable stores may identify faux ones with terms like fake, simulated, faux, glass, plastic, synthetic, resin, artificial, or manmade.
There are several different types of genuine pearls. There are rare natural ones that occur spontaneously in the wild and cultured pearls which are a combination of manmade and mollusk-made, fresh water (from rivers, lakes, ponds) or saltwater (sea or salt marsh), and those that come from a variety of different kinds of mollusks. There are shell pearls and genuine pearls which have had treatments applied to them, such as coatings or faceting.
Methods of Telling Real from Fake Pearls
If you cut a pearl open, you will see its true nature.
- Natural pearls are comprised of layer upon layer of nacre. At the center, you'll find whatever object it was that got inside the bivalve and began irritating the creature. To protect itself, the bivalve coats that object (usually a piece of sand) with nacre.
- Cultured pearls usually have a shell (mother-of-pearl) core covered with thin layers of nacre (generally no more than half a millimeter per layer, usually much thinner).
- Fake pearls have a core with one or more layers of coating applied to them, which tends to flake away from the core upon cutting.
Cutting a pearl can also reveal the nature of its drill hole, if present. Of course, for this test to be relevant, you need to be able to tell pearl-colored glass from shell (although plastic and resin are easier to discern). Also, you'll destroy the pearl, so it isn't recommended.
If you really need to know whether or not your pearls are real or if they are natural or cultured, you are going to have to pay someone, preferably a certified gemologist, to do an x-ray. An x-ray will show the inside of the pearl, including variations in density, what caused the formation of the layers of nacre, and the characteristic shapes of drill holes, if present. This is an expensive test and therefore won't be feasible for most people.
The Tooth Test
To use the tooth test, you rub the surface of the pearl over your teeth. Supposedly a real pearl feels gritty while a faux one feels smooth.
The premise behind the test makes sense: Real pearls are made up of layers of nacre that are deposited rather like sand on a beach. The slight waves and irregularities in the nacre can produce a gritty or bumpy feeling against the teeth. On the other hand, many synthetic nacres are applied smoothly onto perfectly smooth beads, and thus feel smooth against the teeth.
The test is pretty good for distinguishing rare natural pearls from glass pearls, but it isn't as good at identifying cultured pearls, which have fewer layers of nacre and may feel more smooth. Also, if the pearls are dyed, the dye can fill in natural depressions in the pearls, making them feel smooth. Plus, some synthetic pearls are made to look and feel like real pearls. Mabe pearls may have a protective coating applied to them, which makes them smooth even though they are genuine.
The tooth test is a nice test, but don't base your judgement of authenticity on this test alone. If you think it's reliable, I swear I could find pearls that would fool you, both real and faux.
The Sun Test
This is my favorite test. It involves taking your pearls out into the sun or holding them under very bright indoor lighting. Unless they are very expensive, genuine pearls won't be perfectly matched under the sun. You will be able to see variations in their iridescence and color. If you focus specifically on the section of each pearl that reflects the light, you'll see variations in color, size, and shape. If the pearls are perfectly matched for color and overtones, they are most probably fake.
If you are buying pearls from a seller who offers ones that are perfectly matched, the cost of a gemologist certificate (for a gemologist of your choice, not his) is a minimal part of the investment. It costs about $150 to have pearls tested, as opposed to several thousands of dollars for the type of pearls that warrant the test.
As is true with diamonds, magnification reveals a lot about the quality of a pearl. With a loupe, you can see the characteristic ridges and irregularities of real pearls or the grainy smoothness of fakes. You can examine drill holes to see the interface between the nacre and what lies beneath it. You can also read any writing on the clasp or setting.
Other Visual and Tactile Cues
- Fakes tend to look flat in comparison to the real thing. There are exceptions, of course, with beautiful simulated pearls made by Swarovski and other manufacturers.
- Real pearls tend not to be perfect and may have bumps, ridges, pits, or bands in their nacre. They also may have concentric ridged circles around them, which inexperienced people may take for marks from molding of a fake (which is seen in the exact middle of all the pearls on strands of some faux pearls). Some fakes are made to look irregular, and glass pearls often have flattened ends or slightly oval shapes.
- Real pearls vary in size and shape. They come in many shapes but tend not to be perfectly round, so a perfect sphere should be suspect. Expensive genuine pearls may be round, but you will have other clues to help you make a determination.
- Density is the mass of an object as a function of its volume. Real pearls are heavier for their size than plastic, resin, or hollow glass beads. Light pearls are fake, but good glass fakes will have the same density as real pearls. You can't tell real from faux on the basis of density alone if the pearls are heavy.
- Genuine pearls tend to warm to the skin much faster than glass ones. Resin and plastic tend to feel somewhat warm upon first contact.
- Real pearls tend to be drilled from both sides to meet in the center. If you could see the cross section of the pearl, the hole may appear wider at the outside edge than at the center (which can make stringing poorly-drilled pearls very challenging and is one reason many jewelers won't restring pearls that they didn't sell).
- Holes of real pearls tend to be as small as possible (with some exceptions), since the weight of a pearl effects its price (more hole means less weight and lower value). Inexpensive real pearls may be lower in cost because the drill holes are larger or not completely straight. Fake pearls often have larger, possibly straighter holes than real pearls, but some fakes are made to have smaller holes, so that they can be knotted like their genuine counterparts. Inexpensive fakes may have holes of variable sizes on a single strand.
- The nacre of fake pearls is more likely to flake away near the drill hole than on a cultured pearl (it won't flake on a natural pearl). Either the flaking or the sight of a clear inner bead may clue you in to a fake. Most fakes have pearl-colored centers, so the center color may not help you. The holes of fakes often form a shallow bowl shape, while the holes of real pearls are more likely to be flat. Examining the hole is also a good way to detect signing of dyeing.
The Quality of the Setting
If you see the Mona Lisa in someone's home, you can be sure it isn't the original piece of artwork. Similarly, you can gain valuable clues about a pearl's authenticity by looking at its surroundings.
- In a finished necklace or bracelet, real pearls are more likely than faux to have knots between each pearl.
- Real pearls are more likely to have settings of gold, silver, or platinum. Some fakes have high quality settings, and some genuine pearls have cheap settings; even so, the setting can provide clues to help you reach a conclusion.
- You can examine clasps for stamps or engravings in the metal or for magnetism (indicating the clasp or setting contains iron as opposed to a precious metal). The clasps of genuine pearls tend to have safety mechanisms, like fish hooks, but some are sold with other types of clasps, usually as an accommodation for a person who might have difficulty with opening/closing the clasp. It isn't a hard-and-fast rule; however, insecure clasps are not usually seen on good pearls.
These Pearls Are Real
These Pearls Are Probably Real
You can identify the origin of certain pearls by the color they glow when exposed to ultraviolet (black) light.