How to Tell If Pearls Are Real

A real pearl is nacre that a mollusk deposited. Cultured pearls qualify, because the animal still grows that nacre after a person inserts a bead or a piece of tissue. Imitations do not. They are manufactured beads, made of glass, plastic, shell, or a coated composite, and finished to look like pearls.

You can often catch an obvious imitation at home. You cannot, from a rub or a photograph, prove that a bead is natural rather than cultured, or saltwater rather than freshwater. Those differences are internal. Start with the least damaging observations, and stop before acid or heat.

The category definitions are set out in natural, cultured, and imitation pearls. This page is the hands-on screen.

Quick checks

Use the table as a screen, not a scorecard. One row can be wrong. Several rows pointing the same way are more useful.

Tooth test and friction test

Nacre is built from microscopic platelets of calcium carbonate held by organic material. Drawn once, very lightly, across the edge of a clean front tooth, that surface often feels slightly sandy. A glass or plastic imitation more often feels like a tiny polished marble.

The friction test makes the same comparison between two beads. A light rub of nacre against nacre can feel faintly resistant rather than oily. Do not press. Pearl hardness is only about 2.5 to 3 on the Mohs scale, so tooth enamel and a second pearl are both hard enough to wear the surface you are testing. The grit is that softer face catching. A second and third pass is abrasion, not a better experiment, and saliva does the bead no favors.

Skip both tests on an heirloom, a strand you might sell, or any bead that is already peeling. A gritty result is still only a clue. Mother-of-pearl shell is the same family of material and can feel gritty. Some imitation coatings are textured on purpose. A slick result is a reason to inspect that bead more closely. It is not a laboratory identification.

Luster, surface, and how evenly they match

GIA describes pearl luster as light reflected from the surface and from concentric inner layers of nacre. On a nacreous pearl the reflection often looks deep, with a shifting hint of color, rather than a single painted shine sitting on top. Rotate one bead beside a window and watch whether the glow seems to come from within the layers.

Blemishes do not settle identity. Surface spots are graded on mollusk-grown pearls, and a smooth face is also common on better imitations. Matching is one of GIA's pearl quality factors, and dealers sort cultured pearls into strands by size and color, so an even necklace can be entirely genuine. An imitation strand is even because the beads were made that way. Treat sameness as meaningful only together with the surface: identical color, identical drill holes, and a coating-like shine are more suspicious than matching alone. Baroque and irregular outlines occur in both mollusk-grown pearls and manufactured beads.

Weight and temperature

GIA lists a specific gravity of about 2.60 to 2.85 for pearl. Ordinary plastic is much less dense, so a plastic imitation of the same diameter usually feels light and reaches skin temperature quickly. A nacreous pearl tends to feel cooler at the first touch. Glass often does too. Heft and temperature can help you set obvious plastic aside. They cannot confirm nacre, and they say nothing about whether growth was natural or cultured.

Do not dunk a strand to compare density. Water swells silk thread, and household liquids can attack a coating, a dye, or the organic part of nacre. If you already have a jeweler's scale, record the weight of the whole item for your notes. That number is not an identity test.

Drill holes and a 10x loupe

Use a 10x loupe and bright, diffuse light. Look at the surface and the rim of one drill hole. Do not pick at the hole with a pin, needle, or toothpick.

On many nacreous pearls the surface shows a fine overlapping texture. GIA's examination of coated shell-bead imitations found the opposite: a glitter of minute particles instead of obvious nacre platelets, and chipping beside drill holes that exposed a white shell core. A thin coat that flakes, a sharp line of finish at the hole, or a core of another color is strong evidence of an imitation.

A bead-cultured pearl can show a boundary between the outer nacre and a shell nucleus when that nacre is thin or chipped at the hole. A clean rim does not prove the layer is thick. Dye, when present, sometimes concentrates at a hole or on the thread. That color line is a treatment clue. It does not, by itself, mean the bead is fake.

The growth pattern that separates natural, bead-cultured, and non-bead-cultured pearls is internal. A loupe does not reach it.

Freshwater, saltwater, cultured, and the main imitations

Keep the labels apart.

U.S. Federal Trade Commission jewelry guides define a pearl as a calcareous concretion of carbonate of lime and organic material formed in a mollusk without a person inducing that growth. A cultured pearl, in those guides, is the product created when a person plants a nucleus, usually a sphere of mollusk shell, and the mollusk coats it with nacre. An imitation pearl is any manufactured product made to simulate that appearance. The unqualified word pearl is for the natural product. Cultured or cultivated has to sit immediately in front of pearl for cultured goods. Imitation, artificial, or simulated has to do the same for imitations. Describing an imitation as real, genuine, or an unqualified organic pearl is treated as deceptive.

GIA's consumer answer matches the material split: cultured pearls are actual pearls formed with human help, and imitations are a different material, typically plastic, shell, or a composite.

Many Akoya, South Sea, and Tahitian cultured pearls are grown in saltwater on a bead. Freshwater cultured pearls are often grown from inserted tissue and may lack a round bead, though a bead nucleus is not limited to saltwater. A round, lustrous white bead can be either. Eye, tooth, and loupe checks do not name the water. In the laboratory, freshwater pearls tend to carry more manganese and saltwater pearls more strontium. That chemistry is not a kitchen test.

Radiography is how a lab sees the interior. Many natural pearls show concentric growth without a solid nucleus. Bead-cultured pearls show a core surrounded by nacre. Many non-bead cultured pearls show irregular growth or a void. Ask for that examination when a seller claims a natural pearl.

Imitations you are likely to meet:

• Glass beads with a pearl-like finish. A worn spot can show a glassy core, and a thin coat may reveal bubbles or swirl lines.
• Plastic beads, usually light, warm, and slick, sometimes with a mold line.
• Shell beads, including pieces marketed as shell pearls. GIA has documented shell cores under a thin artificial coat, with chipping at the drill hole, sold in language that simply said pearl. The accurate name is imitation pearl.
• Majorica, made in Mallorca. The company states that its pearls are neither natural nor cultured. Its FAQ describes round beads on a mother-of-pearl shell core and baroque beads on a Murano glass core, each finished with many layers of a proprietary coating. That is a manufactured imitation, even when the coating uses marine ingredients. The FTC guides also require a regional name such as Mallorca pearls to carry an immediate cultured or imitation qualifier. Other workshops use the island's name for different products, so a clasp that says Majorca is a claim to read, not a certificate.

Conch and melo pearls are a separate case. They can be genuine mollusk products with a porcelain-like surface and little nacreous play of color. The grit test and the platelet look are the wrong tools. If that is the question, stop and use a laboratory.

Vinegar, boiling water, and flame

Do not use vinegar. Pearl is calcium carbonate, and GIA's care guidance says pearls can be damaged by many chemicals and by all acids. Vinegar is an acid. It can leave a permanent dull pit, and the fizz people hope to see is gas coming off that dissolving surface. The reaction is not specific. Mother-of-pearl and other shell are calcium carbonate too, so a shell imitation can fizz while a pearl is being etched. Glass and plastic may sit unchanged, which only tells you the exposed face was not a carbonate. If a coating hides a shell core, you can ruin the bead before you learn anything. No drop size makes this a safe test.

Do not use boiling water, a lighter, or a hot needle. GIA states that high heat can burn cultured pearls or cause discoloration, splitting, or cracking. Heat also weakens silk, adhesives, dyes, and coatings. A smell of scorched plastic would mean the item is already damaged, and a nacreous pearl can be scorched without revealing whether growth was natural or cultured.

After a gentle look, care stays conservative: a soft cloth, and warm soapy water only when the strand and any treatment can tolerate it. The pearl care guide covers wiping, drying, and storage. Ultrasonic and steam cleaners are not for pearls.

When a gemologist or laboratory is the right next step

Book an independent examination when money, insurance, an estate, or a sale depends on the answer, or when the beads might be natural, conch, or melo. A loupe and a spoken opinion at the counter can be useful. They are not a report.

A pearl identification report can state whether the material is natural or cultured, how it was nucleated, whether the environment was saltwater or freshwater, the mollusk when that can be determined, and treatments the lab can detect, including dye, bleaching, optical brightening, or a coating. Ask which of those questions the service covers before you ship the piece. The document is not an appraisal. If you need a number, decide first whether you mean retail replacement or a resale figure. The retail, resale, and insurance value guide separates those questions.

Photograph the piece before it leaves your hands. Identify jewelry by type collects the photo lists. For a strand, use how to identify a necklace: the full strand, the clasp, and a close view of the drill holes. Studs and drops belong on how to identify earrings. Bracelets and rings have their own lists at identify a bracelet and identify a ring. If the clasp is stamped, record the whole mark and read it from the hallmark index, including what 925 means or what 750 means when those numbers are the ones you see. A metal mark is a claim about metal. It does not make the beads pearls.

What the Jewelry Identifier app can and cannot confirm

The one-photo identification preview and the Jewelry Identifier iPhone app read images. A sharp photo can help organize what is in frame: a strand, studs, or a pendant; approximate color and shape; obvious peeling or a mismatched core at a hole; a legible clasp mark; and the condition of the string. The result can suggest a sensible next step, and it should state what the picture does not support.

It cannot feel grit, measure density, see through the bead, or confirm nacre, natural versus cultured origin, saltwater versus freshwater origin, dye, coating, or value. Wording on a screen is still a reading of pixels. Keep the photo as a record, then decide whether the purchase or the heirloom needs a laboratory.

The download control on this page uses the same App Store listing as the rest of the site. Features and price shown there are the current ones: Jewelry Identifier on the App Store. Availability can differ by storefront.

How can you tell if pearls are real?

Compare luster, one gentle tooth or friction check, and the drill hole under a loupe. Chipped coating or a different-colored core is strong imitation evidence. None of these steps proves that a bead is natural, cultured, saltwater, or freshwater.

Are cultured pearls real pearls?

Yes. Cultured pearls are nacre grown by a mollusk after a person inserts a bead or tissue. Imitations are manufactured from other materials, such as glass, plastic, shell, or a coating over a core, and should be sold as imitation.

Does the tooth test prove a pearl is real?

No. A slight grit can fit nacre or shell, and some coatings feel textured. Enamel is harder than pearl, so repeating the rub wears the surface. One light pass is a clue, not a verdict.

Why is the vinegar test a bad idea?

Vinegar is an acid, and pearl nacre is calcium carbonate that acids etch. The dull spot is permanent, and shell imitations can fizz too, so the reaction does not identify a pearl. Boiling water and flame can crack or burn the bead and the string.

Can a photo or the app confirm real pearls?

A photo can record shape, color, peeling, drill-hole edges, and clasp marks. It cannot confirm nacre or origin. Use the photo identification page to organize those clues, then use a gemological laboratory when the answer matters.