Cultured pearl vs real pearl: what the FTC Jewelry Guides make sellers say

In the FTC's Jewelry Guides, a "pearl" is the rare one that forms with no help from people, and nearly everything sold as a pearl today is a cultured pearl or an imitation. A seller may use the bare word pearl only for the first kind. Cultured pearls must be called cultured or cultivated, and imitations must be called artificial, imitation or simulated. All text below is from 16 CFR Part 23 as published in the eCFR on October 22, 2026.

The three definitions

Section 23.19 sets the vocabulary. A pearl is "a calcareous concretion consisting essentially of alternating concentric layers of carbonate of lime and organic material formed within the body of certain mollusks," the result of an abnormal secretory process that has not "in any way been caused or induced by humans."

A cultured pearl is "the composite product created when a nucleus (usually a sphere of calcareous mollusk shell) planted by humans inside the shell or in the mantle of a mollusk is coated with nacre by the mollusk." So the mollusk still does the coating. The human part is the nucleus.

An imitation pearl is "a manufactured product composed of any material or materials that simulate in appearance a pearl or cultured pearl." Nothing in that definition involves a mollusk at all. The guide also defines a seed pearl as a small natural pearl measuring approximately two millimeters or less.

What a seller must say

Section 23.20 turns the definitions into rules. It is unfair or deceptive to use the unqualified word pearl for anything that is not a pearl as defined. A cultured pearl needs "cultured" or "cultivated" in front of the word, "with equal conspicuousness." An imitation needs "artificial," "imitation" or "simulated."

The section also closes the loophole of friendly-sounding labels. The terms "faux pearl," "fashion pearl" and "Mother of Pearl" used to describe an imitation pearl product also need the qualifier in front.

Section 23.21 adds a long list of banned shortcuts. A few that matter for shoppers:

• Cultured pearl wording may not be used for an imitation (23.21(a)).
• "Natural," "natura" or "nature's" may not describe a cultured or imitation pearl (23.21(e)).
• "Real," "genuine" or "precious" may not describe an imitation pearl (23.21(i)).
• "Synthetic" may not describe a cultured or imitation pearl (23.21(j)).
• Regional labels such as Japanese pearls, Chinese pearls or Mallorca pearls need cultured, artificial, imitation or simulated in front (23.21(k)).

Two place-name rules are worth knowing. "South Sea" may be used only for a pearl from a salt water mollusk of the Pacific Ocean South Sea Islands, Australia or Southeast Asia (23.21(g)). "Biwa cultured pearl" is reserved for cultured pearls grown in fresh water mollusks in the lakes and rivers of Japan (23.21(h)).

Is a cultured pearl a real pearl?

The Guides do not define "real" for pearls. They bar "real" and "genuine" for imitation pearls and bars "natural" for cultured and imitation ones, and it leaves the bare word pearl to the unassisted kind. That makes the label the thing to read. A string described as "cultured pearls" is a string of coated-nucleus pearls. A string described as "pearl" with no qualifier, at a low price, deserves a second look.

Wikipedia's entry on pearls explains the same split in plain terms: natural pearls form without human intervention and are very rare, while cultured pearls are made on farms by implanting mantle tissue into a shell. The entry credits Tokichi Nishikawa and Tatsuhei Mise with bringing pearl culture to Japan, notes that "Nishikawa was granted the patent in 1916," and says that, "Despite the common misperception, Mikimoto did not invent pearl culture."

Where the market sits

The entry says cultured pearls "make up the majority of those currently sold" but gives no percentage. It does give production facts. Most freshwater cultured pearls sold today come from China, and "China has since become the world's largest producer of freshwater pearls, producing more than 1,500 metric tons per year," a figure the entry does not date. It also says that "In 2010, China overtook Japan in akoya pearl production." Treat those as secondary figures from a reference work rather than audited statistics.

The same entry lists the main saltwater types. Akoya pearls come from Pinctada fucata and are usually 2 to 10 mm, typically cream or white. South Sea pearls come from Pinctada maxima and are the largest and rarest cultured pearls. Tahitian pearls, known as black pearls, come from Pinctada margaritifera.

Treatments and misrepresentation

Pearls can be treated, and the Guides say when that must be disclosed. Section 23.23 says it is unfair or deceptive to fail to disclose a treatment if it is not permanent, if it creates special care requirements, or if it significantly affects value. Section 23.22 goes further and bars misrepresenting how cultured pearls are produced, the size of the nucleus, the time in the mollusk or the thickness of the nacre coating.

How to read a pearl listing

• Find the qualifier. Cultured or cultivated should sit directly in front of pearl at the same size.
• Check the origin word. South Sea, Biwa or a country name carry limits under 23.21.
• Treat "faux," "fashion" and "Mother of Pearl" as signs of an imitation unless a qualifier says otherwise.
• Ask about treatment if a color looks uniform or unusually vivid. The Guides ask sellers to disclose non-permanent treatments.
• Remember the Guides are not binding law. Section 23.0(d) says they do not bind the FTC or the public, though the Commission may act on claims inconsistent with them.

Wikipedia also describes a rub test: imitations feel completely smooth, while natural and cultured pearls feel slightly gritty. It is a hint, not a lab result, and we would not pay on the strength of it.

Our take

The useful distinction for a shopper is cultured versus imitation, not cultured versus real. Both of the first two are pearls made by a mollusk, one with a human-planted start. The third is a manufactured simulation, and under the Guides it cannot borrow the words real, genuine or cultured. Buy on the qualifier, ask about treatment, and skip any listing that uses pearl wording with no qualifier at a price that does not fit. For a related look at how another material is policed, see our piece on what the FTC says about genuine leather.