What Are Natural, Cultured and Imitation Pearls?
Short answerA natural pearl formed inside a mollusk with no human help. A cultured pearl also grew inside a living mollusk, but only after a person implanted a bead or a piece of tissue to start it. An imitation pearl is manufactured, usually a glass, plastic or shell bead with a pearly coating, and never grew in a mollusk. US rules and CIBJO standards require cultured and imitation pearls to be labeled as such.
- In the United States, the word "pearl" on its own may only describe a natural pearl.1
- A cultured pearl must be called "cultured" or "cultivated", and an imitation "imitation", "artificial" or "simulated", in letters as clear as the word "pearl".1
- "Real", "genuine" and "precious" may not describe imitation pearls, and "natural" may not describe cultured or imitation pearls.1
- Cultured pearls make up the vast majority of pearl sales today.2
- Common imitations are solid or hollow glass, plastic or shell beads coated with a "pearl essence" that mimics the iridescence of nacre.3
- CIBJO recommends labeling natural pearls as "natural pearls" to avoid confusion.4
On this page
Every pearl for sale belongs to one of three groups: a natural pearl, a cultured pearl or an imitation pearl. The first two grow inside a living mollusk, and the third is manufactured. The words matter, because US rules and the jewelry trade’s own standards control how each one may be described.
Text version of this diagram
A tree with the three kinds of pearl at its tips. Something that looks like a pearl either grows inside a living mollusk or is manufactured. Of those that grow, a natural pearl forms with no human help, and a cultured pearl is started by a person, either with a shell bead and a piece of tissue or with tissue alone, as almost all freshwater pearls are. A manufactured one is an imitation pearl, usually a glass, plastic or shell bead with a pearly coating.
Natural pearls#
A natural pearl is a pearl whose formation was in no way caused or induced by humans. US guidance defines it as a concretion of alternating concentric layers of carbonate of lime and organic material, formed inside certain mollusks after an irritation or an abnormal physiological condition.1
CIBJO, the international jewelry confederation, adds that natural pearls form in naturally formed pearl sacs, and that they can be nacreous or non-nacreous.4 Conch, clam, scallop and Melo pearls are natural pearls with no nacre.4
Natural pearls are rare today. Thousands of years of pearl fishing have depleted the natural pearl beds,2 and hundreds of pearl oysters or mussels must be opened to find even one natural pearl.5
Cultured pearls#
A cultured pearl is grown by a living mollusk too, but people start it. US guidance defines it as the product created when a nucleus planted by humans, usually a sphere of mollusk shell, is coated with nacre by the mollusk.1
CIBJO’s definition is broader: a cultured pearl forms inside a living mollusk, within a cultured pearl sac, with human intervention.4 That covers pearls grown around a shell bead placed with a piece of mantle tissue, and pearls grown from tissue alone,6 as almost all freshwater pearls are.7
Cultured pearls make up the vast majority of pearl sales today.2 The page natural vs cultured pearls compares the two.
Imitation pearls#
An imitation pearl is a manufactured product, of any material, that only looks like a pearl or a cultured pearl.1 CIBJO also calls imitations simulants.4
Common imitations are solid or hollow glass, plastic or shell beads coated with a “pearl essence” that mimics the iridescence of nacre.3 The company behind the Majorica brand began in the early 1900s with glass beads coated with man-made resins, and its later imitation coats a glass bead with an essence made from fish scales.8 Shell-bead imitations, sold as “shell pearls”, have a long history in the jewelry market.9 CIBJO also counts the coque de perle, a section of nautilus shell finished to look like a half-pearl, as an imitation.4
The page real vs imitation pearls compares imitations with real pearls, and how to tell if pearls are real explains the tests.
The words sellers may use#
In the United States, the Federal Trade Commission’s Guides for the jewelry industry set out which words may describe which kind of pearl. A qualifying word must come immediately before “pearl”, with equal conspicuousness.1 The table sums up the main rules.
| Word or phrase | May be used for |
|---|---|
| “Pearl” on its own | Natural pearls only |
| “Cultured pearl” or “cultivated pearl” | Cultured pearls, never imitations |
| “Natural” | Natural pearls, never cultured or imitation pearls |
| “Real”, “genuine” or “precious” | Never imitation pearls |
| “Synthetic” | Never cultured or imitation pearls |
| “Imitation”, “artificial” or “simulated” | Required in front of “pearl” for any imitation |
| “Faux pearl”, “fashion pearl” or “Mother of Pearl” | Imitations, only with “imitation”, “artificial” or “simulated” in front |
| “Oriental pearl” | Natural saltwater pearls of the Persian Gulf type only |
| Regional names, such as “Japanese pearls” or “Mallorca pearls” | Cultured or imitation pearls, only with “cultured”, “imitation” or a similar word in front |
These rules come from sections 23.19 to 23.21 of the Guides.1 CIBJO’s standards follow the same principle: the unqualified word “pearl” means a natural pearl, and “pearl” must be preceded by “cultured” for cultured pearls, “composite” for composite pearls and “imitation” for imitations.4
Other pearl terms you may see#
- Blister pearl. A pearl that has grown onto the inner wall of the shell. CIBJO describes a cultured blister pearl as one attached to the shell by layers continuous with the shell’s own.4
- Mabe. An assembled cultured blister: a blister grown on purpose, cut from the shell, its bead removed, the space filled and the back covered with shell. Mabe is the common name.4
- Keshi. A cultured pearl with no bead, formed as a by-product of bead culturing; see keshi pearls. CIBJO says the word keshi should always be qualified as natural or cultured.4
- Seed pearl. Under US rules, a seed pearl is a natural pearl of about two millimeters or less.1
Questions people ask#
What is a seed pearl?
Under US rules, a seed pearl is a small natural pearl of about two millimeters or less. A cultured or imitation seed pearl must say so, as in "cultured seed pearl" or "imitation seed pearl".1
What are Oriental pearls?
In US jewelry guidance, "Oriental pearl" may only describe a natural saltwater pearl of the type traditionally obtained from mollusks of the Persian Gulf. The word "Oriental" may never be used for cultured or imitation pearls.1
Are Majorica pearls real pearls?
No. Majorica is a brand of imitation pearls made on the Spanish island of Majorca from a glass bead coated with "pearl essence". In the United States, a regional name such as "Mallorca pearls" must be preceded by a word such as "imitation" or "simulated".1 8
Is a shell pearl a real pearl?
No. A "shell pearl" is an imitation, a shell bead with an artificial coating. GIA's laboratory calls the name misleading and says imitation pearl is the proper name.9
What does "faux pearl" mean?
A faux pearl is an imitation pearl. Under US rules, terms such as "faux pearl" and "fashion pearl" must be preceded by "imitation", "artificial" or "simulated".1
References#
- U.S. Federal Trade Commission (Electronic Code of Federal Regulations). 16 CFR Part 23, Guides for the Jewelry, Precious Metals, and Pewter Industries. Source · Archived copy (accessed 2026-10-25)
- Gemological Institute of America (GIA), Birthstones. June Birthstones. Source · Archived copy (accessed 2026-10-25)
- Karan Rajguru, Anukul Belanke and Abeer Al-Alawi (2025). Imitation Seed Pearl with Blue X-Ray Fluorescence. Source · Archived copy (accessed 2026-10-26)
- CIBJO, The World Jewellery Confederation, Pearl Commission (2026). The CIBJO Pearl Book (Pearl Blue Book) 2026. Source · Archived copy (accessed 2026-10-25)
- Changbo Zhu, Paul C. Southgate and Ting Li (2019). Production of Pearls. Source · DOI 10.1007/978-3-319-96776-9_5 · Archived copy (accessed 2026-10-25)
- Gemological Institute of America (GIA), Gem Encyclopedia. Pearl Description. Source · Archived copy (accessed 2026-10-25)
- Fisheries Agency of Japan (水産庁) (2026). 真珠養殖をめぐる情勢について (On the situation of pearl culture). Source · Archived copy (accessed 2026-10-25)
- June Hanano, Mary Wildman and Philip G. Yurkiewicz (1990). Majorica Imitation Pearls. Source · DOI 10.5741/GEMS.26.3.178 · Archived copy (accessed 2026-10-25)
- Jessie Yixin Zhou and Chunhui Zhou (2014). Shell Pearl as a Pearl Imitation. Source · Archived copy (accessed 2026-10-26)
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- Unique Pearl, a pearl jeweler
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@misc{lap-basics-natural-cultured-and-imitation-pearls, title = {What Are Natural, Cultured and Imitation Pearls?}, author = {{Learn About Pearls editors}}, year = {2026}, howpublished = {\url{https://learnaboutpearls.com/basics/natural-cultured-and-imitation-pearls/}}, note = {Learn About Pearls, published by Unique Pearl}}
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