--- title: "How Can You Tell If Pearls Are Real?" description: "How to tell real pearls from imitations: what the surface, the drill hole and the tooth test can show, what they can't prove, and what a gem lab adds." canonical_url: "https://learnaboutpearls.com/identification/how-to-tell-if-pearls-are-real/" last_updated: "2026-11-04" last_reviewed: "2026-10-26" reviewed_by: "Simon" publisher: "Unique Pearl" publisher_disclosure: "Learn About Pearls is published by Unique Pearl, a pearl jeweler." --- # How Can You Tell If Pearls Are Real? **Short answer:** Look closely, then feel. Under magnification, real pearls show overlapping platelets of nacre, while imitations often show a glittery coating that can chip or peel near the drill hole. In the tooth test, the cultured pearls in a GIA study felt gritty and the imitations smooth. But good imitations can match real pearls in look and weight, and only a laboratory can tell a natural pearl from a cultured one. **Key facts:** - GIA researchers found four tests conclusive for separating a widely sold imitation from cultured pearls, namely refractive index, magnification, X-radiography and the tooth test. [1] - In the tooth test, the cultured pearls felt gritty and the imitations smooth. [1] - Imitations lack nacre's overlapping platelets, and often show a glittery coating and sometimes molded drill holes. [2] - Coated shell-bead imitations can match cultured pearls in appearance and heft. [3] - At the drill hole, a cultured pearl shows a thin, often dark layer between the bead and the nacre, and sharp edges. The imitations GIA studied showed no such layer, and ragged edges. [1] - In 2025, GIA reported finding a single imitation among about 9,360 pearls in 18 strands. [2] The first question about any pearl is whether it is a pearl at all, natural or cultured, or an [imitation pearl](https://learnaboutpearls.com/glossary/#imitation-pearl). Some simple checks can point to an imitation, but each one has limits. ## Look at the surface Real pearls are made of [nacre](https://learnaboutpearls.com/glossary/#nacre), which under magnification shows overlapping platelets. Imitations lack them. GIA describes imitations as often showing a glittery surface from their [coating](https://learnaboutpearls.com/glossary/#coating) material, and sometimes molded drill holes. [2] In one group of shell-bead imitations, magnification showed many tiny glittering particles instead of nacre platelets. [3] A look that is too perfect can be a clue as well. In GIA’s study of Majorica imitations, strong iridescence on a smooth surface, together with a very high [luster](https://learnaboutpearls.com/glossary/#luster), pointed to an imitation; on [cultured pearls](https://learnaboutpearls.com/glossary/#cultured-pearl), that kind of iridescence was more common on irregular surfaces. Most other imitations of the time, made by dipping or painting beads in resin, showed no iridescence at all. [1] ## Look at the drill hole The drill hole shows what is inside. Under 10× magnification, a cultured pearl shows a thin, often dark layer of [conchiolin](https://learnaboutpearls.com/glossary/#conchiolin) between the [shell bead](https://learnaboutpearls.com/glossary/#bead) and the nacre, and the edges of the hole are sharp and well defined. [1] The imitations GIA examined had no such layer, and ragged edges. [1] Cultured pearl - A thin dark layer between bead and nacre - Sharp, clean edges at the hole Imitation - A bead with only a thin coating - Ragged coating at the hole What a loupe shows at the drill hole. Drawn for Learn About Pearls; not to scale. **Text version of this diagram** The drawing shows two beads cut through the drill hole. The cultured pearl has a shell bead in the middle, a thin dark ring around the bead, and rings of nacre outside it; the hole runs straight through with clean, straight edges. The imitation is a plain glass bead with only a thin colored coating on the outside; where the hole passes through the coating, the coating’s edges are drawn ragged. Coatings can chip and peel near the hole. On some shell-bead imitations, the damage exposed the white shell underneath. [3] An unusually large drill hole can be a warning sign too. [2] ## The tooth test In GIA’s study, the [tooth test](https://learnaboutpearls.com/glossary/#tooth-test) was one of four conclusive tests: the cultured pearls felt gritty against the teeth and the imitations felt smooth. [1] The test has limits. [Natural pearls](https://learnaboutpearls.com/glossary/#natural-pearl) share most surface characteristics with cultured pearls, [1] so the tooth test can’t tell them apart. ## Weight and other quick checks Weight isn’t a reliable guide. GIA found coated shell-bead imitations similar in heft to cultured pearls. [3] Avoid any test that damages a pearl. A dilute hydrochloric acid solution makes a cultured pearl effervesce, [1] and CIBJO says pearls should be kept away from all acids. [4] ## What a laboratory can tell you A gem laboratory settles the question. In GIA’s study, the imitations had a significantly lower spot refractive index than cultured pearls, and on X-ray they appeared opaque, without the contrast between bead and nacre that a cultured pearl shows. [1] X-ray imaging also separates natural from cultured pearls: a natural pearl shows no bead or curved cavity at its center. [5] [Laboratory reports](https://learnaboutpearls.com/glossary/#laboratory-report) state whether a pearl is natural or cultured, and SSEF’s reports also indicate treatments. [6] Imitations can still surprise a lab. In 2025, GIA’s Mumbai laboratory found one imitation among about 9,360 pearls in 18 strands. [2] It looked like the pearls around it, and its X-ray image even showed arcs like the growth arcs of the natural pearls beside it, but other tests showed it was not a pearl. [2] The page [real vs imitation pearls](https://learnaboutpearls.com/compare/real-vs-imitation-pearls/) explains what imitations are made of, and the [“are my pearls real?” checklist](https://learnaboutpearls.com/tools/are-my-pearls-real/) takes you through the checks one by one. ## Questions people ask ### Does the tooth test really work on pearls? As a first check against imitations, yes. In a GIA study, cultured pearls felt gritty and imitations smooth, and the tooth test was one of four tests that separated them reliably. It can't tell a natural pearl from a cultured one, though; that takes a laboratory. [1, 6] ### Are heavier pearls more likely to be real? Not reliably. GIA found that imitations made of coated shell beads were similar in heft to cultured pearls. [3] ### Can real and imitation pearls be mixed in one strand? Yes. In 2025, GIA found one imitation among about 9,360 pearls in 18 strands. It looked like the others, but its very large drill hole raised suspicion, and further tests showed it was not a pearl. [2] ### How can I tell if my pearls are natural or cultured? Only a gem laboratory can tell, mainly with X-ray imaging of the inside of the pearl. A natural pearl shows no bead or curved cavity at its center, and a uniform, onion-like structure. [5, 7] ### Is an acid test a good idea? No. Acid attacks pearls. In GIA's tests, a dilute hydrochloric acid solution made a cultured pearl effervesce, and CIBJO says pearls should be kept away from all acids. [1, 4] ## References 1. June Hanano, Mary Wildman and Philip G. Yurkiewicz (1990). Majorica Imitation Pearls. [Source](https://www.gia.edu/doc/Majorica-Imitation-Pearls.pdf) · DOI [10.5741/GEMS.26.3.178](https://doi.org/10.5741/GEMS.26.3.178) · [Archived copy](https://web.archive.org/web/20251005124434/https://www.gia.edu/doc/Majorica-Imitation-Pearls.pdf) 2. Karan Rajguru, Anukul Belanke and Abeer Al-Alawi (2025). Imitation Seed Pearl with Blue X-Ray Fluorescence. [Source](https://www.gia.edu/gems-gemology/summer-2025-lab-notes-imitation-seed-pearl) · [Archived copy](https://web.archive.org/web/20261102191034/https://www.gia.edu/gems-gemology/summer-2025-lab-notes-imitation-seed-pearl) 3. Jessie Yixin Zhou and Chunhui Zhou (2014). Shell Pearl as a Pearl Imitation. [Source](https://www.gia.edu/gems-gemology/summer-2014-labnotes-shell-pearl) · [Archived copy](https://web.archive.org/web/20260513190053/https://www.gia.edu/gems-gemology/summer-2014-labnotes-shell-pearl) 4. CIBJO, The World Jewellery Confederation, Pearl Commission (2026). The CIBJO Pearl Book (Pearl Blue Book) 2026. [Source](https://cibjo.org/wp-content/uploads/2026/10/Pearl-Blue-Book-2026-.pdf) · [Archived copy](https://web.archive.org/web/20261025235254/https://cibjo.org/wp-content/uploads/2026/10/Pearl-Blue-Book-2026-.pdf) 5. Changbo Zhu, Paul C. Southgate and Ting Li (2019). Production of Pearls. [Source](https://link.springer.com/chapter/10.1007/978-3-319-96776-9_5) · DOI [10.1007/978-3-319-96776-9_5](https://doi.org/10.1007/978-3-319-96776-9_5) · [Archived copy](https://web.archive.org/web/20240129152149/https://link.springer.com/chapter/10.1007/978-3-319-96776-9_5) 6. Swiss Gemmological Institute SSEF. Pearls (SSEF reports). [Source](https://www.ssef.ch/reports/pearls/) · [Archived copy](https://web.archive.org/web/20260611191437/https://www.ssef.ch/reports/pearls/) 7. Chunhui Zhou and W. Henry Towbin (2024). Applications of X-Ray Radiography and X-Ray Computed Microtomography in Gemology. [Source](https://www.gia.edu/gems-gemology/winter-2024-x-ray-imaging) · DOI [10.5741/GEMS.60.4.582](https://doi.org/10.5741/GEMS.60.4.582) · [Archived copy](https://web.archive.org/web/20260313113455/https://www.gia.edu/gems-gemology/winter-2024-x-ray-imaging) **Written by:** Learn About Pearls editors **Fact-checked:** Learn About Pearls editors, October 26, 2026 **Reviewed by:** Simon, October 26, 2026 **First published:** November 4, 2026 **Publisher:** [Unique Pearl](https://learnaboutpearls.com/about/), a pearl jeweler **Revision history** 1. November 4, 2026: First published. First published **How to cite this page** **APA:** Learn About Pearls editors. (2026). _How Can You Tell If Pearls Are Real?_ Learn About Pearls. https://learnaboutpearls.com/identification/how-to-tell-if-pearls-are-real/ **MLA:** “How Can You Tell If Pearls Are Real?” _Learn About Pearls_, Unique Pearl, November 4, 2026, learnaboutpearls.com/identification/how-to-tell-if-pearls-are-real/. **Chicago:** Learn About Pearls editors. “How Can You Tell If Pearls Are Real?” Learn About Pearls. Unique Pearl. Last modified November 4, 2026. https://learnaboutpearls.com/identification/how-to-tell-if-pearls-are-real/. **BibTeX:** `@misc{lap-identification-how-to-tell-if-pearls-are-real, title = {How Can You Tell If Pearls Are Real?}, author = {{Learn About Pearls editors}}, year = {2026}, howpublished = {\url{https://learnaboutpearls.com/identification/how-to-tell-if-pearls-are-real/}}, note = {Learn About Pearls, published by Unique Pearl}}` Quoting with attribution and a link is welcome. See [how to cite and reuse](https://learnaboutpearls.com/cite/). **Suggest a correction** ## Related pages - [Real vs imitation](https://learnaboutpearls.com/compare/real-vs-imitation-pearls/): How pearls grown by mollusks differ from manufactured imitations, and how to tell them apart. - [Dyed and treated pearls](https://learnaboutpearls.com/identification/dyed-and-treated-pearls/): The common pearl treatments, from bleaching and dyeing to irradiation, and how labs detect them. - [Natural, cultured and imitation](https://learnaboutpearls.com/basics/natural-cultured-and-imitation-pearls/): What the words natural, cultured and imitation mean on a pearl, and the rules for using them.