Tahitian pearls are cultured pearls grown in the black-lip pearl oyster, Pinctada margaritifera, mostly in the lagoons of French Polynesia. They are the only cultured saltwater pearls that come out of the oyster in naturally dark colors, from silver and gray to deep green, blue, purple and near-black. Few of them come from the island of Tahiti itself. The name comes from the territory's best-known island and its trading center, Papeete.
The black-lip oyster
Pinctada margaritifera is a large oyster, smaller than the South Sea Pinctada maxima but much bigger than the Akoya. The inner rim of its shell has a band of dark nacre, which gives it the name black-lip. When technicians graft tissue from this dark-edged mantle, the pearl sac lays down dark nacre and the pearl takes on the same colors.
The species lives across a wide stretch of the tropical Indo-Pacific. In French Polynesia, a variety often called Pinctada margaritifera cumingi fills the lagoons of the coral atolls. The Cook Islands, especially Manihiki and Penrhyn, also farm black-lip oysters on a smaller scale. Pearls from these islands look similar but come from a different country.
Natural pearls and shell before farming
The Polynesians used black-lip shell for tools, fish hooks and ornaments long before Europeans arrived. In the 19th century, European and American traders bought large amounts of mother-of-pearl shell from the Tuamotu atolls, and divers occasionally found natural black pearls. Overharvesting depleted many lagoons. Colonial authorities set rules on diving seasons and closed lagoons in rotation to let stocks recover. The page on natural pearls covers wild pearl fisheries more broadly, and mother-of-pearl covers the shell itself.
The start of pearl culture
Experiments with culturing black-lip oysters in French Polynesia began in the early 1960s, with help from Japanese technicians. The first successful cultured black pearls came from trials in the Tuamotu atolls during that decade, and private farms followed. Commercial production grew quickly in the 1970s and 1980s. The cultured pearl industry became one of French Polynesia's most important sources of export income in the late 20th century, along with tourism.
The farms are spread across the Tuamotu Archipelago and the Gambier Islands, in clear, calm atoll lagoons. Many farms are small family businesses on remote atolls. Larger companies run bigger operations, and some produce their own oysters.
How Tahitian pearls are grown
Tahitian farms use the bead nucleation method described on the cultured pearls page:
- Farmers collect young oysters as spat on lines or mesh set out in the lagoon, then grow them for about two years.
- A technician places a shell bead and a small square of mantle tissue from a carefully chosen donor oyster into the gonad.
- The oysters hang on lines in the lagoon, where workers clean them of growth such as algae and barnacles.
- After roughly 18 months to two years, farmers harvest the pearls.
- An oyster that produced a good pearl may be nucleated again with a larger bead in the same sac.
Donor choice matters a great deal. The color of the donor's nacre strongly affects the color of the finished pearl, so technicians select donors to aim for particular shades.
Colors and overtones
Tahitian pearls are often called black pearls, but true jet black is uncommon. Most have a dark gray to charcoal body color, and many show colored overtones on top. Common trade terms include:
- Peacock: a dark green body with rose or purple overtones, often the most sought after.
- Aubergine: a purple to eggplant shade.
- Pistachio: a yellowish green.
- Silver and light gray: pale pearls that still show the black-lip nacre.
- Blue, green and cherry: named for the dominant overtone.
The colors come from organic pigments in the nacre and its layered structure. The page on what pearls are made of explains overtone and orient, and the color in gemstones page covers pigments in other gems. Dark Akoya and freshwater pearls are usually dyed or irradiated to look like Tahitian pearls. A lab can tell these apart.
Size and shape
Tahitian pearls typically measure about 8 to 15 mm, with larger pearls rare. Round pearls make up only a small part of each harvest. Circled pearls, with one or more grooves running around the pearl, are very common in Tahitian harvests and cost less. Drops, ovals, buttons and baroques are also common and popular for earrings and pendants.
Quality regulation
French Polynesia regulated its pearl exports more tightly than most producing regions, in an effort to protect prices and reputation after a period of oversupply in the 1990s. Under rules in force from the early 2000s, pearls had to pass a government quality check before export. The rules included:
- A minimum nacre thickness of 0.8 mm, checked by X-ray.
- Classification on an A to D scale based on surface quality and luster.
- A ban on exporting pearls below grade D or with thin nacre. Rejected pearls were destroyed.
The pearl grading page explains the A to D categories. The government reformed the system in the late 2010s and dropped compulsory grading of every pearl. Buyers should still rely on actual inspection or a lab report and not assume a pearl passed a particular check.
Tahitian compared with South Sea pearls
| Feature | Tahitian | South Sea |
|---|---|---|
| Oyster | Black-lip, Pinctada margaritifera | Gold-lip and silver-lip, Pinctada maxima |
| Main producer | French Polynesia | Australia, Indonesia, Philippines |
| Natural colors | Gray, green, blue, purple, near-black | White, silver, cream, gold |
| Typical size | About 8 to 15 mm | About 9 to 16 mm |
The South Sea pearl farming page covers the white and golden pearls, and the pearls overview compares all four main types.
The guide to cleaning jewelry safely has more detail on soft gems.
Frequently asked questions
Are Tahitian pearls naturally black?
Yes. Their dark colors come from the black-lip oyster's nacre, not from dye. Very dark Akoya or freshwater pearls, by contrast, are usually dyed or irradiated.
Do all Tahitian pearls come from Tahiti?
No. Most come from farms on the Tuamotu and Gambier atolls of French Polynesia. Tahiti is the main island and trading hub, which is where the name comes from.
What is a peacock Tahitian pearl?
Peacock describes a dark green to gray body color with rose or purple overtones. It is one of the most popular Tahitian colors.
Why are so many Tahitian pearls circled?
Circled pearls are very common in black-lip oysters, and the grooves are thought to relate to how the pearl turns in its sac as nacre forms. They cost less than round pearls but are popular for their distinctive look.