Commonly known around the world as black pearls, the pearls of Tahiti are indigenous to the remote lagoons of French Polynesia in the South Pacific.

Legend has it that the pearl oyster, Te Ufi was offered to man by Oro, the god of peace and fertility, who came down to earth on a rainbow. Some say that Oro offered the pearl front this oyster to the beautiful princess of Bora Bora as a sign of his eternal love. 

The scientific term for Te Ufi left is Pinctada margaritifera, most commonly known as the black lipped oyster. In the 19th century, its shell, like that of many oysters, was in great demand by the European button industry. As a result, commercial shell harvesting operations by local and foreign entities took place annually in the lagoons of Tuamotu and Gambier, two of the five archipelagoes that make up French Polynesia.

In the days of such lucrative shell harvesting, one would have to open more than 15,000 oysters before finding a natural pearl. 

So even before the secret of pearl cultivation was discovered, the Tahitian pearl had earned a reputation for value and rarity. This reputation was further enhanced by its use in the jewelry of the world's royalty and nobility. Soon the Tahitian pearl became known as the "pearl of queens and queen of pearls".

The most famous of these natural black pearls was called "Azra". It was the centerpiece of a necklace that was part of the Russian crown jewels. 

Today, the Tahitian pearl has become an exotic gem sought after by celebrities and pearl aficionados alike. 

The Pearl Culturing Industry

In 1961 the first culturing experiments took place in the lagoon of Bora Bora. The harvest of 1963 proved conclusively, that a pearl culturing industry in the region was possible. As a result of the success on Bora Bora, several pearl farms were set up on the islands of Manihi, Marutea and Mangareva to increase French Polynesia's pearl production.

The process of raising a pearl oyster is a long one and requires considerable care and attention due to the fragility of the oyster species.

At certain times of the year the black-lipped pearl oyster, which lives attached to coral found in Polynesia lagoons, produces spawn that is then fertilized in the water. After floating freely for a month, the baby oysters, known as "spat", either fix themselves to the coral or perish buried in the sand. 

The pearl farmers collects the spat by submerging artificial collectors in the lagoon. They are then reared on underwater lines for more than three years. During this time, the oysters are meticulously cared for to ensure their health and vitality. 

When the oyster reaches maturity it is ready for grafting or nucleation, whereby a small, round piece of mother-of-pearl (called a nucleus) is surgically inserted into the body of the oyster. The introduction of this nucleus stimulates the secretion of a pearly substance called "nacre", which is applied in layers by the oyster to the nucleus.

After several years of nacre secretion over the nucleus a pearl is formed. The pearl is then carefully removed and the oyster put back in the lagoon to recuperate. Although the process sounds simple, the delicate nature of this species of oyster means that of every hundred oysters nucleated, only thirty will produce pearls. Out of these thirty pearls, only one or two will be perfect gems. 

The Quality of Tahitian Pearls

A Tahitian cultured pearl consists of thick pearly layers containing organic substances and calcium carbonate in the form of aragonite. Most commonly, these layers are referred to as nacre.

Tahitian cultured pearls are best known for their diversity of size, shape, quality and many shades of natural colors, ranging front pale gray to anthracite black.

The trade designation "Tahitian cultured pearl" is reserved exclusively for cultured pearls obtained front the Pinctada margaritifera pearl oyster, found in French Polynesia. According to government accord, such pearls must exhibit a continuous pearly layer over at least 80% of the pearl surface and cannot reveal the underlying nucleus.

Any pearls that do not satisfy these criteria may not be called a "Tahitian cultured pearl" and be deemed a reject. Reject pearls are best described as calcite pearls, organic pearls and pearls whose nucleus is visible to the naked eye. 

Tahitian Pearls Classification

When harvesting pearls, the farmer performs an initial sort of-this crop, discarding all the rejects. He then performs a more detailed separation of his crop sorting out pearls by size, shape and quality.

Size

Pearls are most commonly expressed in millimeters. Tahitian cultured pearls generally range in size from 8 mm to 16 mm.

Shape

There are four basic shapes that Tahitian cultured pearls come in:

	Round and Semi Round Round pearls are almost-perfect spheres whose diameter variation rate is less than 2 %. Semi round pearls are slightly imperfect spheres whose diameter variation rate is greater than 2 % but less than 5 %.
	Semi-Baroque Semi-baroque exhibits at least one axis of rotation and are subdivided into drop, button, and oval shapes.
	Baroque Baroque pearls do not have any axis of rotation and are asymmetrical in shape.
	Circled Circled or ringed pearls are characterized by regular streaks or concave rings, perpendicular to an axis of rotation over more than one third of the pearl's surface.

Q U A L I T Y

This is determined by observing the special features of the pearl's surface and luster. Special surface features are considered to be any flaw in the nacre that is visible to the naked eye such as pits, bumps, scratches, deposits, ridges and cracks.

Luster is evaluated according to reflection of light on the pearl's surface. The brighter the reflection, the higher the luster.

Tahitian cultured pearls are defined by four basic qualities: A, B, C, D.

	Quality A  An "A Quality" pearl is one that has no surface flaws or very slight flaws that are visible to the naked eye and confined to less than 10% of its surface. All "A Quality" pearls exhibit a very high luster.
	Quality B A "B Quality" pearl is one that exhibits high or medium luster with some flaws visible to the naked eye and distributed over less than one third of the surface.
	Quality C A "C Quality" pearl is one that exhibits several visible flaws, distributed over more than one third of the surface and exhibits a medium quality luster.
	Quality D A "D Quality," pearl is one that exhibits a large amount of visible flaws over more than two thirds of the surface, regardless of luster.

The Quality of Tahitian Pearls

At the producers' stage, quality evaluation is based solely on size, shape and quality. However, when Tahitian cultured pearls enter the wholesale trade pipeline further evaluation and pricing will be based on the demand of the consumer, the rarity of the size, shape and color of the pearl and the final destination of the pearl.

Generally large, rounder pearls which exhibit a high luster with few flaws will still command the most premium prices. In addition, special pearl colors such as peacock, aubergine and pistachio will carry a premium price because of their rarity.

A Range of Products

Due to the wide range of iridescent colors and unusual shapes of Tahitian cultured pearls, one can find a vast array jewelry styles employing these fine gems. From trendy, "cutting edge" designs to classic "haute joaillerie", the unique nature of Tahitian pearls makes them adaptable to a myriad of jewelry design concepts. 

This gem's fairly large size provides a visibility and presence that most other precious stones or other types of pearls cannot provide within the same price range.