The official definition of the Tahitian cultured pearl: The Tahitian cultured pearl is a natural coloured pearl, derived from grafting and breeding in the natural environment of French Polynesia, and which has not undergone any treatment (...). It is the raw product of the bio-mineralization process of the epithelial cells of a graft, a piece of mantle taken from a donor mollusc, of the genus Pinctada, originating in French Polynesia, around a nucleus. This support, with its specific characteristics, is inserted by humans into the pearl pouch (gonad) of the Pinctada margaritifera cumingii variety pearl oyster. (Law of the country n° 2017-16 of 18 July 2017.)
Wonders of French Polynesia
The formation of a Tahitian pearl requires time and work. But these efforts are well worth it! The most important work is done by the pearl oyster itself, which will protect itself from a foreign body by secreting mother-of-pearl. And mother-of-pearl is what makes the essence of the pearl, giving it its shade, lustre and durability.
If the natural pearl has been known to humans for a long time, it was at the beginning of the twentieth century that the culture of the pearl, a technique invented and perfected by the Japanese before being exported to the Pacific. Pearl culture involves the insertion into the reproductive organ of an oyster from a nucleus, a mother-of-pearl bead, and a graft, a piece of tissue from another oyster. And if everything goes well afterwards, a pearl will be formed by the oyster and then harvested after about 2 years of breeding.
At Mihiarii Pearls, all pearls sold are authentic Tahitian pearls, corresponding to the official description you find below. When shopping, do not hesitate to ask us for a certificate of authenticity.
Classification of Tahitian pearls
You certainly want a perfect pearl, without imperfection and very bright. This is the highest quality in the classification system used in French Polynesia. But the higher the quality of a pearl, the rarer it is and the more expensive it is. In addition, very beautiful pearls can be found in the lower qualities. Our craftsmen can also make sure that any imperfections are masked as much as possible, especially during drilling.
The official classification system takes into account the quality of the pearl's surface and its luster (Order No. 1258 of the Council of Ministers of 31 July 2017). A flawless surface is a completely smooth surface. Imperfections on the surface can be punctures, furrows or bumps for example. An excellent luster corresponds to a very bright pearl or more precisely to a total reflection of light, i. e. a mirror effect. A low gloss corresponds to a matt, low gloss pearl.
Here are the different categories defined by French Polynesia:
- perfect category (TOP GEM): pearl without imperfection with an excellent luster;
- category A: pearl with some concentrated slight imperfections with a very good luster at least;
- category B: pearl with slight imperfections in greater quantity but with a large clean surface and a good luster at least;
- category C: pearl with obvious slight and deep imperfections but with a relatively clean surface and an average luster at least;
- category D: pearl with slight and deep imperfections on a large surface with a low luster at least;
- category E: pearl not falling into the categories listed above.
Before the country law of 18 July 2017, category E did not exist. Pearls in this category were considered as scrap and could not be exported. They were destroyed during the controls in the Cultured Pearl Department of French Polynesia. This is no longer the case today. Similarly, during pre-export checks, the pearls were examined by X-ray. Pearls with a mother-of-pearl layer of less than 0.8mm were also destroyed. This provision has not been renewed.
Another pearl classification system is sometimes used, that of the Gemological Institute of America (GIA) called the AAA-A system. The AAA quality is more or less equivalent to the A quality of the Tahiti system while the A and AA qualities would correspond to the C quality of the Tahiti system. Not to be confused! At Mihiarii Pearls, we do not use this system. A pearl of quality A in our shops, corresponds to a pearl of very good quality.
Shape of Tahitian pearls
If the round shape is the most popular, the Tahitian pearl comes in several shapes, each with its own charm. Here are the shapes you can find in our Mihiarii Pearls stores, grouped into three main categories:
- Symmetrical spheres:
- Round (R): The most sought-after but also the most expensive pearls;
- Semi-round (SR): Slightly flattened or elongated. During assembly, the SR pearls may appear perfectly round.
- Symmetrical:
- Drops / Pears (DR): One end is wider than the other. A shape that fits very well with pendants and earrings.
- Ovals (OV): Narrower at the ends than in the centre.
- Buttons (BT): Flattened on one or both sides. The Buttons pearls fit well with earrings.
- Semi-baroque (SB): Other shapes, not round, but with an axis of symmetry.
- Asymmetrical:
- Baroque (BA): Without specific forms. Can be used to make a beautiful necklace or a truly original bracelet.
The pearls of these different shapes may have one or more beads or grooves around their surface. These pearls are then called circled pearls.
Colors of Tahitian pearls
From black or dark pearls to creamy tones, from intense green to deep blue, Tahitian pearls have a wide range of colours to suit all tastes. Some colours are rarer than others, which has an impact on the final price of the pearl.
The main color
Each pearl has a basic color that must be as homogeneous as possible. These colours can be for example aubergine, blue, green, grey or champagne. They can be combined with each other, giving blue-green, eggplant grey.... They can also be dark, medium or light. The colour palette is therefore very wide.
Secondary colors (or lines)
One or more secondary colors may appear above the main color. For example, a grey pearl may have pink or green shades.
The iridescence (or orient)
The surface of some pearls have a particular property. Shades of colour seem to float on the surface of the pearl as it is rotated or the brightness changes.
Peacock type pearls are very popular. These pearls have a main color gray-green with pink, aubergine or golden iridescences.
Other classification criteria
The size
The size of Tahitian pearls is measured in millimeters, usually rounded down to the nearest unit. For example, we will talk about 8mm pearls or size 8.
The average size, the most common, is between 8 and 10mm. Below 8mm is quite rare in our shops. Pearls between 10 and 12mm are quite common. However, for the same price, a 12mm pearl will have a lower quality than an 8mm pearl, large pearl still being rarer. Finally, above 12mm, pearls can reach stratospheric prices. A 16mm round pearl of quality D, can exceed a thousand euros, while a B quality pearl of the same size can approach ten thousand euros. (The price will also depend on the color, iridescence or shape.) But you don't have to reach these rates to enjoy yourself.
The thickness of the mother-of-pearl layer
It is possible to measure the thickness of the mother-of-pearl layer by examining the beads with X-rays. Formerly mandatory for exports, this examination has become optional and subject to a fee. It can be made on request by the Pearl Culture Department of French Polynesia.
Pairing or assortment
The appearance or assortment is a long and meticulous work. It is necessary to find pearls with matching colors and very close sizes. An acceptable size difference is approximately between 0.1 and 0.2mm, beyond which the difference could be visible. Mihiarii Pearls offers pairings for earrings as well as assortments of pearls for necklaces. Take advantage of our know-how.