- Round and semi -round
- Semi-baroque pearls (subdivided into Drop, Button and Oval shapes)
- Baroque pearls, which do not have any axis of rotation and are asymmetrical in shape
- Circled pearls or ringed pearls, characterized by regular streaks or concave rings, perpendicular to an axis of rotation, over more than one third of the pearl's surface.
Quality 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 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.
The AAA-A System grades pearls on a scale from AAA to A, with AAA being the highest grade. This grading scale is common to freshwater and akoya pearls only, but is accepted by many with South Sea and Tahitian pearls as well:
Quality AAA: The highest-quality pearl, virtually flawless. The surface will have a very high luster, and at least 95% of the surface will be free from any type of defect.
Quality AA: The surface will have a very high luster, and at least 75% of the surface will be free from any type of defect.
Quality A: This is the lowest jewelry-grade pearl, with a lower luster and/or more than 25% of the surface showing defects. In many cases, if the pearl is being mounted into a piece of jewelry, it can be mounted so that the defects are hidden -- thus providing a lovely jewelry piece at a lower price.
The A-D System (or Tahitian System) grades pearls on a scale from A to D, with A being the highest grade. This is the system used in French Polynesia (based on a government standard there) to grade Tahitian pearls, and South Sea pearls only. It is therefore sometimes referred to as the "Tahitian system." While this system is standard in producing countries, other markets will still utilize AAA-A.
Quality A: Has no surface flaws or very slights flaws that are visible to the naked eye and confined to less than 10% if its surface. All "A Quality" pearls exhibit a very high luster.
Quality B: 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: Exhibits several visible flaws, distributed over more than one third of the surface and exhibits a medium quality luster.
Quality D: Exhibits a large amount of visible flaws over more than two thirds of the surface regardless of luster.
At the producers' stage, quality evaluation is based solely on size, shape and quality. However, when Tahitian cultured pearls enter the wholesale trade, evaluation and pricing becomes 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 (green overtone), aubergine (rose/mauve overtone) and pistachio (mauve overtone) will carry a premium price because of their rarity.
All cultured pearls have different variances of colors, sizes and shapes that make them unique.
Production of the Pearl
A Tahitian cultured pearl consists of thick pearly layers containing organic substances and calcium carbonate in the form of aragonite we most commonly call "nacre.'
The trade designation, "Tahitian Cultured pearl," is reserved exclusively for cultured pearls obtained from the Pinctada Margaritifera pearl oyster, found in the lagoon of the atolls of French Polynesia. According from the governmental department responsible for the pearl quality control, called "Service de la Perliculture" meaning Pearl Farming Department, such pearls must exhibit a continuous pearly layer over at least 80 % of the pearl surface and cannot reveal the underlying nucleous.
Any pearls that do not satisfy these criteria may not be called a "Tahitian Cultured pearl" and will be deemed a reject. Reject pearls are best described as calcite pearls, organic pearls and pearls whose nucleus is visible to the naked eye. Those rejects will be destroyed to avoid illegal distribution into the pearl market.
Raising a pearl oyster is a long process and requires considerable care and attention due to the fragility of the oyster species.
From every hundred oysters nucleated, only thirty will produce pearls. Out of these thirty pearls, only one or two will be perfect gems (quality A, B)
Culture of the Pearl
The pearl farm collects the spat or baby oysters from the fertilization of the black-lipped pearl oyster called also" Pinctada Margaritifera". They are placed on 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 they reach maturity, they are ready for grafting or also nucleation. This procedure consists to perform a surgical insertion of a small, round shell found in Mississippi River in United States 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 until the next grafting.
Manna Tahiti Black Tahitian Pearl jewelry offers exquisite pearl jewelry designs for every man. Know more about the Black Tahitian cultured pearl classification, size, shape, quality and production process by visiting the links we have listed below for your convenience.
Service de la Perliculture: Pearl farming official department in French Polynesia
Pearl-guide.com: The World Largest Pearl Information source