The Tahitian Black Pearl -- Black Pearls From Tahiti

		OTHER  PEARLS  PRODUCED  IN  FRENCH  POLYNESIA             Besides the extremely rare natural fine black pearls and the   cultured pearls that we have discussed, there are four other kinds   of pearls that occur as a by-product of the pearl industry: KESHIS  |  BLISTER  |  MABE  |  PIPI KESHIS             These are small cultured pearls that result when only a   fragment of epithelial tissue is grafted.  Either the oyster rejects   the nucleus or the technician decides at the onset of the graph that   he wants to produce a keshis.  He then omits the nucleus   altogether, inserting only a piece of mantle in the pearl oyster. After   a year or two, the result is a small pearl, usually baroque in form,   displaying the same colors as natural or cultured pearls.   BLISTER             These can be either natural or cultured pearls whose core contains organic matter which decomposes, producing gas that causes the pearl to swell or blister. The result is a large baroque pearl, very light weight because it was inflated from the inside, and sometimes containing opaque black patches of organic origin. Blister pearls, which generally are steel-gray, formely were used as hatpins. Today jewelers use them to create original pieces. KESHIS  |  BLISTER  |  MABE  |  PIPI MABE             Half-pearls ---Another kind of cultured pearl produced by a different type of opperation on the Pinctada Margaritifera is called the half-pearl, reffered to as chicots (meaning "stump") in French or mabe in Japanese, from the name of the black-winged Pteria penguin oyster which yeilds only half-pearls. (By extension, the term mabe is used for all half-pearls. The technique for producing half-pearls is different from that used to make full pearls; it is also much simpler, which is the reason that half-pearls were obtained first in both Japan and Polynesia. To produce a half-pearl, the technician opens the oyster, gently pushes back the mantle and places a half-sphere (usually made of plastic) against the inner face of the shell, using a special glue to make it adhere. No graft is necessary. He then pulls the mantle back in place. At the end of a year, the foreign body is covered with a layer of nacre of the same color as the mother-of-pearl on the interior of the shell around the formation and, once it is cut out of the oyster, we have a half-pearl whose surface can be as smooth and varicolored as any black pearl. Half-pearls are much used in jewelry as pendants, rings and earrings. One can also produce two-third pearls by the same  technique. Generally older oysters are chosen for the production of half-pearls, whether or not those oysters have already been used to make full pearls. KESHIS  |  BLISTER  |  MABE  |  PIPI PIPI             Pipi  means "baby" in Tahitian, and we mustn't neglect to mention pipi pearls (pronounced "peepee"). These are small round, natural pearls which measure 3-4 millimeters in diameter and are yellow, orange, or honey colored. They are produced by the Pinctada Maculata oyster. These little pearl oysters are common in Polynesia, especially in closed lagoons. The pearls are harvested by letting the oysters rot in a basket enclosed by wire mesh. The basket is then washed in sea water and the pearls collected in a fine sieve.             The small number of pipi  pearls collected limits them to the local market, where there cost is reasonable and they are used to make nice delicate jewelry. It is to be hoped that their market value will not go up,  for unless the little oysters are raised by organized farming and systematically harvested, they will rapidly become extinct. For the time being, the limited market for pipi pearls wouldn"t appear to justify such efforts. (However, the first effort, perhaps, should be to find them a more poetic name.)