When nucleating Tahitian oysters, the way the oysters are handled must be cautious. The P. margaritifera oyster is ready for nucleation when it reaches about three years of age. Then they are taken out of the seawater for cleaning, sorting, and moving. They can only survive in the sun for about two hours and in the shade for about four hours. Fresh water, even rain, kills them quickly. Therefore one can imagine the cautious way one must prepare the Tahitian oyster.
When the oysters arrive at their nucleators, they are examined carefully. Only healthy specimens with fully developed gonads can be implanted with a sliver of mantle tissue and a bead nucleus. The nucleator must also choose a mantle-tissue donor that has to be a young and healthy Tahitian oyster with the desired mother of pearl shell color (green-black with purple highlights, for example). A strip of the deeply colored tissue is cut off the younger oyster with small surgical scissors, and placed on a surface that is wet with seawater. The nucleator then cuts this into approximately 3 mm squares. Each donor oyster gives enough mantle tissue for 40 implants. The shell color of the donor oyster will affect the color of the finished Black Tahitian pearls. Pearl necklaces in very dark green with peacock overtones will be highly prized.
The P. margaritifera oyster is about twice the size of the Akoya oyster when it is nucleated. The procedure however is still a very delicate one. Without patience, concentration, and knowledge of the oyster anatomy, the procedure could be a fatal one. The appropriate size bead size is chosen for the oyster based on the animal’s gonad size. The range is about 6mm to 10mm. The nucleator then carefully makes the small incision in the gonad and inserts the mantle tissue, as well as the bead. After the surgery, the incision is smoothed with the oyster’s own mucus. Finally the nucleator removes the wedge that kept the shell open and puts the oyster back in its tank. The procedure takes about two minutes, but it takes the oyster 20 to 30 days to heal.
As with the Akoya oyster, about 50% of the oysters die or reject the surgery. Therefore, this procedure is a long one which could all be for nothing if the proper care is not taken. The nucleators are very skilled workers, whose profession is not known by many. Any day someone gets a good harvest of Tahitian pearls is a good day for the pearl jewelry business.