The Tahitian pearl harvest typically takes place between May and November. The normally the nucleators harvest their Tahitian pearls as well as nucleate them. At harvest, the nucleator makes an incision in the oyster’s gonad to remove the pearl. This is also part of the re-nucleation process. If the extracted pearl is round and of good quality, the nucleator will implant a new nucleus that is the same size as the newly extracted pearl into the opened pearl sac. The hope here is that the oyster, after it is re-nucleated with the larger nuclei, will produce a new pearl of equal or better quality that is much larger then the previous pearl.
On some pearl farms, if the extracted pearl is not round, the nucleator may glue a half-bead to the shell of the oyster, so that it may produce a blister pearl in the second cycle.
The resulting Blister Pearl oysters usually do not live past their harvesting time. Oysters that produce round Tahitian pearls twice in a row, however, are returned to the wild to live out their lives as egg or sperm producers. A Tahitian oyster can then live up to a very long 30 years. There are even other oysters that are nucleated a third and even a fourth time. The cultured Tahitian pearls produced by an oyster’s first harvest, when the oyster is younger and stronger, are generally of better quality than the second, third, and fourth harvests.
As much as 40% of the nucleated Tahitian oysters produce quality pearls of some kind of shape. These pearls are beautiful, but only 5% of the entire harvest will be round. Most of the shapes will be baroque or semi-baroque. In the end, only 1% to 2% of the pearl harvest will be round cultured pearls of the best quality. After they are harvested, a Tahitian pearl is washed in freshwater, dried, and lightly buffed by tumbling in a mixture of finely ground salt and bamboo chips. This is the only treatment done to Tahitian pearls by the pearl processors. Some additional treatments may be done after export for pearl jewelry, however.