The making of a pearl

Tahitian pearl farming can produce black pearls which mean the marine cultured pearls produced from the black lip pearl oyster shell, Pinctada margaritifera, and they are abundant in the atolls of French Polynesia.

These pearls, have a wide range of natural colours, from white to dark and all shades of grey, and are the only cultured pearls in the world with so many different natural colours as the famous green rose peacock.

The technique to produce marine cultured pearls was developed in Japan and, except for some minor details, is similar in French Polynesia. A mother of pearl bead is inserted in the animal together with a piece of tissue (mantle) taken from another pearl oyster.

The piece of tissue, as a graft tissue, will develop quickly and will form a skin around the bead and then will deposit mother of pearl on the surface of the bead. Bead rejection is important and concerns about 30 percent of the seeded shells, mainly because the graft tissue is not close enough to the bead. Even with perfectly round beads, only 20 percent of the pearls will be perfectly round at the harvest which is about two years after the seeding.