Years ago, I learned about the black pearls of Tahiti, and I have been interested in them ever since. On our 25th wedding anniversary, my husband and I went to Hawaii, and he bought me a black pearl pendant. That was two decades ago; now, I am on Huahine in the South Pacific, headed out in the lagoon, riding in an outrigger canoe with a small attached outboard motor, to visit a black pearl farm. It is here, under the calm waters of the sheltered lagoon, that the world’s famous black pearls are naturally grown.
In the middle of the Pacific Ocean, south of the Equator, are scattered pearl islands, built by lava and coral. A coral barrier encloses the fragile lagoons. The more recent the island, the smaller the lagoon, and the older the island, the bigger the lagoon; after millions of years, the volcanic island will disappear under the sea and the coral barrier, called an atoll, will grow.
While in the outrigger canoe, I could see in the distance a tiny building, out in the water, built on stilts called a “fare greffe.” It didn’t take long before I was standing under the straw roof of the structure, where the black pearls are brought up from under the water.
I learned the history and many facts about producing black pearls. The black pearl is inside of a large oyster (nacre). All oysters do not produce pearls, but many bivalves do, including the white pearls of Japan. Pinctada margitifera is the large oyster that produces the black pearl of Tahiti. An adult nacre can live up to 30 years. The black pearl nacre can attain a diameter of 30 cm and weigh 5 kilos. To grow, it must live within the calm waters of a lagoon. When a nacre is two or three years old, it will begin to produce eggs and over a lifetime, it will lay over a million eggs. Most eggs never survive. Those that do grow into larvae, which are prey for animals feeding on plankton. Then the young still left are prey to triggerfish. Fragile pinctada margaritifera need constant care to survive.
There is a slight difference between a fine pearl and a cultured pearl. Both are natural pearls produced by a bivalve, and with both nacres, a foreign particle such as a piece of sand enters the tissues of the nacre. This bothers the nacre, which reacts by secreting a thin coat of aragonite around the intruder and keeping it in constant rotation. After a time, it becomes isolated, with layers of this secretion forming a pearl. The difference with the cultured pearl is that the foreign particle is surgically implanted by a human and the nucleus is a tiny bead. Under an x-ray the difference can be determined. The fine pearl has nearly disappeared from the world market.
During the first colonization of the Polynesian Islands, there were pearl divers. The natives used black pearls for buttons and ornaments as well as jewelry. It was so popular in the early nineteenth century that empty sharp shells covered the shallow waters of the beaches. As the fine black pearls became more difficult to find, the divers had to dive in deeper water which became dangerous work because of moray eels, sharks, and pressure to the brain from diving too deep. Later the black pearl trade was overgrown, and the local government put heavy bans on the black pearl industry, limiting it entirely to cultured pearls and only a select few pearl farms. The first cultured pearl was harvested in 1893 in Japan, and a more successful grafting technique was invented there in 1904. Kokichi Mikimoto from Japan became the real promoter of cultured pearls.
As I stood on the fare greffe, a woman brought out several trays of black pearls divided into six catergories: A to F. I looked around the tiny room at the few trays that were on top of several cabinets. She explained that it takes four years for a black pearl to be formed and then only one percent of those pearls pass inspection to be certified by the government. They are ranked on orient and luster; color, which ranges from black to gray to peacock green and bronze; shape, the perfect round or pear shape is still most valued; and fourth, purity, best having no scratches, tiny holes, spots, stripes, or unevenness. Then there is the Keshi, which forms when the black pearl nacre rejects the nucleus and forms little odd shaped pearls. These are used in creating novelty jewelry and are becoming quite collectable today.
I was at the best place in the world to find black pearls: most of these pearls will be sent to New York, Paris, and London. Here I found keepsakes for our daughter and granddaughters. I took the small parcel, happily got into the little outrigger canoe, and off we headed across the lagoon to the island. I had not expected to go to a black pearl farm, so this was a special little adventure.
(posted February 2, 2016)