The Story of Cultured Pearls

Only a hundred years ago, pearls were worn almost exclusively by royalty. Pearls were found only by divers in exotic locations, and they were a rare find. They were the single most expensive gemstone because it was so rare to find a round pearl with good nacre. Such a find was a one in a million victory for pearl divers. Now you can find a delightful array of pearl jewellery across the price spectrum. What happened? Pearl culturing. Pearls are still loved by royalty, and they are still just as beautiful, but the advent of pearl culturing has changed the market – very much for the better.

Kokichi Mikimoto, the son of a Japanese noodle maker, and his wife Ume had a dream. Together they set about to do what sounded at the time like a fairy tale - entice oysters to produce round pearls on demand. The Mikimotos did not know that the secret of getting oysters to produce pearls had already been discovered by two others. Government biologist Tokichi Nishikawa and carpenter Tatsuhei Mise had each independently learned that inserting a piece of oyster epithelial membrane (the lip of mantle tissue) with a nucleus of shell or metal into an oyster's body or mantle causes the tissue to form a pearl sack. That sack then secretes nacre to coat the nucleus, thus creating a pearl.

In years of trial and error, Mikimoto did contribute one crucial discovery. Whereas Nishikawa nucleated with silver and gold beads, Mikimoto experimented with everything from glass to lead to clay to wood. He found he had the highest success rates with round nuclei cut from U.S. mussel shells. Although some countries continue to test other nuclei, U.S. mussel shells have been the basis for virtually all cultured saltwater pearls for 90 years. Today’s freshwater pearl culturing technique is rooted in Mikimoto’s discovery.

Mikimoto had received an 1896 patent for producing hemispherical pearls, or mabes, and a 1908 patent for culturing in mantle tissue. Although he was not the only one to patent a method to culture pearls, Mikimoto revolutionized pearling. He was a flamboyant showman and determined promoter. His workers created massive pearl structures, which he displayed at every major international exposition. Thanks to Mikimoto, pearls are no longer exclusively for royalty.

Mise received a patent for his grafting needle in 1907. When Nishikawa applied for a patent for nucleating, he realized that he and Mise had discovered the same thing. In a compromise, the pair signed an agreement uniting their common discovery as the Mise-Nishikawa method, which remains the heart of pearl culturing.

Mikimoto could not use the Mise-Nishikawa method without invalidating his own patents, so he altered the patent application to cover a technique to make round pearls in mantle tissue, which was granted in 1916. Mikimoto then began an unprecedented expansion, buying rights to the Mise-Niskikawa method and eclipsing those originators of cultured pearls, leaving their names only for history books.

Pearls will always be a classic luxury and a mark of style and distinction, perfect for a bride to wear at her wedding and for any woman to wear at the opera, a charity ball, or any other event where she wishes to look her best. Pearls offer true elegance and beauty, not bling.