Classically elegant and timelessly beautiful, pearls (a June birthstone) are one of the very few organic materials classified as gems. They are most commonly produced by oysters or mussels, although other types of creatures produce pearls, too (such as abalone or conch). A pearl forms when an irritant enters the mollusk, which will then coat the irritant with layers of nacre (pronounced NAY-ker).
A few pearl facts:
- Pearls are the oldest known gems. Unlike gems formed in the earth, which must be cut and polished to reveal their beauty, pearls can be used just as nature gives them to us.
- Pearls are formed in both freshwater and saltwater. The saltwater varieties include the pearls formed by Akoya, Tahitian, and South Sea oysters.
- Prior to the discovery of oil, the most valuable export from the Persian Gulf was pearls. Once a rare source of natural pearls, the oyster beds there have been destroyed by pollution from the oil industry.
- In ancient times, pearls were so valuable that a Roman general, Vitellius, paid for an entire military campaign by selling just one of his mother’s pearl earrings.
- In 2016, a Filipino fisherman revealed that he had the world’s largest natural pearl. He discovered it when his boat’s anchor snagged on the giant clam which produced the pearl, and kept it for 10 years as a good luck charm. Currently on display at Puerto Princesa on Palawan Island, the pearl is 2.2 feet long and 1 foot wide, and weighs 75 pounds.
Cultured versus Natural Pearls
A natural pearl is one which has had no human intervention. These are quite rare, and therefore quite valuable. The majority of pearls on the market are cultured, meaning that they are grown on pearl farms where the bead nucleus is implanted in the oyster.
The earliest cultured pearls date back to the 13th century, when Chinese pearl farmers would implant tiny carvings of the Buddha into freshwater mussels, which the mollusk would coat with nacre, thus creating Buddha-shaped pearls.
The existence of today’s cultured pearl industry can be credited to three Japanese men: Dr. Tokichi Nishikawa, a marine biologist; Tatsuhei Mise, a carpenter; and Kokichi Mikimoto, a vegetable vendor-turned-pearl-farmer. It was Tatsuhei Mise who received the first Japanese patent for culturing pearls, in 1907. The other two, Dr. Nishikawa and Mikimoto, had been experimenting around the same time, but it was Mikimoto, using the methods developed by the other two, who turned pearl farming into a successful commercial venture.
I recently visited a pearl farm in Halong Bay, Vietnam (photo below) and was able to see a pearl-culturing operation first-hand.
First, a piece of tissue (specifically, the mantle) is taken from a donor oyster and treated with antibiotic – these are the red-stained strips in this photo.
Then, a tiny section of the treated tissue is wrapped around the bead nucleus for the soon-to-be cultured pearl, and is then inserted into the host oyster.
The implanted oysters are placed in net racks and returned to the water. At the pearl farm I visited, they cultivate three types of oysters: Akoya, Tahitian, and South Sea. At this particular farm, they let the Akoya pearls grow for 2 years, the Tahitian pearls for 4 years, and the South Sea pearls for 4 to 6 years.
I love pearls and use them frequently in my designs. Visit studio44jewelry to see more.