Moijey Fine Jewelry & Diamonds Blog

Pearls: An Organic Joy

Originally posted on June 1st, 2017

Updated April 17th, 2020

Happy June, ladies, and gentlemen! The sun is shining, the birds are singing, and pearls are ready to be worn for any occasion. A June birthstone, the pearl is ethereal and romantic! Our own Daniel Moijueh wrote a  lovely article about the fundamentals of pearls. To celebrate the beginning of June, we will continue to explore the wonders and mysteries of pearls.

Three years ago, I had the joy of attending a lecture on pearls by Teresa Tkacik, M.S.N., F.N.P.C., a pearl expert. As a gemologist, I loved every minute of it! Tkacik's speech was rich in detail about how pearls came to exist in the world.

Pearls, according to Tkacik, are formed by two types of mollusks: bivalve and univalve. Most pearl-bearing oysters are bivalves, meaning that they have two-part shells instead of being a single shelled univalve mollusk.

The pearl formation starts when a foreign object, like a parasite, enters the mollusk and irritates the mollusk's mantle, the organ that lines the shell of the mollusk. The mollusk tries to protect itself by coating the irritant with nacre. Nacre is a natural substance made from aragonite and conchiolin. Aragonite is crystallized calcium carbonate platelets, and conchiolin is the organic binding agent that holds the platelets together. The platelets are hexagonal and are layered and bound together to produce the phenomenon we all adore called iridescence. Here are examples of remarkable pearls with beloved iridescence from the Smithsonian.

Most pearls in the market today are cultured, meaning that human intervention was involved in producing beautiful pearls. Instead of parasites, pearl farmers use beads carved from mother of pearl shell. After the farmers insert the bead into the mollusk, the farmers work to ensure that the mollusks are healthy and their environment is clean.

In the gem and jewelry industry, there are four main types of pearls: the Akoya, the South Sea, the Tahitian, and Freshwater.

Akoya pearls are the most familiar variety in the industry. They are produced in Japan, Vietnam, and China by the Pinctada fucata oyster. The common name for oyster is Akoya in the Japanese language, therefore the name Akoya.

South Sea pearls, more satiny than shiny and equally beautiful, are produced by two varieties of the Pinctada maxima oyster: the gold-lipped and the silver-lipped. The two oyster types account for different colors. South Sea pearls originate in Australia, Indonesia, and the Philippines.

Tahitian pearls mainly come from the islands of French Polynesia and the Cook Islands. The Pinctada margaritifera or black-lipped oysters are responsible for producing stunning pearls that range from black to white. In the industry, there are names like a peacock (dark green-gray to blue-gray with pink to purple overtones), aubergine (dark grayish purple), and pistachio (yellowish-green to greenish-yellow). These names describe the unusual colors black-lipped oysters produce.

For freshwater pearls, the name speaks for itself. They come in all kinds of colors, shapes, and sizes. Freshwater lakes, rivers, and ponds are the sources of these pearls, and many of them in China, which produces the majority of the world's freshwater cultured pearls, and the United States. Instead of an oyster like the saltwater pearls, freshwater pearls grow in a mussel called the Hypriopsis cumingi.

There is so much more the world of pearls. Stop by Moijey next week, and we can talk about the history of how pearls came to be cultured in the first place.

A special thank you to Teresa Tkacik for her lecture and insight on pearls. It was an event I thoroughly enjoyed and will not forget anytime soon.