I think everyone knows that pearls are produced by water dwelling animals called shellfish, or mollusks.
Pearls are produced when a foreign object gets inside the shell, and the shellfish is unable to expel the irritant.
When the shellfish fails to expel the object, it forms a sac around it and begins to coat it with a substance (nacre) it normally secretes when growing its shell.
Shellfish have several kinds of tissue hidden inside that shell. Of special note to us is mantle tissue.
Mantle tissue attaches the animal to its shell. It also contains glands that secrete nacre and other shell building material.
Surprisingly, several kinds of shellfish can produce pearls.
Freshwater pearls are sometimes produced by mussels living in streams and lakes.
In saltwater shellfish, the most reliable pearl producer is the oyster. And of course, there are several types of oysters. They come in various sizes and colors, and they produce pearls of various sizes and colors.
Akoya oysters produce the smaller, and often whiter, "Japanese" pearls.
Several species of South Seas oysters produce larger pearls in colors from white to black.
Abalone, conch, and other saltwater shellfish occasionally produce pearls. There are people now experimenting with culturing pearls from these animals.
Around 1900 most known natural saltwater (oyster) pearl beds had been harvested… and few new sources have been discovered since.
Thank goodness for cultured pearls!
If not for the process of culturing pearls, these beautiful, elegant gems would still be the exclusive domain of the very, very rich.
Most people are familiar with the accounts of how Kokichi Mikimoto developed a successful technique for culturing saltwater pearls in the 1890's.
By implanting a shell bead into an akoya oyster, he was able to get the oyster's cooperation in coating the bead with several thin layers of nacre, producing a cultured saltwater pearl.
These techniques have since been exported to other Pacific and Indian Ocean countries and modified to fit local conditions... and the local type of oyster.
Some of these countries produce South Seas cultured pearls, and some produce akoya pearls in competition with the Japanese.
The Japanese pearl growers have dominated the cultured pearl market for the past hundred years or so.
When you see pearl strands, bracelets, rings, and earrings featuring 5 to 8 mm white, rose blush, or cream pearls, you're most likely looking at Japanese saltwater cultured pearls.
Pearl Care and Feeding
Natural pearls are almost all nacre, where cultured pearls are several layers of nacre over a shell bead. Both types of pearls require a bit more care than most other gems.
Nacre can be damaged or discolored by chemicals. You should take precautions to prevent chemicals from coming into contact with pearls… including perfume and cologne.
It's a good idea to always put your pearls on last when getting dressed.
Acids in skin oil can damage pearls. To the extent practical avoid prolonged contact with perspiration.
Use a soft, damp cloth to gently clean pearls.
Have pearls restrung when the string becomes soiled and discolored.
Pearls are beautiful and elegant. Enjoy wearing them.
We have some nice saltwater cultured pearl studs for sale on our Pearl Page.
Don't forget, we're offering free shipping on all orders over $99.
Just deduct the shipping charge when you fill out the order form. If you forget, we'll deduct it for you.
Until next month… please, visit me anytime at AZGem.com for a great selection of colored gems at great prices.