Pearl Guide

Both natural and cultured pearls are grown by oysters and are therefore considered valued jewels-gifts of nature. The only difference between them is that natural pearls begin by accident while cultured pearls are initiated by man. A skilled jeweler can usually look down the drill hole of a pearl and determine the origin. However, the only sure way to tell the difference between a natural and cultured pearl is by using an X-ray machine.

Imitation pearls, on the other hand, are man made by mechanical processes and have no real jewel value.

Better imitation pearls are made from beads of glass, ceramic, shell, or plastic which are coated with a varnish generally made of lacquer and ground fish scales to simulate the iridescence and color of a pearl.

Imitation pearls go by many names. Some, unfortunately, are used to mislead consumers. The words "fashion, faux, simulated, organic, man-made, 'Mallorca'," or simular regional names are all terms that are currently applied to manufactured, imitation pearls.

Most pearl experts can tell the difference between imitation and real pearls by sight alone. However, due to sophisticated manufacturing and polishing techniques, it may be difficult for the average consumer to distinguish a natural or cultured pearl from a good imitation by sight. An easy way to tell the difference is the "tooth" test. A strand of imitation pearls slowly rubbed across the front teeth will feel smooth. A strand of natural or cultured pearls will feel a little gritty. This "grittiness" that is felt is from the crystalline structure of nacre that forms real and cultured pearls.



Lustre is a combination of surface brilliance and a deep-seated glow. The lustre of a good quality pearl should be bright and not dull. You should be able to see your own reflection clearly on the surface of a pearl. Any pearl that appears too white, dull or chalky indicates low quality.


Cleanliness refers to the absence of disfiguring spots, bumps or cracks on the surface of a pearl. The cleaner the surface of the pearl, the more valuable.



Since cultured pearls are grown by oysters in nature, it is very rare to find a perfectly round pearl. However, the rounder the pearl, the more valuable it is. Baroque pearls, which are asymmetrical in shape, can be lustrous and appealing, and often cost less than round pearls.



Cultured pearls come in a variety of colors from rosé to black. While the color of a pearl is really a matter of the wearer's preference, usually rosé or silver/white pearls tend to look best on fair skins while cream and gold toned pearls are flattering to darker complexions.




Cultured pearls are measured by their diameter in millimeters. They can be smaller than one millimeter in the case of tiny seed pearls, or as large as twenty millimeters for a big South Sea pearl. The larger the pearl, other factors being equal, the more valuable it will be. The average sized pearl sold today is between 7 and 7-1/2 millimeters.



Freshwater pearls are grown in bays, lakes and rivers, primarily in Japan, China and the United States. When freshwater pearls are cultivated, one mussel can be harvested many times, yielding numerous pearls simultaneously. They are often smaller and less symmetrical than Akoya pearls, and may not be as well matched on a strand, but otherwise look much like Akoyas. And the quality of freshwater cultured pearls has improved dramatically in the past decade. Freshwater pearls represent the most exceptional value to the consumer, with a cost of about 1/3 the price of Akoyas.


Akoya pearls are the classic cultured pearls of Japan. They are the most lustrous of all pearls found anywhere in the world. In recent years, China has been successful in producing Akoya pearls within their own waters. However, at this time they are unable to produce as brilliant a lustre as high quality Japanese Akoya cultured pearls.


White South Sea cultured pearls are grown in large tropical or semi-tropical oysters in Australia, Myanmar, Indonesia and other Pacific countries. They generally range in size from 10mm to 20mm and command premium prices because of their relative rarity and large size.


Tahitian cultured pearls are grown in a variety of large pearl oysters found primarily in French Polynesia. Their beautiful, unique colors (which can range from light gray to black, and green to purple) and large size can command very high prices.


Mabe pearls are hemispherical cultured pearls grown against the inside shell of an oyster rather than within the oyster's body. They generally are used in earrings or rings, which conceal their flat backs.

Pearl information provided in cooperation with the Cultured Pearl Information Center.


Cultured pearls are precious jewels and should be treated as such. They're also the products of living creatures. Cultured pearls are formed when an irritant is introduced into a mollusk. The mollusk secretes a substance called nacre, which covers the irritant and produces the pearl. Nacre gives pearls the rainbow of colors and lustre that makes these gemstones so treasured, but its delicate nature also makes pearls particularly susceptible to damage. For this reason you should be extra careful with your cultured pearl jewelry.

Apply cosmetics, hair sprays and perfume before putting on any pearl jewelry. When you remove the jewelry, wipe it carefully with a soft cloth to remove any traces of these substances.

You can also wash your pearl jewelry with mild soap and water. Do not clean cultured pearls with any chemicals, abrasives or solvents. These substances can damage your pearls.

Do not toss your cultured pearl jewelry carelessly into a purse, bag or jewel box. A pearl's surface is soft and can be scratched by hard metal edges or by the harder gemstones of other jewelry pieces.

Place cultured pearl jewelry in a chamois bag or wrap them in tissue when putting them away.

Cosmetics, perspiration, oils and ordinary wear weaken and stretch the threads on which the pearls are strung. Have your pearls restrung once a year to prevent breakage. Make certain the pearls are strung with a knot between each pearl. This will prevent loss of pearls if the string should break.

Pearl care information provided in cooperation with Jewelers of America.