Test Your Pearl

Pearls are an organic gem, created when an oyster covers a foreign object with beautiful layers of nacre. Long ago, pearls were important financial assets, comparable in price to real estate, as thousands of oysters had to be searched for only one pearl. They were rare because they were created only by chance.


Today pearls are cultured by man: shell beads are placed inside an oyster and the oyster is returned to the water. When the pearls are later harvested, the oyster has covered the bead with layers of nacre. Most cultured pearls are produced in Japan. In the warmer waters of the South Pacific, larger oysters produce South Sea cultured pearls and Tahitian black cultured pearls, which are larger in size. Freshwater pearls are cultured in freshwater mussels, mostly in China.

The quality of pearls is judged by the orient, which is the soft iridescence caused by the refraction of light by the layers of nacre, and luster, the reflectivity and shine of the surface. Fine pearls do not have any flaws or spots in the nacre: it has an even smooth texture. Other factors which affect value are the regularity of the shape, size, and color: rose tints are the most favored.

Cultured pearls and natural pearls can be distinguished from imitation pearls by a very simple test:
Flaw Test
Examine the pearls for flaws. If they appear flawless, this is a sign they are imitations. Also note the types of flaws present. Many of those found on cultured pearls look different from those on imitations.

Overtone Test
Look for overtone colors in the pearls. Imitations frequently have none, and when they do the overtones all tend to look the same. It’s normal for cultured and natural pearls to have overtones, and these overtones often vary in color within the strand.

Tooth Test
Rub the pearls lightly along the biting edge of your upper front teeth. If they feel gritty or sandy, it’s likely they are cultured or natural pearls. If they feel smooth, they are probably imitations.

Bounce Test
Bounce the pearls in your hand. If they feel unusually light, they’re most likely made of plastic or filled with wax. Solid glass beads may feel heavier or about the same as cultured and natural pearls.