Pearls are formed inside the shells of oysters, but natural pearls are rare. Most pearls today are cultured pearls meaning they are grown in labs. A tiny bead is implanted in an oyster, so that it is gradually coated in layers of a beautiful, iridescent substance called nacre which build up to create a lustrous pearl.

The general color of a pearl is also called the body color. Typical pearl colors are white, cream, yellow, pink, silver, or black. A pearl can also have a hint of secondary color, or overtone, which is seen when light reflects off the pearl surface. For example, a pearl strand may appear white, but when examined more closely, a pink overtone may become apparent.

Pearls produce an intense, deep shine called luster. This effect is created when light reflects off the many layers of tiny calcium carbonate crystals that compose the pearl. This substance is called nacre. When selecting a pearl, consider that the larger the pearl, the more nacre it has, so it will also exhibit even more luster. Compare a 5mm Freshwater cultured pearl with a 10mm South Sea cultured pearl and the difference in the amount of nacre is obvious. The difference in luster is as clearly visible as the difference in the pearl sizes.

As an oyster creates a pearl, the layers of nacre do not always adhere smoothly. Sometimes spots and bubbles can appear in the layering process. Pearls with the smoothest surfaces are the highest-quality, most sought-after pearls.

The size of the pearl greatly depends on the type of pearl. Freshwater pearls range in size from about 3.0–7.0mm, Akoya pearls range from about 6.0–8.5mm, and South Sea and Tahitian pearls can reach sizes as large as 13mm.

Magic & Myth

Historically symbolic of purity, innocence and faith, pearls enhance personal integrity and help clear the mind so that it can be a clean channel for wisdom and spiritual guidance. These Moon and water ruled "gems" enhance sincerity, truth and loyalty and bring calming reflection and inner peace.

Pearls have long been used medicinally. They were thought to cure everything from fevers to stomach ulcers.