What is a Cultured Pearl?
Natural pearls are so rare to find in nature that almost all pearls sold today are cultured. To create a cultured pearl, a tiny bead is implanted into the oyster and gradually over time the oyster coats the bead in many layers of natural minerals and proteins. These layers are referred to as nacre (Nay-Ker.) It is the nacre that gives pearls their beautiful luster and colour.
Choosing the Right Pearl
There are several different Pearl types to choose from – Akoya, Freshwater, South Sea, and Tahitian cultured pearls are the most familiar. Each type comes in different shapes, sizes and qualities. And all these factors determine the rarity and value of the Pearls.
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 (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.
The general colour of a pearl is also called the body colour. Typical pearl colours are white, cream, yellow, pink, silver, or black. A pearl can also have a hint of secondary colour, 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.
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.
As a mollusk 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 rarest pearl shape is round. Shapes that are not spherical or even symmetrical are considered lower quality than round pearls. Akoya, Tahitian, and South Sea pearls found in jewellery are usually more round, while Freshwater pearls can be oval or slightly off-round.