PEARLS
Natural pearls are very rare. Only in one of every 10,000 oysters, might you be lucky enough to find a single natural pearl. Because of this scarcity, most pearls today are cultured pearls. Pearls are graded and categorized in 5 main categories; color, luster, shape, markings and size.
Color
Body-color is the term used to describe the general color of a pearl. Pearls typically come in cream, yellow, pink, white, silver, or black. Because some pearls have overtones of a secondary color, they may appear in different colors when light reflects off the pearl’s surface.
Luster
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. The larger the pearl, the more calcium carbonate crystals, or nacre, it will have, giving it more luster. When selecting a pearl, consider that the larger the pearl the more luster it will have.
Shape
The rarest pearl shape is round. Shapes that are not spherical or even symmetrical are considered lower quality. Other pearl shapes are oval, off-round, and teardrop.
Markings
As a pearl is created in the oyster, spots and bubbles can develop in the layers of nacre. The pearls with the smoothest surfaces are the most desirable and the most expensive.
Size
Freshwater pearls range in size from about 3.0–7.0mm, Akoya pearls range from about 6.0–8.5mm, and the South Sea and Tahitian pearls can reach sizes as large as 13mm.
