Most jewelry elements, like gemstones and metals, have to be mined, cut and shaped into something pretty, but the pearl is naturally beautiful, forming its glow and radiance in the oyster. We all know that pearls come from an oyster, but do you know why or how?
The creation of a pearl all starts when an object whirling in the ocean lands in the shell of an oyster, and cannot come out. The oyster, now irritated by the invader, defends itself by releasing a firm yet smooth crystalline substance, nacre, covering the object inside the shell. The oyster will continue to produce nacre to cover the invader, and in the process forms a pearl.
Pearls come in a variety of colors, but how do the oysters produce the different colors? There are many varying factors that contribute to the color change: the type of oyster, the thickness or the number of layers of nacre, but it is usually just chance.
Pearls, like diamonds, come in numerous grades reflecting the range of quality that comes from a natural process. The majority of pearls do not meet even the minimum standard for use in jewelry. Jewelry-grade pearls begin with ‘A’ grade, which means a clear finish, high luster with only slight surface blemishes. A pearl’s luster is a result of the depth of the nacre, and since the nacre builds up over time, the longer a pearl remains in the oyster, the deeper the luster becomes. The grading system moves up through ‘AA’ and ‘AAA’ which is the highest grade, although some companies use additional intermediate grades. In all cases, higher grades reflect a more clear and reflective surface with minimal surface blemishes. And, of course, the occurrence of pearls at each higher grade is successively more rare, and thus more expensive.