Monday, June 29, 2009

Pearls before Swine

Pearls, beautiful, lustrous, glowing pearls. And to think it all started with a grain of sand.

The mollusk, that' s oyster to you and me, opens its shell to pass fresh water over itself and snag tiny bits of food. Sometimes what it snags is a grain of sand or piece of shell. If the mollusk can't get rid of the bit of grit it begins to coat it with a substance it produces called nacre. Coating the grain of sand makes it less irritating. As time passes the grain is coated with many layers of nacre. Eventually you end up with a lustrous pearl.

Not all pearls are gem quality. The pearl can be lopsided, have an irregular surface, or the coloring of the pearl is grayish instead of glistening. If the irregularity is only on one side and the pearl looks good otherwise it can be set in jewelery with the flaw at the back of the piece where it won't be noticed.

Pearls can be from fresh water or salt water mollusks. Salt water is more expensive.

Colors range from white, yellow, pink, to gray. South Sea Pearls, sometimes called Tahitian pearls, are some of the most expensive pearls. They are larger, because the mollusk is larger, and the colors are iridescent black, purple, and dark gray. The pearl looks like a rainbow is playing against the dark surface.

Natural pearls are very expensive and difficult to find in jewelry since the Japanese began culturing pearls. Cultured pearls are simply oysters in an oyster bed that has been seeded with a nucleus.

Good cultered pearls have been left in the oyster over several years to build up layers of the pearl. Cheap cultured pearls start with a much bigger seed core and then left in the oyster only long enough to gather a few layers. Those layers can wear off.

The value of a pearl is based on 5 factors: cleanliness, shape, luster and orient, and color.

No comments: