In ancient times, there are mainly two types of pearls: Freshwater Pearls & Seawater Pearls, which of both are natural grown. And the structure of both pearls are the same. The reasons for the seawater pearls costing more expensive are the differences of the cluster, size, etc. (For more information, please click here.)
As time changes, we have invented many ways of high-technique to produce pearls. Nowadays, people can created pearls by implanting beads into the oyster, it's hardly to tell the differences from the outside. However, the internal structure of cultured pearls has been changed. Please check the details of the pearls structures as below:
All of natural pearls have the same structure as picture 1. A pearl is composed of calcium carbonate (mainly aragonite or a mixture of aragonite and calcite) in minute crystalline form, which has been deposited in concentric layers. It has an obvious ring structure, and the pearl core of natural pearls is generally sand or small insects.
And most of the cultured pearls have the same structure as picture 2, only a few pearls will have the same structure as picture 1. Cultured pearls will appear to have a perfectly rounded nucleus that's surrounded by a halo of conchiolin and finally a thin outer layer.
Nowadays, the pearls you can see in at market are mainly cultured pearls, natural pearls are very rare because they need a perfect environment within a non-polluted environment. But with the professional technology, the quality of cultured pearls can be as same as the quality of natural pearls, no matter the color, luster, matching, size, etc.
