Information on Seawater Pearls:
Oysters produce seawater pearls in the harbor. The shape of this type of pearls is usually round and they grow a lot more slowly than the freshwater pearls. That is why they are more expensive but it doesn’t mean all seawater pearls are better quality than freshwater pearls. In both types of pearls there are different qualities depending on the luster and imperfections.
No matter which type, a pearl is more precious when the surface has better luster and less imperfections. And usually size plays a very important role on how much a pearl or strand of pearls worth, because the bigger a pearl is, the more expensive it is since it needs longer time to grow.