With cultured pearls, a particle is inserted into the oyster or mussel by human being. With natural pearls, a particle gets inside the oyster or mussel by accident. Saltwater pearls are from the oyster family in the large tropical or semi-tropical oysters in ocean. Most of them are round. Freshwater pearls are from the mussel family and can be found in fresh water like rivers, lakes and ponds.
Freshwater pearls are usually smaller, from potato shape to semi-round shape.
They are less expensive than saltwater pearls. Freshwater pearls are highly affordable pearls in jewelry designing. Larger pearls are more valuable than smaller pearls. Round pearls are more valuable than less round. The higher the glossier is, the higher the price is.