In ancient times, freshwater pearls come from natural oyster shells. A pearl starts to form when an irritant enters a pearl oyster. To reduce the irritation, the pearl secretes a special type of liquid that wraps around the irritant. A new layer is constantly built upon the previous layer, until the pearl becomes of considerable size. It is very difficult to locate a natural pearl. Hundreds of pearls have to be opened with a special tool before someone can tell whether there is a pearl in it or not. This is a very time consuming process, and there is no guarantee of success. Therefore, such pearls are very valuable. In the past, only nobles and highly affluent families can afford to own pearls.

However, in modern times, pearls are produced in a very different manner. Pearls that are produced with human intervention is known as cultured pearls. Freshwater pearls are usually cultured pearls. In other words, they have gone through a special operation to ensure that pearls are produced by these oysters. The pearls are then harvested by the pearl farmers, and sold to trading companies, which in turn sell the pearls to jewelry retailers or consumers.