Pearls are produced in both salt and fresh water, but the difference is astounding. Usually, the salt water variety of pearls are of a better quality and are also more expensive than pearls found in salt water; however, the choice between fresh water and salt water pearls is completely personal.

For starters, pearls are made from shellfish. When an irritant, such as a piece of sand, invades the delicate lining of the creature, it secretes a smooth substance to coat the irritant, thus creating a pearl. Salt water and fresh water pearls are both made in the same fashion. This substance, known as nacre or mother of pearl, slowly builds up the irritant until a pearl is formed.

The main difference between salt water pearls and fresh water pearls is the type of create that produces this natural gemstone. Salt water pearls are produced by oysters that inhabit the seas and oceans. In days past, the only way to harvest salt water pearls was to dive to tremendous depths to recover the oysters. Today, these oysters are grown in farms, but the pearls produced are of supremely high quality.

Fresh water pearls are produced by mussels that burrow in the sandy bottoms of rivers, lakes, and streams. Like salt water pearls, the mussels that produce fresh water pearls are also farmed. In most places, "hunting" mussels to harvest their pearls is illegal due to the havoc it can cause on the ecosystem.

One can immediately tell the difference between a fresh water and salt water pearl by its appearance. Whereas salt water pearls are—or should be—completely round, fresh water pearls have a lumpy, potato-like shape. Usually, fresh water pearls are described as off-round, egg, or Baroque, and come with a more affordable price tag due to this irregular shape.

The colors of fresh water pearls encompass the entire rainbow. While salt water pearls come in a wide array of colors, fresh water pearls usually take on the hue of the mussel's shell. Fresh water pearls can range from the traditional white, cream, and pink to more unusual shades like lavender, and copper. Although these latter colors tend to raise the price on fresh water pearls, the color of choice is purely at the whim of the buyer.

Many potential pearl buyers have the common misconception that the fresh water pearl is not "real." This is completely untrue, as both the fresh water and the salt water pearl are equally authentic. The choice between the two depends on the tastes and the budget of the wearer. Some individuals enjoy the irregular Baroque shapes and special colors of the fresh water, where others want the classic white round offerings of the salt water pearl.