Why Are Freshwater Pearls Not Round?

If you have spent any time browsing pearls to use in your jewelry creations, you’ve undoubtedly noticed that freshwater pearls offer much more variety than their saltwater counterparts. They form in a diverse range of colors, sizes and shapes, and, because of this, they are used to create one-of-a-kind pieces that are both beautiful and unique. 

Freshwater pearl
One of the features of freshwater pearls that draws a great deal of curiosity is their shape. While the most valued saltwater pearls are those that are perfectly spherical in shape, perfectly round freshwater pearls are extremely rare. Instead, they tend to occur in a wide range of other shapes. Exactly why are freshwater pearls not round, though? In this blog post, we will answer that question and provide you with additional information about these unique stones.
 

Where Do Freshwater Pearls Come From?

Freshwater pearls are commercially formed inside bivalve mussels in China, Japan and the United States. Chinese pearl farms, however, are the leading source of freshwater pearls. At these farms, 24 to 32 pieces of mantle tissue are surgically implanted in each mussel. A sac forms around each piece of tissue, and cells start to produce a substance known as nacre. This process forms a calcium-carbonate compound–better known as a pearl. 

The mussel continues depositing layer after layer of nacre around the tissue over the course of two to seven years. When the pearls are ready to be harvested, each mussel contains over two dozen brilliant gems. 

Why Freshwater Pearls Are Not Round

Oyster Shell and Pearl
The reason why freshwater pearls are not round can be explained by the implantation process. Natural saltwater pearls form when a grain of sand–which is mostly round–enters a pearl-producing mollusk. In cultured saltwater pearls, a round bead is implanted to create a round pearl. 

During the implantation process for freshwater pearls, however, a piece of mantle that has been cut from the inner lining of a donor mussel is used. This results in pearls that are composed entirely of nacre rather than containing a piece of sand or a bead nucleus. The nacre forms in a more random manner instead of building up around a round object, which results in pearls in various shapes. 

Common Freshwater Pearl Shapes

While saltwater pearls are most desirable when they are perfectly round, freshwater pearls are prized for their unique shapes (as well as their colors). While it is possible for a perfectly spherical freshwater pearl to form, such happenings are incredibly rare. Instead, they usually form in oval, potato, coin, button, rice or stick shapes. Baroque freshwater pearls with asymmetrical shapes and uneven surfaces are also common. 

Keshi pearls are another unique option. They form in Akoya oysters and span the gap between natural and cultured pearls. Keshi pearls are found inside cultured pearls, but they occur without a nucleus. Instead, they are formed entirely from nacre. Most often flat in shape, they display a spectacular sheen and can occur in a wide range of colors. 

Freshwater Pearl Colors

Freshwater Pearl Color Beads
The other intriguing feature of freshwater pearls is their ability to form in multiple colors. While most saltwater pearls are white or off-white, pearl farms are capable of producing pink, yellow, blue, green, orange and even black freshwater pearls. Some are also color-enhanced to be especially vibrant. Because freshwater pearls are available in such a wide range of colors, they are popular among creative jewelry designers who prefer creating one-of-a-kind pieces as opposed to accessories that are more traditional in appearance. 

The vast assortment of colors also makes it easy to pair freshwater pearls with other gemstones and virtually any type of metal. Many people choose to use these unique gems in their creations simply because they offer so much more versatility than saltwater varieties.

Conclusion

Freshwater pearls are unique gems that are popular among jewelry makers and wearers around the world. They made pearls more affordable for the general public, and they are valued for their individuality rather than a uniform appearance. While pearls that are perfectly round–or close to it–remain the most valuable and desirable in certain circles, there are plenty of other people who prefer the interesting shapes and rainbow of colors that can only be found in cultured freshwater pearls. 

If you are interested in adding freshwater pearls to your collection of jewelry-making supplies, we have you covered. Browse our vast selection today to find the pieces that are perfect for your next project!