Freshwater Pearls

Cultured freshwater pearls have caused a revolution in the pearl industry making pearls affordable and attainable. In addition, the multitude of shapes, colors and sizes have pushed pearl jewelry design into exciting new directions. The quality of today’s freshwater pearls, whilst continually improving, has already reached the level of many saltwater pearls, making them a true alternative for pearl connoisseurs.

Pearl Type Freshwater
Oyster Hyriopsis cumingi
Cultivation Mantle tissue
Size 1 to 11 mm
Shape Round, Semi-Round, Oval, Drop, Baroque, Button
Natural Color White, Lavender, Mauve, Pink
Treated Colors Black
Region China, Japan
Rarity Common


Cultured freshwater pearls are produced by surgically inserting tiny pieces of mantle tissue into the Hyripsis cumingi mussel in a process called nucleation. Anywhere from 24 to 32 pieces of mantle tissue can be nucleated into a single mussel. After nucleation, the mantle tissue, which acts as an irritant, is enclosed in a sac by the mussel and secreted by layer upon layer of nacre. Nacre is the calcium-carbonate compound that covers pearls and gives them that unique iridescence. The cultivation process for freshwater pearls can be anywhere from 2 to 6 years, at the end of which 24 to 32 beautiful pearls can be harvested from one mussel.

The unique aspect about freshwater pearl cultivation is that no bead is nucleated along with the mantle tissue, like is common for saltwater pearls. This results in pearls that are majority nacre making them more durable and less prone to chipping or wear. On the flip side, the lack of a bead makes it less likely for freshwater pearls to be round in shape.

In the last couple of years, Chinese farmers have started experimenting with bead nucleated freshwater pearls. As hoped for, this has resulted in larger and rounder freshwater pearls, but the quality is still quite poor. While still a work in progress, many in the industry believe it is only a matter of time before large freshwater pearls can rival saltwater pearls.

The overwhelming majority of freshwater pearl production today comes from China, but cultivation on a much smaller scale also occurs in Japan and the United States. The United States is of particular importance to the pearl industry as the vast majority of the round beads or nuclei used in pearl cultivation come from mussels in the Mississippi River, located in the Southern United States.

Freshwater pearls have their own unique luster characteristics, partly because of their all nacre structure. The luster of high quality Freshwater pearls is deep and sharper then that of South Sea pearls, but not quite matching the metallic type luster of Akoya pearls.

What colors, shapes and sizes do they come in? 
The true allure of freshwater pearls is in the broad variety of colors, shapes and sizes that are available. White is the predominant color, but they are a multitude of other naturally forming colors including pink, lavender and mauve colors.

Freshwater pearls also come in a range of black colors through a treatment that involves dyeing or irradiating the pearls. The treatment is permanent and enhances the pearls by offering a unique color with the same deep luster as natural white freshwater pearls. While some black freshwater pearls can match the color of black Tahitian pearls, they are subtle differences. The most common black freshwater colors are variations of green-peacock, deep sapphire blue and dark onyx black.

Rarity and Value 
Classifying freshwater pearls as rare, when annual production is estimated to be close to 1500 tons might seem strange. The reality is that the majority of the1500 tons is below gem grade and crushed to form a medicinal powder that is primarily used in the cosmetics industry.

The cream of the crop of freshwater pearl production, pearls that have high luster, well-defined shapes and clean surfaces is relatively scarce. The volume of production and relative cheapness, still means there is a lot of inferior quality freshwater pearls out there. It is a lot more common to see sub-standard Freshwater pearls in a store, then Japanese Akoya or South Sea. This is partly due to China not setting any quality control or export restrictions to maintain quality like some other pearl producing countries do.

Even so, the good news for consumers is that top quality freshwater pearls can be had for a fraction of the price of similar South Sea or Akoya pearls. The challenge is to find the retailer or brand that has the expertise, willingness and resources to offer high quality freshwater pearls.

Click here to view the Mikura Freshwater Collection 
Have further questions on Freshwater pearls? Write to us.