The differences between Seawater and Freshwater Pearls
Freshwater pearls are grown in freshwater lakes and rivers in a large (21 cm in diameter) freshwater mussel. With freshwater pearls there is no nucleus implanted, but a piece of the mantel of the mussel is placed inside the mussel to create an irritation and through that pearls are produced.
The freshwater mussel can produce up to 60 pearls at once and so the number of pearls harvested per mussel is much higher than seawater pearls. Therefore freshwater pearl prices are lower than seawater pearl prices.
Shapes of freshwater pearls are also more oval when compared to the rounder shape of seawater pearls as no nucleus is implanted in the freshwater mussel.
Shapes of freshwater pearls are more varied than seawater pearls. The lustre of freshwater pearls is also good but lacks the depth and richness of seawater pearls.
Seawater pearls are grown in the ocean in oysters. A nucleus (bead) made from mother of pearl shell is implanted into the oyster and placed back in the ocean at pearl farms to cultivate the pearl.
Oysters used for cultivating seawater pearls normally produce only one pearl. Seawater pearl shapes can range from perfect round, off-round, semi-round, semi-baroque and baroque. The lustre of seawater pearls is very deep and rich.