Freshwater Pearls Guide: How They Form, Freshwater vs Saltwater, Quality & Care
A freshwater pearl is a real, cultured pearl grown by mussels in lakes and rivers, and it's usually solid nacre all the way through. Freshwater pearls are the pearls most of us actually wear: soft, glowing, a little imperfect, and far more affordable than their saltwater cousins.
At Thread & Touch Jewellery, almost every pearl piece I make uses freshwater pearls, wrapped by hand in my West Auckland studio. This guide covers how freshwater pearls form, how they differ from saltwater pearls, what to look for when you choose one, and how to keep them looking lovely.
What is a freshwater pearl?
A pearl forms when a mollusc coats something inside its shell with layer after layer of nacre, the same iridescent material that lines the inside of the shell. Natural pearls, which form entirely by chance, are now extremely rare. Almost all pearls sold today, freshwater and saltwater, are cultured: a pearl farmer starts the process, and the mollusc does the rest.
Freshwater pearls are cultured in mussels that live in lakes, ponds and rivers rather than the sea. Today most of the world's freshwater pearls come from China. So "cultured freshwater pearl" is not a lesser kind of freshwater pearl. It simply describes how nearly all of them are grown.
How are freshwater pearls formed?
To start a freshwater pearl, a farmer usually places a tiny piece of mantle tissue from another mussel inside the mussel. The mussel then builds nacre around it, slowly, over months to years. Because there is usually no bead at the centre, many freshwater pearls are almost entirely nacre all the way through.
One mussel can grow many pearls at a time, which is a big part of why freshwater pearls are more affordable than most saltwater pearls.
Freshwater vs saltwater pearls: what's the difference?
Saltwater pearls, such as Akoya, Tahitian and South Sea pearls, grow in oysters in the ocean. They are usually started with a round shell bead plus a piece of tissue, and an oyster typically produces only one or two pearls at a time. Here is the short version:
- Where they grow: freshwater pearls in mussels in lakes and rivers; saltwater pearls in oysters in the sea.
- What's inside: freshwater pearls are often solid nacre; saltwater pearls usually have a bead nucleus with a nacre coating.
- Shape: perfectly round freshwater pearls are rarer, while oval, button, drop, rice and baroque shapes are common. Bead-nucleated saltwater pearls are more often round.
- Colour: freshwater pearls naturally come in white, cream, peach, pink and lavender tones.
- Price: freshwater pearls are generally much more affordable, which makes them ideal for everyday jewellery.
Neither is "better". Saltwater pearls are prized for their sharp lustre and round shapes; freshwater pearls for their soft glow, variety of shapes and everyday wearability.
What do the different shapes mean?
Pearl shape is a matter of taste, not quality on its own. These are the shapes you'll see most often in freshwater pearl jewellery:
- Round and near-round: the classic look, and the rarest freshwater shape.
- Drop and oval: lovely on earrings and pendants, because they hang naturally.
- Button: flatter on one side, often used for studs.
- Rice: small, slightly elongated pearls, perfect for delicate, scattered designs.
- Baroque: irregular, organic shapes, every one different.
How do you choose a good freshwater pearl?
Gemmologists look at seven value factors for pearls: size, shape, colour, lustre, surface quality, nacre quality and, for pairs or strands, matching. For everyday jewellery, three of them matter most:
- Lustre: the glow and the reflections on the surface. Good lustre looks bright and soft, not chalky or dull. It's often considered the most important factor for beauty.
- Surface: small marks are normal in a natural material and are part of what makes each pearl unique. Look for a surface that doesn't have deep pits or cracks.
- Size and shape: choose what suits the piece. A small pearl feels delicate on a fine chain; a drop shape moves beautifully on an earring.
Some freshwater pearls on the market are dyed or treated to create stronger colours. If colour matters to you, it's always fine to ask the seller.
How can you tell if a pearl is real?
A simple at-home check is to rub the pearl very gently against the edge of your front tooth. Real pearls usually feel slightly gritty, because of the layered nacre, while glass or plastic imitations tend to feel smooth. Real pearls also feel cool to the touch at first, and you'll usually see small differences in shape and surface between pearls. For a definite answer, a gemmological lab is the only way to be sure.
How do you care for freshwater pearls?
Pearls are soft (around 2.5–4.5 on the Mohs hardness scale) and sensitive to chemicals, so a little care goes a long way:
- Put your pearls on after perfume, lotion and hairspray.
- Take them off before showering or swimming.
- After sweating, rinse with clean water and let them air dry.
- Store them separately in the pouch or box provided, away from sunlight, so harder gemstones and chains can't scratch them.
For more detail, including how to look after gold-plated wire, read How to Care for Pearl, Gemstone & Gold-Plated Jewellery or our Jewellery Care page.
Freshwater pearl pieces to wear every day
Looking for earrings? Browse the full Pearl Earrings collection, or see all necklaces.
In short
Freshwater pearls are real, cultured pearls grown by mussels in lakes and rivers. They're usually solid nacre, come in many shapes, and cost far less than saltwater pearls. Choose them by lustre and surface, and care for them by putting them on after perfume and taking them off before showering or swimming.
Frequently asked questions
Are freshwater pearls real pearls?
Yes. Freshwater pearls are real pearls grown by mussels. Almost all of them are cultured, which means a farmer starts the process and the mussel builds the pearl from nacre.
What's the difference between cultured and freshwater pearls?
"Cultured" describes how a pearl is grown (with human help); "freshwater" describes where it grows. Most freshwater pearls are cultured, and so are most saltwater pearls.
Are freshwater pearls good quality?
They can be. Quality depends on lustre, surface, shape, size and nacre, not on whether the pearl is freshwater or saltwater. A bright, glowing freshwater pearl can be a beautiful piece to wear for years.
Can I wear freshwater pearls every day?
Yes, with a little care. Put them on after perfume and lotion, take them off before showering or swimming, and store them separately.
What metal do you use with your pearls?
Our pearls are wrapped in colour-fast gold-plated or silver-plated copper wire, with plated stainless steel chains and ear hooks. It isn't solid gold or sterling silver, which keeps each piece affordable.
About the author
Yiyi, founder and maker of Thread & Touch Jewellery
I wire-wrap every piece by hand in West Auckland, using natural gemstones and freshwater pearls. You'll find me most Saturdays at Britomart Saturday Market.