How Do Oysters Make Pearls? - Natural History Museum

Home » How Does Clams Make Pearls » How Do Oysters Make Pearls? - Natural History Museum

Maybe your like

How do oysters make pearls?

Pearls are made by marine oysters and freshwater mussels as a natural defence against an irritant such as a parasite entering their shell or damage to their fragile body.

The oyster or mussel slowly secretes layers of aragonite and conchiolin, materials that also make up its shell. This creates a material called nacre, also known as mother-of-pearl, which encases the irritant and protects the mollusc from it.

When pearls are cultured commercially an irritant is manually inserted into a mollusc to promote the production of mother-of-pearl.

Nacre can form naturally around almost any irritant that gets inside the shell, creating some very unique and precious pearls.

Other bivalve molluscs and gastropods can produce pearls, but these aren't made of nacre.

Cultured pearls within an oyster shell, its surface shiny with nacre © Ron Ramtang/ Shutterstock

Next question: What do killer whales eat?

Dive in

Explore pioneering marine science and life beneath the waves.

Accept cookies?

We use cookies to give you the best online experience. We use them to improve our website and content, and to tailor our digital advertising on third-party platforms. You can change your preferences at any time.

Manage my preferencesYes, accept all

Tag » How Does Clams Make Pearls