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 ...

clams and mussels can also create pearls, though this is much less common. Most pearls come from oysters, which thrive in both freshwater and saltwater environments. Oysters are bivalves that ...

Moreover, pearls are formed by living creatures, including abalone, clams, mussels and ... are typically more charcoal than ...