Oysters have been a source of fascination for centuries, particularly due to their ability to form pearls. But why do oysters have pearls? In this article, we will explore the mystery of pearl formation and discuss why oysters have pearls.

What Are Pearls?

Pearls are round, lustrous objects that are formed when a mollusk produces calcium carbonate crystalline form around an irritant inside its shell. There are two major types of pearls on the market today: Freshwater Pearls and Saltwater Pearls, They can range in color from white to black, but the most sought-after are the white and cream-colored pearls.


The most valuable pearls are natural pearls, which are formed by a mollusk as a result of an irritant or a foreign object. Natural pearls are incredibly rare, but they can be worth a lot of money. Cultured pearls, on the other hand, are formed when a mollusk is given a deliberate irritant, such as a tiny bead or a piece of tissue, and allowed to form a pearl around it.

How Do Oysters Form Pearls?

When an irritant, such as a grain of sand, gets inside an oyster's shell, the oyster reacts by coating it in layers of nacre. Nacre is a substance secreted by the oyster that contains calcium carbonate. This process can take anywhere from six months or up to several years.