List of pearls by size

A pearl is a hard, glistening object produced within the soft tissue (specifically the mantle) of a living shelled mollusk or another animal, such as a conulariid.

The finest quality of natural pearls have been highly valued as gemstones and objects of beauty for many centuries.

The most valuable pearls occur spontaneously in the wild, but are extremely rare.

Whether wild or cultured, gem-quality pearls are almost always nacreous and iridescent, like the interior of the shell that produces them.

However, almost all species of shelled mollusks are capable of producing pearls (technically "calcareous concretions") of lesser shine or less spherical shape.