Question

collect information about how a natural pearl is formed

Answer 1

The formation of a natural pearl begins when a foreign substance slips into the oyster between the mantle and the shell, which irritates the mantle. ... The mantle covers the irritant with layers of the same nacre substance that is used to create the shell.

Answer 2

HI

Natural Pearls form when an irritant - usually a parasite and not the proverbial grain of sand - works its way into an oyster, mussel, or clam. As a defense mechanism, a fluid is used to coat the irritant. Layer upon layer of this coating, called 'nacre', is deposited until a lustrous pearl is formed.

Hope it proved to be beneficial....