What is mother of Pearl?

Mother of Pearl, also known as Nacre, is an organic material produced inside oysters. It is not known exactly what elements causes its formation.
Oysters secrete it as a defense mechanism against foreign agents, such as grains of sand.

It should be remembered that nacre is not the same as pearl. The pearl is an organic gem composed of layers of nacre, which usually adopts a round shape.

The uses of mother-of-pearl are varied, both for decorative elements and for jewelry or watches. Traditionally, mother-of-pearl spoons have been made to eat caviar.