Mother of pearl refers to the coating on the inside of mollusk shells. These shells include freshwater pearl mussel shells, pearl oyster shells, and abalone shells. The coating, also called nacre, is naturally produced by the mollusk for protection from parasites and it appears as an iridescent, multicolored sheen. In other instances, such as when a piece of sand enters the shell, the nacre coats the sand and becomes a pearl. Mother of pearl is strong and resilient due to the brittle platelets and thin layers of biopolymers.
This stone is popularly used for bath, flooring, and wall tiles, as well as on decorative counters and fireplaces. As a natural material, the color depends on the type and color of the shell, with white being the most common hue. It is also available in shades of yellow, pink, green, black, and brown, and can be dyed.