Nacre, also known as mother of pearl, is an organic-inorganic composite material produced by some mollusks as an inner shell layer; it is also what makes up the outer coating of pearls. It is strong, resilient, and iridescent. The outer layer of pearls and the inside layer of pearl oyster and freshwater pearl mussel shells are made of nacre.
Mother of Pearl is made from several different varieties of shells.
The designation mother-of-pearl apparently came into English early in the 16th century via a translation of the Middle Latin mater perlarum.
Throughout history, certain cultures have placed little or no value on pearls and have focused instead on luminescent mother-of-pearl from mollusk shells. Before the 19th century, Japanese shell divers who found pearls apparently did not bother to keep them. Polynesian children are said at one time to have used pearls as marbles. These and other peoples harvested pearl oysters for their shells, using the mother-of-pearl for decoration. Abalone was also popular with many groups, including those in the Americas: people ate the flesh of the mollusks and used pieces of colorful abalone shell as inlay on carved objects made of wood, ivory and bone.
Archaeologists have found that in the tombs of Sumerian royalty had many ornaments and even sometimes the entire lyre was inlaid with mother of pearl. Images of dragons playing with a pearl like object are very common in Asian art.
Here is a photo of silver ring with white mother of pearl:
Check out more jewelry with mother of pearl.