Pearls online puzzle
Pearls, as well as mother of pearl,consist of calcium carbonate and conchiolin. They are formed within the soft tissue of mussels in reaction to a foreign substance that got into their shells. Ever since they have been widely used in jewelry, people began to use cultured pearls. Such pearls are produced by placing grains of sand in the shell of mollusk. Pearls have been considered extremely valuable jewelry for centuries. They are used in the production of necklaces in the form of strings, or they can be set in gold and silver. Pearls have inspired generations of painters, writers, poets and musicians. They are also associated with some superstitions – e.g. it is believed that you should not give them as a gift nor wear them for the wedding, because they will bring tears and misfortune.