In the inadvanced science and technology ancient, the formation of the pearl is god’ s gift which is incredible for people. According to the legend, pearl is condensed by the essence of the morning dew. After sucking a drop of morning dew for some time, the shell will generate glittering and translucent pearl. If sucks rain drop, it will form dim pearl. If it is sunny weather, the pearl will be white and beautiful. If encounters lightning, the shell will close quickly thus it is impossible to form pearl. Until 1600, the French scientist Rene Reaumur cut it into thin slice and observe it in the microscope, he found that pearl is a kind of material formed by the layer stack which is similar to the structure of shell. In 1671, scientists found that pearl is formed because foreign body enter into the body of molluscs accidently and the molluscs produce discomfort and secrete substances and package it. So somebody said:” pearl is the tear of oyster, her formation is along with pain and new life.”