Silk - soft fabric made from threads extracted from a silkworm cocoon. Initially, silk came from China and was an important commodity that was delivered to Europe via the Silk Road. The thickness of the fiber is 20-30 micrometers. The length of a silk thread from one cocoon reaches 400-1500 m. The thread has a triangular section and, like a prism, refracts light, which causes a beautiful transfusion and shine.