This collection contains one fine knife coin and one rounded coin from the Zhao (Chou) Dynasty during the late Warring States period. Is the name of large, cast, bronze. Produced by various governments and kingdoms in what is now. Ring-shaped coins, known as. , first appeared during the Warring States period (475-221 BC). The origin for the round shape with a hole is believed to have been from either the spinning wheel or the ancient Chinese jade ring known as a. The exact purpose of the. Is unknown but it may have originally been a symbol for the sky. It also seemed to have symbolized morality and official rank. This sells as a SET only.