The Sui dynasty only cast one type of coin, a Wu Zhu with wide rim that has been found in excavations that clearly indicated that it belonged to the Sui period. The founder of the Sui had close connections in the Wei where he grew up. Peng believes that the Sui Wu Zhu was adopted from the Western Wei, because it is said in the history of the Sui, that Wu Zhus already circulated in the first year of the Sui, and that additional new coins were minted at the same time (p. 194-195).