Vietnamese cash
The Vietnamese cash (chữ Hán: 文錢 văn tiền; chữ Nôm: 銅錢 đồng tiền; French: sapèque), also called the sapek or sapèque, is a cast round coin with a square hole that was an official currency of Vietnam from the Đinh dynasty in 970 until the Nguyễn dynasty in 1945, and remained in circulation in North Vietnam until 1948. The same type of currency circulated in China, Japan, Korea, and Ryūkyū for centuries.