Aes rude (Latin, "rough bronze") was a nugget of bronze used as a sort of proto-currency in ancient Italy during the gradual transition from bartering to the use of round coinage made from precious metals. The earliest surviving piece of aes rude dates from the early 8th century BC and as late as the late 4th century BC, and was cast in central Italy. It is, simply, bronze, shaped vaguely like a lumpy ingot. Only later on did it become usual to mark these lumps and, eventually, make them into a standard shape (the round, thin disk-shape still in use today).