Ancient Bronze coinage already was fiduciary money. It’s appeared in the Greek colonies around the middle of the 5th century BC, then expanded to the rest of the Greek world and took a growing part in the exchanges alongside the precious metal currency. Its beginnings seem to be partly explained by cultural transfers from non-Greek people and are related to commercial exchanges and needs mainly caused by wars. They suppose that an evolution of the conception of coinage, so far in precious metal only, previously occurred. Besides, cities renowned for their ability to fashion bronze are among the first to mint bronze coinage, what suggests considering this artifact also as a product of metallurgy, notably by analyzing its composition.