People in China began to use cowrie shells for money about 1800 BC. But by about 400 BC, they were using bronze coins. Nobody knows whether moneyers in China thought of this idea on their own, or got the idea from West Asia, where people began using coins a few hundred years earlier.
Soon people all over China were using bronze coins as money. Traders used these coins to trade with people from other countries, too. We even find Chinese coins as far away as East Africa!
To make these Chinese coins (much bigger than real ones), shape them out of clay and then paint on the Chinese characters. Chinese coins usually had square holes in the middle so you could keep them on a ribbon or a stick.