At that time, agricultural people began to use tools, shells, or jade in exchange for goods. Shells became widely popular because they are light, effortlessly transportable, and can be easily counted.
According to an excavation, there were many shells found from the Shang and Xia dynasty, and evidence proved that shells were not used until the Chunqiu period. For a long time shells played an important role in the Chinese economy, which is why there are many Chinese characters related to them.
China is the first country to use mint coins. The history of coins dates back to the late Shang dynasty and was supported by an excavation discovery.
China is also the first country where paper money was used. Its use can be traced back to the 9th century. In Europe, Bank of Sweden first issued paper money in 1661. There are now more than 200 kinds of paper money issued in different countries; the most important ones are the US dollar and European Dollar. With the rapid development of the Chinese economy, RMB are also taking an important part in world trade.