In the early years of the Western Han Dynasty, Emperor Gaozu Liu Bang gave up the right of the state to cast copper coins, and "made the people cast money" and opened up the people to make money. In fact, after years of war, the government treasury was empty and could not produce enough copper to coin and issue money. Only local forces that own copper mines are given the right to cast and issue money. Although Lv Hou recovered the right to coin, Wendi once again allowed the people to cast private copper coins. However, it is stipulated that each coin weighs 4 baht, and lead and iron are not allowed to be doped.
Those powerful officials and dignitaries can openly exploit the mountains and make money: as for the people, they also try their best to obtain copper materials and make copper coins privately. For example, "Hanshu Shihuozhi" said: "County officials often make money from many copper mountains, but the people steal them, countless, and the money is too much and light." Although it has played a positive role in resuming production and developing economy, it is even more unfavorable to economic development. This widespread phenomenon of private casting for profiteering will inevitably lead to a large number of coins with inferior craftsmen, small size and light weight, which will seriously affect the normal circulation of money and will inevitably lead to the depreciation of coins. The direct consequences of issuing this currency are soaring prices, withering people's livelihood and rapid concentration of wealth to a few people. The evil consequences brought by this policy were unexpected by the newly established Western Han government, which eventually led to the chaos of the Seven Kingdoms. It is also the fundamental reason why Emperor Wu of the Han Dynasty really made up his mind to recover the right to coin.