Why can copper coins ward off evil spirits?

Since ancient times, copper coins have been used as tools to ward off evil spirits. The reason why copper coins are chosen as utensils is because copper coins, as a kind of currency, exercise the function of currency circulation, which is higher than the frequency of general commodity circulation. In other words, copper coins will be passed in different hands in the process of trading, which shows that people are very popular and ghosts are afraid of yin and yang, so wearing copper coins has the function of avoiding evil spirits. Therefore, the older the copper coins, the better the effect of avoiding evil spirits, and the effect of newly cast copper coins will be greatly reduced.

There is also a saying that money can communicate with God, and God has a certain deterrent effect on ghosts, so ghosts dare not approach.

Extended data:

Copper coin, ancient copper coin, refers to all kinds of square hole coins after Qin and Han dynasties, and the casting period of square hole coins continued until the late Qing Dynasty and the early Republic of China.

During the Spring and Autumn Period and the Warring States Period, with the development of commodity economy, the metal weighing currency that needs to be divided and identified in circulation gradually became unsuitable and was replaced by metal coins. Most ancient coins in China were cast in the form of copper alloy, and square hole coins (copper coins) were the most common ancient coins.

References:

Baidu encyclopedia copper coin