Before Qin unified the six countries, the shapes of coins in different countries were different. What do you know? Before the Qin dynasty unified the six countries, the currencies of various countries had different forms, such as shovel currency, knife currency and ring currency. In 22 1 year BC, the Qin dynasty unified the world, stipulating that the domestic and foreign currencies were the national common currency, which was the oldest unified currency in China. Coin is the best embodiment of social and economic development at that time, and it is also the prosperity and end of the dynasty at that time.

After Qin unified the whole country, the unified currency was called Qin Banliang. The currency is "semi-bright" in the outer circle, with no internal and external contours, flat back and no words; The words "half beam" on the seal are listed on both sides of the borehole. After Qin unified the whole country, the unified currency was called Qin Banliang. From the second year of Qin Huiwen (336 BC) to the last year of Qin Dynasty (206 BC), the production of forbidden Qin money (including writ period) lasted 130 years. In the early Western Han Dynasty, the old copper coins of the last vassal state of the Six Kingdoms were abolished and improved on the basis of the semi-Liangqin copper coins in the vassal state period. The coins with round square holes and Qin and semi-Liang dynasties swept the country, ending the chaotic state of different shapes and weights of ancient Chinese coins.

The square hole represents the place and the outer circle represents the sky. "Fiona Fang Cave" symbolizes the ancient view of the universe from the sky and the earth (this is a generally accepted view, but some people think that Fiona Fang Hole is the need of production and processing, the need of convenient handling, circulation and storage, and a more scientific system formed in continuous practice). Qin Banliang's round hole coins swept the country, ending the chaotic state of different shapes and weights of ancient Chinese coins. It was discovered in thousands of years of history, so this coin should be considered as the ancestor of some copper coins.

***2 18. Semi-Liang Qian is the oldest unified copper coin in China. According to time, it can be divided into: pre-Qin period, the king of Qin and the first emperor Ying Zheng, late Qin and early Han. In the first year of Jianyuan (BC 140), Emperor Wu of the Han Dynasty issued three Thai baht coins, which were as important as words. This is a measure aimed at restoring the consistency between the face value of copper coins and the legal weight. This was improved on the basis of Qin Banliang coins in the compulsory state period. The four-hole Qin and semi-Liang coin circle swept the country, ending the chaotic state of different shapes and weights of ancient Chinese coins.