The shape of "Yuanbao" did not exist before the Ming Dynasty. There were horseshoe-shaped gold ingots in the pre-Qin Dynasty and gold ingots in the Western Han Dynasty, which were quite different from ingots. In the Tang Dynasty, silver ingots were mostly long cubes, while in the Song Dynasty, they were waist-tied.

The silver ingots in Tang and Song Dynasties are simple in shape and can fully occupy space when stacked. However, in the Ming and Qing dynasties, it was almost impossible to give a reasonable explanation for the strange shape of this horseshoe and the ship's ingot. Now people's far-fetched argument is that the ancients used to tie money around their waists, and the ingots stood up and tied them around their waists with cloth strips, which was convenient to carry.

In the currency history of China, gold and silver were officially called "gold ingots", which began in the Yuan Dynasty. But as early as the early Tang Dynasty, when Kaiyuan Bao Tong was alive, the people read it as "opening an ingot" because of its huge and precious value. In the Yuan Dynasty, gold and silver money was called "gold ingot", which means the treasure of the Yuan Dynasty. Gold is called "gold ingot" and silver ingot is called "silver ingot", which has both political meaning and common name of gold and silver currency.

In the monetary history of China, the discovery and use of silver was later than that of gold. Experts believe that this is because silver ore is often combined with copper and lead, and smelting decomposition technology is difficult to master. Therefore, it was after Emperor Wu of the Han Dynasty that silver was used as a monetary material, and casting into various shapes as a weighing currency for payment began in the Tang and Song Dynasties.

Yuan people's understanding of silver was as early as Genghis Khan's era, when Mongolia had close trade relations with countries such as Turkestan along the Mediterranean coast, and caravan exchanges were also very frequent, using popular silver coins in the transaction; After entering the Central Plains, functions of money of Baiyin has been improved.

Although in the early Yuan Dynasty, people were forbidden to circulate and buy and sell gold and silver, it has become a common practice for people to use silver to evaluate loans, daily transactions and even pay labor remuneration. The importance of silver money is reflected in the fact that after the government established the paper money system, it used silver as capital to ensure the issuance of paper money.

References:

Baidu encyclopedia-gold ingot