Zhiqian
[2] and Shangqian (賞錢, "Tip money") which is a term used to refer to cash coins that were small, thin, and very fragile (comparable to Sizhuqian) that were used to pay the wages of employees of the imperial government (including the mint workers themselves) and was one of the most commonly circulating types of cash coins during the Ming dynasty among the general population.
[2] The design of the standard Chinese cash coin was round, while it had a square centre hole that allowed them to be strung together.
[4][1] The composition of the Yongle Tongbao was generally 63–90% copper (Cu), 10–25% lead (Pb), 6–9% tin (Sn), and 0.04–0.18% zinc (Zn).
[5][6] The Yongle Tongbao cash coins were notably not manufactured for the internal Chinese market where silver coinage and paper money would continue to dominate, but were in fact produced to help stimulate international trade as Chinese cash coins were used as a common form of currency throughout South, Southeast, and East Asia.
[3] The casting of these new Xuande Tongbao cash coins was divided between the two Ministry of Public Works mints in both capital cities.
[3] Furthermore, Xuande Tongbao cash coins were also produced at the branch mints in Zhejiang, Jiangxi, Fujian, and Guangdong.
[3] Despite the government preferring paper money over copper-alloy cash coins, the Chinese market had a high demand for them, this demand would stimulate an overproduction of forgeries that inundated the markets of Ming China, often these forged cash coins were cast in such miserable quality that a single real Zhiqian could buy 300 fake ones.
[9] However, Schjöth noted that the proposal to also cast 95,000,000 strings of these 9 earlier reign titles might not have actually been adopted and that these cash coins were local and Japanese forgeries.
[10] In the spring of 1572, the Ming dynasty government once again resumed the production of standard cash coins at the Beijing and Nanjing mints.
[10] It did not take long for the mints to be opened in Yunnan, Shanxi, Shandong, Henan, Shaanxi, Jiangxi, Fujian, and Huguang, these Zhiqian all weighed 1.3 qián.
[1] Chinese people at this point started to refrain from using copper-alloy cash coins and the markets preferred the usage of silver ingots instead.
[1] In the year 1622 the Ministry of Revenue established its own mint in Beijing, this was done to help finance the continued rising cost of fighting the Manchu invasions.
[1] The obverse side of the standard cash coin would always contain the current reign era name with "Tongbao" (通寶) inscribed on it.
[15] The two imperial mints in Beijing were the only places where official standard cash coins were manufactured during the early years of the Qing dynasty period.
[15] This would mean that the official government conversation rate was set as zhé yín yì lí qián (折銀一厘錢), which was proof that silver was of continuing importance as a currency of account.
[18] In the year 1867 the imperial government issued an unsuccessful edit for all central and eastern provincial mints to cast Zhiqian with a weight of 1 qián to be transported to Tianjin to help alleviate copper shortages in Beijing.
[20][16] The standard Xuantong Tongbao (宣統通寶) cash coins produced at the Ministry of Revenue mint between the years 1909 and 1910 had a weight of 6 fēn and were both cast and machine-struck.
