Sung currency (宋銭)
Sung currency is copper coins which were minted in China during the Baisong period. Although iron coins were also minted during the period of the Sung Dynasty (in marginal areas such as the Sichuan Province and the Shan Xi Province, the possession and use of copper coins were totally banned to prevent copper from going out to the Liao Dynasty and Xi Xia, and instead, people were forced to use iron coins), generally, Sung currency means copper coins which were the overwhelming majority.
Summary
Starting with Song Yan Tong Bao, which was minted around the founding days, every time they changed the name of an era, they minted new coins with its name, which resulted in the variations of copper coins such as Tai Ping Tong Bao, Chun Hua Tong Bao, Zhi Dao Yuan Bao, Xian Ping Yuan Bao, Jing De Yuan Bao and Xiang Fu Yuan Bao.
The mining of copper mines and minting of copper coins were nationally owned and they were conducted at the government offices, such as jusenkan and jusenin.
At first, one coin was worth one mon (or one sen) and it was called shohei sen (sho sen). However, as the financial situation of the Sung dynasty fell to inflation and got into trouble, other coins such as to gosen (equivalent to five sen) and to jussen (equivalent to ten sen) were minted. What were mainly circulated were shohei sen and to ni sen (or, ori ni sen [ori two sen]). 1,000 sen was called kan, sashi or sen. Also, when 96 one mon coins were put together on a string, they were called toshi 100 mon and were considered as 100 mon. Also, when 10 toshi 100 mon were gathered, meaning 960 mon on a string, it was equivalent to one kan (toshi one kan).
Although mint output at the founding days was 70,000 kan annually, it grew gradually and at the time of the Shenzong Dynasty (1067 to 1085) it reached 6,000,000 kan.
Circulation
The Sung currency was also used in Jin, Xi Xia, Japan and South East Asian countries, and even reached as far as Persia and African countries. As it was circulated almost all over Asia, it greatly affected the economic situation of the time. This tells us about the political influence of Chinese dynasties at that time. Meanwhile, it is said that the mint output of copper coins was already behind the country's economic scale during the Tang Dynasty and under such circumstances the further outflow of copper coins plunged the Chinese economy into chaos by causing constant lack of copper coins called 'senko'. This resulted in the issuance of bills by the dynasty and they were used in deals together with silver.
Circulation in Japan
Circulation of the Sung currency in Japan began in full in the late 12th century. In particular, TAIRA no Kiyomori was eager to trade with Sung, and a large amount of the Sung currency was imported after that. Meanwhile, in 1179 when discord between the Taira family and the Cloistered Emperor Goshirakawa deepened, Motofusa MATSUDONO and Kanezane KUJO, with the intention of the Cloistered Emperor who thought the funds the Taira family got through the Sung currency was the source of their emergence, insisted on banning the circulation of the Sung currency as 'they are not coins that (Japanese) Imperial Court issued and they are the same as Shichusen (counterfeit money)'. However, on the other hand, Kiyomori, the Emperor Takakura and Michichika TSUCHIMIKADO argued back that they should publicly introduce the currency, admitting the situation of the time. In 1187, after the Taira family had fallen, Kanezane KUJO became a regent with the recommendation of the Mikawa Province kokushi (provincial governors), MINAMOTO no Noriyori (who was a younger brother of MINAMOTO no Yoritomo so it was more like Yoritomo's suggestion), and he ordered the suspension of circulation and placed 'a ban on the Sung currency' properly in 1197. However, as its circulation rose even more in the Kamakura period, the Kamakura bakufu (Japanese feudal government headed by a shogun) changed their policies and allowed its use in 1226 and the Imperial Court, four years after that. In 1242, a trading ship that Kintsune SAIONJI dispatched to Sung brought back 100,000 kan worth of coins. After the 13th century, the currency value that silk or cloth had had was driven away by coins and nengu (land tax) was also gradually paid in coins.