Tieqian

Iron cash coins (; Vietnamese: ''Thiết tiền''; Japanese: 鉄銭（てっせん）; Rōmaji: ''Tessen'') are a type of Chinese cash coin that were produced at various times during the monetary history of imperial China as well as in Japan and Vietnam. Iron cash coins were often produced in regions where the supply of copper was insufficient, or as a method of paying for high military expenditures at times of war, as well as for exports at times of trade deficits.

While the earlier recorded iron cash coins in Chinese history were Wu Zhu's (五銖, 118 BC–618 AD), the unearthing or iron Ban Liang (半兩) cash coins produced during the Western Han dynasty during the 1950s indicates that they may have been much older than first thought. The largest number of iron cash coins would be produced during the Song dynasty period as a result of a scarcity of copper and high military expenditures, among other reasons. The last government attempt at issuing iron cash coins occurred during the 1850s the under the reign of the Manchu Qing dynasty.

Iron cash coins were not exclusively produced by the Chinese, as other cash coin producing countries would also issue them under similar circumstances or by private mints. In Japan iron ''Kan'ei Tsūhō'' (寛永通寳) cash coins were produced by the Kamedo mint in the 1760s. Provided by Wikipedia