Lead cash coins (; Vietnamese: Duyên tiền; Japanese: 鉛銭 (なまりせん); Rōmaji: Namarisen) are a type of Chinese, Japanese, and Vietnamese cash coin that were produced at various times during the monetary history of imperial China, Japan, and Vietnam. Typically cash coins produced in China between 300 BC and 1505 AD were made of bronze and those produced after 1505 AD were made of brass. But, like with iron cash coins, at times when copper was scarce government authorities would produce lead cash coins to supplement the money supply and maintain market liquidity.
The production of lead cash coins predominantly happened in regions where large quantities of lead were mined, namely southern China and the Tōhoku region in northern Honshu.
China is the first country in the world to issue lead coins, though when the first lead coins were produced remains controversial as it is commonly believed that the first lead coins in the world were the small Kaiyuan Tongbao (開元通寳) cash coins produced during the reign of King Wang Shenzhi of the Min Kingdom (Fujian) in 916. However, some claim that the production of lead coins was actually started a millennium earlier during the Zhou dynasty period. It is therefore taken that 916 is the earliest use of lead for the regular production of cash coins, while the lead Yi Hua (一化) coins from the State of Yan, ant-nose money from the State of Chu, and Ban Liang (半兩) cash coins dating from the Qin to the Western Han dynasties are in fact irregular uses.
Lead cash coins were also produced in what is today Indonesia by groups of Overseas Chinese living in the archipelago. The production of lead cash coins in Indonesia happened alongside tin and copper-alloy cash coins.
Overview
Iron cash coins and lead cash coins were often used in cases when there was an insufficient supply of copper. Because of how soft lead is, most lead cash coins that are found today tend to be very worn.
Lead cash coins have only been produced at a few times in the monetary history of china, mainly during the Five dynasties and Ten kingdoms period. In some cases the usage of certain types of materials to produce cash coins are only more recently discovered due to the lack of historical records mentioning them. In some cases modern economic historians mention that they existed but don't go into much detail about them, for example Peng Xinwei mentions that lead and iron cash coins but doesn't mention much about them, only writing that the King of Chu was advised to use iron and lead because it was available in large amounts. It has only been since more recent times that the fact that the Song dynasty had attempted to produce lead cash coins been discovered. Because of this almost no Chinese coin catalogues list their existence while they have mentioned in works such as the Meng Guohua: Guilin Faxian Qian Xi Hejin Qian. Zhongguo Qianbi No. 3. 1994 (Vol. 46.) which deal with the topic.
Besides official coins, counterfeit cash coins would often employ official inscriptions, like Yongzheng Tongbao (雍正通寳), but be made entirely out of lead.
Lead cash coins from southern China were successful outside of China, as the Southern Han Kingdom often exported its lead money to other countries, especially those in what is now Indonesia.
Han dynasty
In a 2005 article in the numismatic journal Xinjiang Numismatics (新疆钱币), it was reported that a number of lead cash coins dating to the Western Han dynasty period were uncovered in a small village in the Ningxia Hui Autonomous Region.
Tang dynasty
After the An Lushan Rebellion, to reduce costs and increase the hardness of coins, the imperial court added more and more lead to alloys of cash coins. During the late Tang dynasty period, some Kaiyuan Tongbao cash coins contained more than 50% lead.
Between 1982 and 2002 the numismatic researcher Qian Boquan (钱伯泉) collected over 5 lead Dali Yuanbao (大曆元寳) cash coins on the Ürümqi coin market. In a 2002 article in the numismatic journal Xinjiang Numismatics (新疆钱币), Qian Boquan reported that these lead Dali Yuanbao vary in size and weight. They range from having a diameter of 26 to 29 millimeters, a thickness of 4 to 5 millimeters, and a weight of 5.7 to 7.8 grams. The obverse and reverse of each cash coin is filled with a yellow-white alkaline patina.
Small amounts of lead Kaiyuan Tongbao cash coins were discovered in coin hoards dating to the reign of Emperor Wuzong.