Zinc Thien Minh Thong Bao coin

Thuan D.Luc
USA, 17-May-98
Reason to cast non-copper coin
in Southern region in 17th Century

          Nguyen Lord ruled the Inner region since 1558. The region did not produce copper. Lack of the base material to cast coin, the Southern Nguyen rulers required a continuous supply of copper.

          In the 17th century, when the Japanese ships or Chinese ships from Fujian and Kuang-Tung came with red copper, the captain must declare the amount of copper and sell it to the officials of Nguyen Lord. The traders could only buy what was left. Also, strings of Japanese cash coin were served as the base currency of the region were imported in large amount by the Dutch.

          In the 18th century, copper coins in the South became scarcer and scarcer due to several reasons:

  • Asian trade declined because Japan and Europe removed themselves from the unfavorable trade system,
  • the Japanese government restricted the copper export in 1717,
  • people melted down copper coins to make utensils,
  • and the most important one, Nguyen Lord realized that the cost of casting copper coin was unfavorable for the Court.
          The Lord, Nguyen Phuc Khoat (1738-1765) accepted the suggestion of Hoang, a Chinese, to buy tutenag from the Dutch to cast coin. Tutenag (zinc) was in Chinese called 'white lead', in opposition to real lead ('black lead'). The Lord bought tutenag at 14 quan for 60 kilograms and cast 48, 49 quan from it, which represented a big profit.


          Also Nguyen removed the ban against private individuals casting coins. There were more than one hundred foundries established to cast coin by the rich people. Initially the zinc coinage was convenient to both officials and the common people. Therefore the court began to store copper coins and not to issue them.

          And then, people began to mix black lead and cheaper substances, more and more, for profit. The coin was also smaller and thinner. The zinc coin dropped dreadfully in value. Initially in value, 1 zinc coin = 1 copper coin, but finally 3 zinc coins = 1 copper coin. Moreover people rejected zinc coins.


          The book PHU BIEN TAP LUC ('Miscellanous records in the border area') written by Le Quy Don in 1776 recited:

    'There was one kind of coin called Thien Minh Thong Bao, which had black lead mixed in and became very fragile. people refused to accept it because of its ugliness; therefore the trade did not go smoothly, coins were not circulated well'.