From 1689, China_s imports of Japanese copper increased t considerably and the annual consumption of copper by the central mint reached 39,000 piculs (1 picul = approx. 60 kilograms). The central mint had relied on private merchants for the procurement of copper, but from 1699 this role was transferred to merchants in the employ of the bureau of internal affairs??. (Private merchants, however, were not excluded from trade with Japan.) For almost forty years from 1684 to 1723, Ch_ing China depended entirely on Japan for the copper used for minting coins. All of the 40,000 piculs of copper consumed annually by the central mint came from Japan.
Japan could not respond indefinitely to this massive demand for copper from China. Eventually, in 1715, Arai Hakuseki issued the Sh_oku Shinrei (New regulations on ships and trade), which permitted only Chinese possessing a shimpai (a certificate of permission to visit Japan issued by the Nagasaki magistrate_s office) to conduct trade with Japan and limited the amount of copper that could be exported. On the shimpai, the name of the current era in Japan (Sh_oku) was written. However, this obligation to recognize to the other country_s calendar system placed the Chinese in the position of a subject, which ran counter to the natural order of things in Ch_ing China. For this reason, all of the shimpai were confiscated at Ningbo??. After that, Chinese ships did not come to Japan for two years.
But necessity is the mother of invention. In 1717, the Ch_ing government made the high-handed decision to interpret the shimpai as a commercial procedure that had no political meaning. The confiscated certificates were returned to the merchants, eight provinces_Jiangsu, Anhui, Jiangxi, Fujian, Zhejiang, Hubei, Hunan and Guangdong_were ordered to procure copper, and public merchants were ordered to secure 44,352 piculs of copper per year. However, the merchants refused to purchase copper whose price had been raised in accordance with the export regulations imposed by the Tokugawa shogunate, and were consequently unable to provide the Chinese government with the copper it required. Faced with this grave situation, the Ch_ing government considered various measures for the procurement of copper, including the use of copper from a mine discovered in Annam in 1722, but finally decided to develop copper mines in the mountainous Yunnan region far south of Beijing. Even so, Japanese copper continued to be imported, accounting for more than half of China_s copper coin production.
However, the yield from the Yunnan copper mines steadily increased and in 1738?? the central mint finally succeeded in procuring from it the required 40,000 piculs. In 1741, the amount of copper transported from Yunnan to Beijing reached 63,000 piculs. Eleven years later, the weight of the coins was also raised and in 1773 the amount of money produced by the mint increased. This led in turn to a decrease in the value of copper coins, forcing the Government to reduce production. The Japanese copper trade was finally no longer of importance to China.
China was thus highly reliant on Japanese copper at the beginning of the Ch_ing dynasty, the Ch_ing mint being particularly dependent on copper from Japan in the first quarter of the eighteenth century. Although China subsequently succeeded in achieving copper self-sufficiency through the development of the Yunnan copper mines, it had depended on Japanese copper for more than one century. The copper trade was the most important factor governing trade between China and Japan. Although the Chinese government kept out the Japanese through its exclusion policy??, it gave preferential treatment to Chinese engaged in trade with Japan. It is particularly significant that the Ch_ing government gave approval to trade with Japan as a special category of commercial activity that was not part of the tribute system. From China s viewpoint, trade under a world order that centered around China was conducted in the form of the tribute system, which meant that other countries had to accept the use of the Chinese calendar system when conducting this tribute trade. In the case of the Shotoku Shinrei, however, the Chinese entered into an inverted relationship with Japan in which they used certificates marked with Japan_s era name. From the Chinese standpoint, this meant giving approval to trade with Japan in a form that deviated from the official tribute trade.
