Sado Island Gold Mine — The Shogun’s Gold, Dug by Hand and Minted on the Same Island

History

Gold on Sado enters the written record as sand, not as rock. The Konjaku Monogatarishū, compiled in the twelfth century, tells of a prospector who crosses from Noto and comes back with gold wrapped in cloth; the story is attached to Nishimikawa, the placer workings that are treated as the oldest of their kind on the island. Hard-rock mining came later and from outside. The Tsurushi silver mine was discovered in 1542 and became the largest silver working on Sado, with more than six hundred traces of excavation recorded; engineers from the Iwami silver mine brought cupellation, the lead process that separates silver from ore, and that knowledge made the Aikawa gold veins workable.

In 1601 Tokugawa Ieyasu took the island under his direct control and began developing Aikawa in earnest. Ōkubo Nagayasu arrived as magistrate in 1603, an office building followed in 1604, and by 1621 koban coins were being struck on Sado. In the Genna and Kan’ei years of the early seventeenth century the mines are estimated to have produced more than 400 kilograms of gold a year, with some 10,000 kan — about 37.5 tonnes — of silver delivered annually to the shogunate. Sado is the only place in Japan where the whole chain, from ore to minted coin, happened on one site, and more than a hundred picture scrolls record the work.

What the property is now celebrated for is what happened next: because Japan’s seclusion policy kept foreign machinery out, mining, smelting and refining stayed manual, and manual technique kept being refined rather than replaced, for some 250 years while other countries mechanised. The drainage problems of the later Edo period were met with tunnels, among them the Minamizawa adit of 1696. The Meiji government took the mines over in 1868, sent Western engineers in 1869, and by 1877 had sunk Japan’s first Western-style vertical shafts, the Ōdate shaft among them. Mitsubishi bought the mine in 1896 and electrified it; production peaked around 1940 at roughly 1,500 kilograms of gold and 25 tonnes of silver a year. The Tsurushi mine closed in 1946 and the workings were suspended in 1989.

The 2024 inscription carried a dispute with it. Japanese recruiting of Korean workers for the mine began in February 1939, when the Korean peninsula was Japanese territory, and about 1,200 came between then and March 1945; Korean sources describe the labour as forced, and Japan’s ambassador to UNESCO acknowledged the forced-labour history in 2015. An exhibition on working conditions was installed for the nomination, and critics have argued that it does not name forced labour.