Gold and Silver Mines
Sado Island, located off the coast of Niigata, was a booming center of gold and silver mining during the Edo period (1603–1868) when mines on the island employed thousands of workers from throughout Japan. The mines were in operation until 1989 and produced a total of 78 tons of gold over the centuries—the second-largest haul in Japan.
The first record of mining for precious metals on Sado is from 1185, but production did not reach its peak until the seventeenth and eighteenth centuries. Silver was discovered on Sado Island at Tsurushi and was mined there from 1542 to 1946. From 1601, one of the main gold mines was Dohyu no Warito, a mountain excavated so heavily that it was literally split in half.
The Tokugawa shogunate, which ruled the country during the Edo period, seized control of the mines and used the gold to make coins, mainly the oval koban that were used as currency throughout the realm. The shogunate sent magistrates to Sado to oversee the mines, who reported back to Edo (present-day Tokyo) using scrolls filled with detailed illustrations that explained the mining and production processes. Around 150 of these scrolls have been found in Japan and abroad, and are valuable sources for understanding traditional mining practices.
One of these traditional practices is the placer style of mining called onagashi, in which water is used to wash away sand and lighter debris from the heavier particles of gold. The traditional mining techniques were used until the end of the Edo period, by which time these methods were already antiquated and mining began to decline. The mining industry recovered after Japan opened its doors to foreign influence and began to introduce outside technology, including modern mining techniques.
The history of gold and silver mining is still visible on the island today. Many of the terraced rice fields built on hillsides near the main mining center of Aikawa to feed the growing population during the height of the gold rush remain in use. Structures such as the Kitazawa Flotation Plant, where Western-influenced technology was used to extract gold from ore, still remain standing.
Visitors can learn about this extensive history at Kirarium Sado in Aikawa, an information center detailing the history of mining through videos and other exhibits, and at the Sado Kinzan Gold Mine Historic Site, where they can enter mining tunnels preserved as they were during the Edo period and Meiji era (1868–1912). Visitors can also try their hand at onagashi mining where it began at Nishi-Mikawa, south of Aikawa.