Ikuno mine, Ikuno-machi, Asago-gun, Hyogo Prefecture, Kinki Region, Honshu Island, Japan

A silver mine that was first worked in 807 AD. Large scale exploitation started in 1542, using traditional methods. The Japanese government hired a French mining engineer, Francois M Coignet, to modernize the mining methods in 1868. The Mitsubishi conglomerate acquired the mine in 1896. Mining ceased in 1973, by which time the galleries had penetrated several square kilometers of ground at depths up to 1 km. Mostly flooded by 1987.
Highly telescoped xenothermal veins are hosted in Tertiary sediments and volcanics overlying Paleozoic and Mesozoic formations. Although in ancient times silver was the only metal of interest, in more modern times this mine produced a large range of other metals too, including Cu, Zn, Pb, W, Sn, As, Au, Bi, Co.
Features the Senju-hon vein, Chuo shaft, Kanagase deposit (qv), Tasei deposit (qv).
Mitsubishi Corp. still maintains a silica plant here, and the museum with the corporation's excellent mineral collection, and one section of the Kanagase deposit is open for guided underground tourism.