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Tsuchihata Mine

The mine is situated on the coast of the Konigase River, a tributary of the Waga River, on the western edge of the prefecture, and it produced copper ore from the early 20th century. The discovery of an outcrop was made by Iwajiro Terui, a local villager, at Hatabira in 1900. The same year, Kyuemon Fukuda, from Senboku County, applied for an exploration permit for gold and silver ores and began gold extraction with the amalgamation process the following year. However, the operations were unprofitable, and the mine was abandoned later. Subsequently, Yoshiaki Hamamoto, a businessman from Tokyo, and others purchased the rights in 1903 and established Yugawa Gold Mine Company three years later. Despite adopting cyanide process in addition to conventional methods, the results were poor, and the company continued with exploration and excavation of Okiri Adit. In the early 20th century, the First World War caused a rise in demand for copper. Under such circumstances, Ken-ichiro Takahashi, a local villager, discovered copper ore in old workings in 1915 and began mining operations. The mine was renamed Tsuchihata Mine, and mined ore was sold to others. The following year, Tanaka Mining Co., Ltd., later Itohei Corporation, acquired the mine and commenced mine development including the construction of aerial cableways and the use of rock drills. The construction of a new beneficiation plant with the all-sliming process in 1924, which became the first in the country, especially led to an increase in production. In the peak year of 1929, the mine produced 132,786 tonnes of crude ore and 17,407 tonnes of copper concentrate, and the number of miners totaled 558. Furthermore, due to the development of new ore deposits at Uenono in 1933, the crude ore production exceeded 200,000 tonnes per year for the following five years. After the war, declining production gradually recovered in the middle of 20th century due to the purchase of Okinasawa Mine in 1950. Moreover, the introduction of new mining methods and the expansion of production equipment led to a revival of the mine's production from the late 1950s. A mining town built in Yugawa, where a hot spring emerges, had a population of approximately 3,000, comprising employees and their families. The town was equipped with numerous welfare facilities, including company houses, company bathhouses, a lecture hall, a gymnasium, a shop, and an elementary school. Although the mine was closed due to depletion of resources in 1976, wastewater treatment and the recovery of cement copper have been continuing. The remains of the beneficiation plant still stand on the mountainside.

closure in 1976