江戸中期の享保年間に会津藩政下において銅鉱の採掘と製錬が行われたと伝えられ、山腹には往時の旧坑が残ります。 1874 年(明治 7 年)に津川の資産家 平田次八郎が借区権を取得しますが、数年後に休山を迎えました。 その後、1902 年(明治 35 年)に新発田の寺田助松が蛍石の採掘中に銅鉱床を発見し、後に採掘権を取得します。 1906 年(明治 39 年)に五泉の実業家 小出淳太が権利を譲り受け、本格的な開発に取り組みました。 阿賀野川支流の五十母川を挟んだ両岸では鉱山事務所と製錬所が建設され、全長 1,800 m の索道によって上流に設けられた選鉱場と接続されます。 鉱石は坑内から選鉱場まで鉱車を用いて運ばれ、手作業による破砕と選別を経て索道で製錬所へ送られました。 1913 年(大正 2 年)の出鉱量は 16,791 t、産銅量は 305 t に上り、従業員数は 352 名を数えました。 同年に製品輸送を目的として岩越線(後の磐越西線)に五十島駅が開設され、1917 年(大正 6 年)に年間 686 t の産銅量を記録して最盛期を迎えます。 一方、北隣の葎澤坑では 1906 年(明治 39 年)に亜鉛が試掘され、後に亜鉛電気製錬株式会社が小規模に操業を行いました。 1919 年(大正 8 年)国内における銅相場の下落から、三井鉱山が譲渡を受けて探鉱を開始しますが、有望な鉱床は発見されることなく閉山を迎えます。 終戦後、隣接する五十島鉱山では蛍石の採掘が盛んに行われ、1963 年(昭和 38 年)の五十島鉱山閉山まで持倉の施設跡は貯鉱場として利用されました。 周辺には製錬後の鉱滓から造られるカラミ煉瓦を用いた鉱山事務所などの施設跡が今も残ります。

1920 年閉山

Mochikura Mine

In the administration of the Aizu Domain, copper mining and smelting were performed from the first half of the 18th century, and old workings of the time remain on the mountainside. Although Jihachiro Hirata, a wealthy person in former Tsugawa Town, acquired leasehold rights in 1874, the mine was abandoned several years later. In 1902, Sukematsu Terada in former Shibata Town discovered copper deposits during fluorite mining and later obtained permission for copper mining. Subsequently, Junta Koide, a businessman in former Gosen Town, inherited the rights in 1906 and initiated a full-scale development of the mine. Later, a mining office and a smelter were built on both banks of the Isomo River, a tributary to the Agano River. Then an aerial cableway with a length of 1,800 meters connected the smelter to a beneficiation workshop on the upper reaches of the river. Mine cars carried ore out of the mine to the workshop, where the ore was manually crushed. Then the sorted ore was transported to the smelter by aerial cableway. In 1913, the mine produced 16,791 tonnes of crude ore and 305 tonnes of copper and had 352 employees. The same year, Igashima Station on the Gan-Etsu Line, later the Ban-Etsu West Line, opened with the purpose of transportation of products. In the peak year of 1917, the mine produced 686 tonnes of copper. Meanwhile, exploratory drilling for zinc was performed at Mugurasawa to the north of the mine in 1906, and later Zinc Electric Smelting Co., Ltd. operated on a small-scale. The mine was transferred to Mitsui Mining Co., Ltd. in 1919 under the effects of a decline in the market price of copper, and mineral exploration began. However, the operations could not bring results, and the mine closed the following year. After the war, neighboring Igashima Mine produced fluorite and utilized the old facilities of Mochikura Mine for ore storage until its closure in 1963. The remains of the facilities built of slag brick can be found even now.

closure in 1920


Igashima, Aga Town, Higashi-Kanbara County, Niigata
copper, zinc, silver

坑口は製錬所の南方、五十母川上流の持倉沢右岸に集中し、沢沿いには採鉱事務所や選鉱場が設置されました。 鉱床は本山をはじめ、東華、北星、光盛、山神などの鉱脈群からなり、北隣の葎澤、虚空蔵は後に葎澤鉱山として稼行されます。 明治末期より近代技術の導入が進められ、選鉱を経た鉱石の運搬は人足から索道へ、製品となる粗銅の輸送は舟運から鉄道へと切り替えられて生産量を伸ばしました。

The mine entrances are located on the right bank of the Mochikura Stream to the south of the smelter, and mining facilities, such as a working office and a beneficiation workshop, stood on the stream bank. The ore deposits of the mine had several groups of ore veins, such as Honzan, Toka, Hokusei, Mitsumori, and Yamagami. Meanwhile, Mugurasawa and Kokuzo deposits to the north were worked as Mugurasawa Mine. The introduction of modern technology from the early 20th century led to an increase in production, which included the ore transportation by aerial cableway and the crude copper shipment by railway.

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The present state
持倉鉱山-鉱山事務所 持倉鉱山-鉱山事務所 持倉鉱山-鉱山事務所 持倉鉱山-鉱山事務所 持倉鉱山-鉱山事務所 持倉鉱山-鉱山事務所 持倉鉱山-鉱山事務所 持倉鉱山-鉱山事務所 持倉鉱山-鉱山事務所 持倉鉱山-鉱山事務所 持倉鉱山-鉱山事務所 持倉鉱山-鉱山事務所 持倉鉱山-鉱山事務所 持倉鉱山-鉱山事務所 持倉鉱山-鉱山事務所

Photographed in 2004
Printed in 2005