Mine: Indiana Mine, Mass, MI

An underground copper mine consisting of two shafts between Mass City and Twin Lakes, MI in Ontonagon County. The Indiana Mining Co. was organized in 1862 and worked for three years until 1865. No copper is known to have been produced during this time. The company reorganized in 1909, but no rock was milled and the mine was abandoned. Copper and datolite can be found here. [MINDAT]