The Idarado Mine

The Idarado Mining Company was founded in 1939 through a consolidation of mining claims that included the Black Bear, Treasury Tunnel, Barstow, and Imogene mines. In June 1943, work began to extend the Treasury Tunnel below the Black Bear Mine to extract lead, copper, and zinc ore. As miners drove farther into the mountain, Idarado acquired additional properties including the Ajax and Argentine Mines. At the same time, the Telluride Mining Company acquired the Smuggler, Ansborough, Humboldt, Flat, Liberty Bell, and Pandora mines and negotiated a lease with the Tomboy Mine that gave access to the Montana, Argentine, and Tomboy mines. To improve access and remove ore, the Mill Level Tunnel was driven from the Pandora Mill. Near the end of World War II, the Idarado and Telluride mining companies connected below ground. Mineral markets in the 1950s were extremely low, forcing the companies to reorganize and sell assets. Idarado eventually acquired the entire mine and both mills and continued to develop the mines until they closed in 1978. The Red Mountain portal and the Pandora portal near Telluride are connected underground, and miners had to climb or be hoisted about 1,700 feet between the two entrances. An underground tunnel 5 1/2 miles long connects the Idarado Mine with the town of Telluride. The Idarado Mine Trestle was used to move ore from the mine to a concentrating mill on the hill below it, and after the mill was dismantled, the trestle was used to remove and dump waste rock from the mine.

Colorado · United States