The mine, also known as the Combined Metals Mine, was first discovered in 1864 as a high-grade silver deposit. Prior to 1941, the ores were milled in Utah, which was costly to transport but in 1937 an electric transmission line was put in from Hoover Dam just for the mines of this area.
Work soon began on building a mill. The mill eventually processed over a million tons of ore before it closed in 1958. The mine is extensive and a deep, vertical one. The main 1,470 ft shaft connects with levels at 660, 840, 1200, and 1400.
The mine and mill are privately owned and in caretaker status. I’ve been lucky enough to get a private tour of the mill buildings twice.