Underground copper mine operated circa 1909 - 1944
The first major accident at the Granite Mountain Mine occurred on October 19, 1915, when part of a dynamite shipment of was ignited accidentally on the surface next to the Granite Mountain shaft, killing 15 miners.
On June 9, 1917 a spark from a carbide lamp ignited the oil soaked insulation of a damaged cable. Smoke from the fire quickly spread throughout the Granite Mountain and into the adjoining Speculator Mine. It became the deadliest accident in the history of American hard rock mining. One hundred sixty eight miners lost their lives. Sixty five of these were burnt beyond recognition and were buried in a mass grave at Mountain View Cemetery.