Granite Mountain/Speculator Mine Disaster

The Granite Mountain/Speculator Mine disaster is considered the worst hard-rock mine disaster in the United States, with 163 people dying as a result of the fire. The disaster is remembered both for its death toll as well as the strike that ensued following the fire.

The Granite Mountain/Speculator Mine disaster near Butte, Montana, began a little before midnight on June 8, 1917, as the result of a tragic but ironic accident. The North Butte Mining Company planned to install a sprinkler system in the 3,500-foot shaft of Granite Mountain to increase safety. The system was nearly complete when one of the last steps required moving an electrical cable that was 1,200 feet long and weighted three tons. While workers lowered the cable, it slipped and fell about a thousand feet down a mine shaft. The cable was ruined in the fall, as it had stripped away the cable’s lead sheathing, revealing the oil-soaked cloth insulation underneath. Workers left the cable in the shaft and reported the incident to the assistant foreman, Ernest Sullau.

Sullau and John Collins, a shift boss, went down to inspect the damages and locate the cable. Sullau carried a carbide-burning lantern, with an open flame, and as he walked around the shaft, he set a piece of cloth on fire. Surprised, he moved the lantern back away from the burn but inadvertently set another section of cloth on fire. Sullau stayed below while Collins went above to inform the engineers of the fire.

Although the fire burned extremely hot, few miners were burned. Instead, the fire’s smoke and gas was the true threat as it spread throughout the mine as well as into adjoining mines, asphyxiating Sullau and many miners. Firefighters worked for five days to contain the fire, and it took rescuers three days thereafter to get all the survivors out. Most of those who survived were treated for smoke and gas inhalation onsite and were able to go home; the few particularly bad but still living cases were rushed to the hospital. By the time the dust settled, the community counted 168 dead.

The fire was a breaking point for the workers in Butte. Left with no unions since 1914, they went on strike and created the Metal Mine Workers’ Union. However, Butte was one of the largest producers of copper, and due to World War I copper was in high demand. As a result of the need for copper, in August the federal government deployed troops to break the strike. With federal troops on the scene adding to mounting pressures against the miners, their strike ended in December.

The fire was also particularly difficult for the miners’ families. While compensation was available, it was only given to miners who had wives or children. Otherwise, the company was only obligated to pay $75 for funeral expenses. However, many of the unmarried miners were the sole providers to their elderly parents. Miners whose family members were either not U.S. citizens or not in the country also did not receive financial compensation. Overall, only 39 of the 163 families of the dead received any non-funeral financial compensation.


Where there’s smoke
Where there’s smoke This photograph of the fire—used as a postcard—shows its effects above ground. Source: “Fire at Speculator Mine.” June 15, 1917. Courtesy of the Montana Historical Society, via Digital Vault.
Is Vernon Thompson missing?
Is Vernon Thompson missing? In this telegram to the North Butte Mining Company, Mrs. W.J. Wiley inquired about a missing miner named Vernon Thompson. Source: Mrs. W.J. Wiley, telegram to the North Butte Mining Company, June 14, 1917. Courtesy of the Montana Historical Society, via Digital Vault. Creator: Mrs. W.J. Wiley
Identified and buried
Identified and buried This letter from the North Butte Mining Company informed Mrs. W.J. Wiley that Vernon Thompson’s body had been found and buried. Source: North Butte Mining Company to Mrs. W.J. Wiley, June 14, 1917. Courtesy of the Montana Historical Society, via Digital Vault. Creator: North Butte Mining Company
Memorial to the miners
Memorial to the miners This plaque specifically honors those miners killed in the Granite Mountain/Speculator Mine disaster as part of a broader memorial to the miners. Source:

“Speculator Mine Monument.” Banjodog (pseud.), February 8, 2015. Via Wikimedia Commons (CC BY-SA 3.0).

Creator: Banjodog (pseud.)


Granite Mountain Mine Memorial, Alexander Street, Butte, MT 59701 | This marks a memorial site for all mining deaths in Granite Mountain/Speculator. In addition to 168 miners listed as victims of the 1917 fire, the monument honors 2,500 miners total who lost their lives due to mining-related causes.


Megan Wagner, Northern Arizona University, “Granite Mountain/Speculator Mine Disaster,” Intermountain Histories, accessed June 23, 2024,