By Worcester P. Bong
Since the 1863 discovery of gold and other ores in the Bradshaw Mountains, the history of mining in central Arizona has been well-documented. Near the present-day town of Dewey-Humboldt, 18 miles southeast of Prescott, the Humboldt Smelter and two earlier smelters (Agua Fria and Val Verde) were built to crush and smelt ore. The smelting process extracts metals, such as gold, silver and copper, from ore by heating it beyond its melting point.
In 1876 Levi Bashford, a former Territorial official and local businessman, built the Agua Fria Smelter. Located along the Agua Fria River, the facility was a water-powered stamp mill and smelter furnace. In 1884, after the smelter burned down, the Val Verde Copper Company bought the property. In 1899 the company built the Val Verde Smelter, which included a 180-foot smokestack built by the Weber Chimney Company. Ore, primarily copper, was processed there from small mines in the area. The operating capacity of the smelter was 250 tons of ore per day.
In May of 1904, the Bradshaw Mountain Copper Mining and Smelter Company was negotiating to purchase the Val Verde Smelter. However, on September 24, 1904, a fire destroyed the smelter, but the smokestack survived. The smelter was under-insured, and the property was sold to the Consolidated Arizona Smelting Company. In 1905 the Consolidated Arizona Smelting Company started construction of the Humboldt Smelter. Completed in 1906, it could process up to 1,000 tons of ore per day. Around 1917 a brick smokestack and brick converter flue were built to improve the smelting process. Bricks for the smokestack and flue were made by the Gallup Fire Brick Company in Gallup, New Mexico.
Peak production at this smelter occurred during World War I, when copper was in high demand. As reported in the March 20, 1918, Weekly Journal-Miner, the Humboldt facility was smelting 800 tons of ore per day from two mines near Mayer. Ore was hauled by aerial trams from each mine, loaded onto railroad cars and transported twelve miles by rail to the smelter.
Between 1922 and 1927, the smelter operated intermittently as copper prices plummeted. In October of 1929, the smelter resumed operations, processing only 175 tons of ore per day. The Humboldt Smelter closed for the final time in 1937. Its equipment was dismantled and sold to a mine in Jerome. By the time World War II ended, in order to reduce the taxable value of the property, buildings were demolished. The two prominent features that remained on the site were the original 180-foot smokestack from 1899 and the brick smokestack and brick converter flue from 1917. In early 1955, the 180-foot smokestack was brought down with explosives. The most visible remaining structures on the property were the 1917 smokestack and converter flue.
On September 3, 2008, the U.S. Environmental Protection Agency (EPA) listed the Humboldt Smelter site along with the nearby Iron King Mine on the National Priorities List (known as the Superfund list). Remedial investigation (RI) sampling was completed by March 2010. The EPA identified several areas to clean up at the Humboldt Smelter, which included demolition of the remaining smokestack and converter flue. In January of 2022, the Arizona Department of Environmental Quality (ADEQ), in coordination with Tetra Tech and the U.S. Environmental Protection Agency (EPA), completed the controlled takedown of the brick smokestack and brick converter flue. Today, the smelter property is fenced and off limits to the public. In October of 2023, the EPA issued a report to plan and implement a final comprehensive cleanup for the Humboldt Smelter and the nearby Iron King Mine.
“Days Past” is a collaborative project of the Sharlot Hall Museum and the Prescott Corral of Westerners International (www.prescottcorral.org). This and other Days Past articles are also available at www.archives.sharlothallmuseum.org/articles/days-past-articles/1 The public is encouraged to submit proposed articles and inquiries to dayspast@sharlothallmuseum.org Please contact SHM Research Center reference desk at 928-277-2003, or via email at archivesrequest@sharlothallmuseum.org for information or assistance with photo requests.