Southwest of Camp Verde along Salt Mine Road are some low, bright white mounds — evidence of rock salt deposits, found in bands up to 60 feet thick in the Verde Formation, which formed millions of years ago from evaporating freshwater lakes.
The salt was gathered here for millennia by Indigenous peoples including the Sinagua, Hopi and Yavapai. When Fort Verde was established in 1871, soldiers and settlers were also thought to have quarried the salt - partly for their own consumption, but more so for livestock.
During the 1920s the Arizona Chemical Company began commercial open pit mining at the site. Around 75 people, including Apache miners, produced nearly 100 tons of ‘salt cake’ per day, briefly making Camp Verde the most productive salt mine in the country.
In the early 1930s when underground tunnels were dug to follow some especially rich bands of salt, miners stumbled across four ancient tunnels, where they found woven yucca sandals and matting, shell bracelets and a reedgrass cigarette, which were carbon-dated to the Sinagua era.
Verde Valley salt mining ceased in 1933 when high-purity German salt hit world markets. More recent attempts to revitalize the mine have failed – because Camp Verde salt is 7% below the 99% purity level required by modern standards.
Today a few decaying timbers and rusted bits of old machinery are all that remain to mark the site of one of America’s oldest underground salt mines.
This Earth Note was written by Diane Hope and produced by KNAU and the Sustainable Communities Program at Northern Arizona University.
