In the early days of mining, prospectors used an arrastre, like the one that is part of the Arizona Gold Mining Experience at Cave Creek Museum.
According to Greg Barnhart, mining expert and member of the museum’s Dream Team, says an arrastre is a primitive mill for grinding and pulverizing gold or silver ore. Typically, arrastres feature two or more drag stones placed in a circular pit paved with flat stones, and connected to a center post by a long arm or beam. With a horse or mule providing power at one end of the arm, the stones were dragged slowly around in a circle, crushing the ore.
“The Spanish introduced arrastres to the New World in the 16th century,” sys Barnhart. “The word “arrastre” comes from the Spanish language arrastrar, meaning to drag along the ground. Most arrastres were fitting for use in small or remote mines, since they could be built from local materials and required little expense to operate.”
To extract gold ore, the gold was typically recovered by amalgamation using mercury (quicksilver). The miner would add clean mercury to the ground ore, continue grinding, rinse out the fines, then add more ore and repeat the process. At cleanup, the gold amalgam was carefully recovered from the low places and crevices. The amalgam then was heated in a distillation retort to recover the gold. The mercury was saved for reuse.
”The arrastre in the museum’s Arizona Gold Mining Experience demonstrates how difficult it was to mine for gold early in the century,” adds Barnhart. “Miners worked extremely hard in harsh conditions for the little bits of gold they were able to capture.”
The 54-year-old museum’s mission is to preserve the artifacts of the prehistory, history, culture and legacy of the Cave Creek Mining District and the Cave Creek/Carefree foothills area through education, research and interpretive exhibits. The Cave Creek Museum is located at 6140 E. Skyline Drive in Cave Creek, Ariz. Open October through May. The museum can be reached at 480.488.2764 or cavecreekmuseum.org
