A company town built on copper, and the mountain it left behind
Clarkdale, Arizona was founded in 1912 by Senator William A. Clark — the "Copper King" — as a company town for his United Verde Copper Company smelter. Ore came down from the mines at Jerome; the smelter on the banks of the Verde River processed it from 1913 to 1953.
For forty years, the furnaces ran. By 1920 the plant produced more than 150,000 pounds of copper per day. Two great stacks — 400 and 430 feet tall — stood over the valley until the 1960s.
Everything the furnaces could not take, they poured out back. Over four decades that tailing became a mesa of vitrified slag: an estimated 20.2 million tons of it, sitting on the surface, already mined, already crushed by heat and time.
Early-1900s smelters recovered copper and left the rest. The slag still carries that legacy — iron, copper, zinc, and precious-metal values measured by modern instruments.
First mining claims filed at Jerome, four miles southwest.
William A. Clark founds Clarkdale as a planned company town; smelter construction begins.
United Verde smelter operates. Clarkdale becomes one of the most modern mining towns in the world — telephones, electricity, spring water, planned streets.
Peak output: over 150,000 lb of copper per day.
Smelter closes. The slag mesa remains — roughly 20.2 million tons.
Clarkdale incorporates as a town.
Modern XRF and fire-assay sampling of the slag begins. Results below.
