Arizona Mines | Arizona Memory Project
By the 1870's, an uptick in hardrock mining yielded prodigious volumes of copper, lead, zinc, silver and gold ore. In 1912, the newly christened state of Arizona supported 445 active mines, 72 concentrating facilities, and 11 smelters; their gross value that year was nearly 67 million dollars - equivalent to 1.4 billion dollars in 2006.
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