Ann: Major Porphyry Copper/Gold System, page-29

Large scale, low cost and long mine life:

The metallurgical qualities of copper porphyry orebodies make them ideally suited for large-scale, low-cost resource extraction. “The ore is inexpensive to mill and concentrate using flotation methods, heap leaching and electrowinning processes. The mines are inexpensive to operate using bulk-mining methods,” Stanley Korzeb, economic geologist for the Montana Bureau of Mines and Geology, and a research professor at Montana Tech, told the Investing News Network. Within porphyry systems the copper mineralization can extend vertically for several kilometers beyond the main base of the open pit. This vertical scale often translates to a decades-long mine lives — Chuquicamata, Bingham, Morenci and Butte are not anomalies — meaning these mines can outlive many a market cycle, taking hits that would knock smaller mines out of commission.