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Newmont Mining Corp. has begun producing market-ready copper from its Phoenix mine south of Battle Mountain.
Newmont had been producing copper concentrate as a byproduct of gold mining at the Phoenix mine, where 180,000 to 200,000 ounces of gold and 30 million to 35 million pounds of copper are produced each year. The copper concentrate previously was sent to third-party smelters as a base feed to be refined into pure copper for market use.
Newmont over the past few years invested $175 million in additional infrastructure to leach copper from waste rock that was scattered between the ore zones at Phoenix and expects to deliver as much as 25 million pounds of copper cathode, or large plates of copper, to market during the life of the Phoenix mine.
Newmont has been working on the copper leach project since late 2006, says Doug Livermore, regional project director for Newmont’s North American region. Newmont is using a weak sulfuric acid solution to dissolve the copper from the ore. The end result after processing is a high-quality copper that can be used by brass makers or for copper tubing and cabling.
“As our knowledge (of the ore body) increased we knew we had some amount of this resource. As we continued to explore the deposit and grow it we were able to identify enough to make it economically viable,” Livermore says.
Cost to produce the copper cathode is projected to be $1.75 to $2 per pound. The per-pound selling price for copper is averaging between $3.25 and $3.30, Livermore says.
Livermore likens the ore body at Phoenix to a soup with many ingredients. Some areas have a lot of gold, others contain copper, while some areas have both and still other areas are considered waste.
“It actually was waste rock, and we would have had to move it anyhow in support of current mining activities for copper and gold resources,” Livermore says. “It would be treated as waste, but because we have identified enough of it we invested in leaching facilities and a plant to produce between 20 and 25 million pounds of copper over the life of mine at Phoenix.”
The copper leach project at Phoenix also builds upon Newmont’s strategy to increase its presence and capabilities in the copper segment of the mining industry, Livermore says. A primary challenge associated with the project was the amount of work that needed to be done with federal regulators and the Bureau of Land Management.
“Copper production in Nevada in the state is new at some levels,” Livermore says. “We have a history of copper production, but this new leaching project required a lot of work with regulators in a collaborative setting to be able to get the facility permitted and put into production.”
