Top copper miner's output slump adds to worry on metal shortfall

A tight copper market may be set to get a lot tighter, if a report this week from the world's biggest miner of the metal is any indication.

Santiago-based Codelco posted the lowest quarterly copper production this year in the third quarter, according to Chile copper agency Cochilco. The company reported declines across all of its mines in September as ore grades fell an average of 5 percent in the first nine months of the year.

The decline in ore grades compounds supply troubles after a commodities price slump that ended in 2016 made miners skittish about expanding their operations in Chile, the world's largest copper supplier. At the same time, mounting trade tensions are prompting mining companies to delay big expansion projects amid uncertainty about the outlook for demand.

The International Copper Study Group forecasts a production deficit of 90,000 metric tons this year, more than double the shortfall forecast in April. Lower grades were partly offset by a 2 percent increase in metal recovery, but output for the first nine months of the year was still 41,000 tons lower than in 2017, Codelco said in an emailed response to questions.

"Companies need to cover themselves and generate investment programs to expand their capacity and mitigate the ore-grade decline," Cesar Perez-Novoa, an analyst at BTG Pactual in Santiago, said by phone on Thursday. "Otherwise, the depletion of resources over the next ten years will be high."

Codelco is investing $36 billion over the next ten years to upgrade its aging mines to compensate for the decline in copper grades and to maintain production levels, Perez-Novoa said.

(By Laura Millan Lombrana)