Chilean state copper miner Codelco saw a 1.9 percent drop in its output in 2018, at 1.8 million tonnes, while production at the world's largest copper mine, Escondida, shot up 34 percent in the same year, Chile's copper commission said on Thursday.
Codelco was affected by a natural decline in ore grades, an issue it is seeking to reverse with a major program of upgrades. Production at Escondida, controlled by BHP Group Ltd, rose to 1.24 million tonnes because of a low base of comparison due to the impact in 2017 of a workers strike that lasted for 44 days.
Meanwhile, Chile's second-largest copper mine, Collahuasi - a joint venture between Glencore Plc and Anglo American Plc with Japanese firms - recorded growth of 6.7 percent in its production to 559,200 tonnes last year.
Last year, Chile's total copper production rose by 6 percent to 5.83 million tonnes, according to figures from the commission, known as Cochilco.
(Reporting by Aislinn Laing; editing by Jonathan Oatis)