Chile's copper output increased in December 2009 thanks to higher copper in concentrate production, the national statistics bureau INE said.
This was despite the country's overall industrial output declining.
In December 2009 copper output increased to 501,950t, representing a 3.8% rise compared to December 2008.
Chile's copper in concentrate output in December 2009 rose by 14.5% to 231,202t compared to the same period in the previous year.
Cathode output, however, declined by 7.2% over the same period due to labour unrest.
Chile's copper output for the whole of 2009 increased by 0.8% to 5.41 million tonnes compared to 2008.
Production of gold, silver and iron ore also increased in December, while molybdenum production declined.
The company's total mining output in December increased by 1.7%, while full year production increased by 0.1%.