May 31, 2012 SANTIAGO (Dow Jones)--Copper output in Chile, the world's largest copper producer, rose 1.6% on the year in April to 445,378 metric tons, the government statistics agency said Thursday.

The National Statistics Institute, or INE, attributed the gain to increased production at mines that came on line in 2011.

For the January-April period, Chile produced 1,731,677 tons of copper, an increase of 1.3% on the year.

Last year, Chile produced 5.25 million tons of the industrial metal, which represented a decrease of 3.2% from what it mined in 2010.

As well as mining roughly a third of the world's copper, Chile also is one of the leading producers of molybdenum, iodine, lithium, gold and silver. The mining industry represents about 15% of the country's gross domestic product, according to the central bank.

Molybdenum output in March retreated 5% year-to-year to 2,928 tons, due to lower ore grades, the INE reported.

Molybdenum, which is used to harden steel, and precious metals such as silver and gold are often found as byproducts at Chilean copper mines.

In January-March, molybdenum output fell 17% on the year to 10,350 tons. Last year, production of the metal rose 10.7% to 40,994 tons.

Gold production rose 8% on the year while silver production fell 12%, the INE reported without providing output figures.