TORONTO - Brazilian miner Vale said it has closed a furnace at its Copper Cliff nickel smelter in Sudbury, Ont., for at least 16 weeks, due to an undisclosed problem.

The stoppage is expected to reduce output of finished nickel at the Northern Ontario facility by 15,000 tonnes, or five per cent of the total planned output in 2011.

No other details were immediately available.

Nickel is used to produce stainless steel and special alloys. It is also an ingredient used in electronics, construction materials and medical equipment.

Vale is the second-largest mining group in the world. It bought Inco in 2006.

It has more than 12,000 employees working with nickel in Canada, the United States, Indonesia, Asia, New Caledonia, the United Kingdom and Brazil.