Cargo ships transport nickel concentrate from the Voisey's Bay mine in northern Labrador. (CBC)

Brazilian mining giant Vale says it will continue to use replacement workers at its Voisey's Bay nickel mine in northern Labrador.

More than 50 maintenance workers, employed by Ushitou Maintenance, a contractor working for Vale at the mine site, walked off the job there this week.

They joined 200 Vale workers in Labrador who've been on strike since August.

Vale — known as Vale Inco until recently — brought in replacement workers in February to increase production at the nickel mine.

A company spokesperson said Thursday that the contractor Vale is using will do the same with maintenance work.

"We recognize that unionized employees certainly have the right to exercise their rights to strike but we as a company also have the right to operate our business and to continue to operate our business and to continue to meet the needs of our customers," said Vale's Bob Carter. "We'll continue to provide employment to people who are not on strike."

The maintenance workers and the miners are both represented by the Steelworkers Union, but they are in different bargaining units.

A Vale official said last week that the company was able to make only one shipment of Voisey's Bay nickel concentrate from Labrador this winter.

About 3,000 workers at Vale's Sudbury, Ont., mine have been on strike since last July.