The 2,000 members voted on a contract that maintains the pension plan for all employees and provides pay parity for workers at the company's smaller, nearby Fire Lake mine, the union said.

Last week, the union gave a 72-hour strike notice after rejecting the company's offer over concerns about wages, pensions, sub-contracting and pay disparity.

Union workers operate the large open pit Mont-Wright mine in Quebec, a railroad link to port, a processing plant in Port Cartier and Fire Lake mine.

Last year, Mont-Wright produced some 27 million tonnes of iron ore at a cash production cost of $25 per tonne.

In 2013, ArcelorMittal sold a 15 percent stake in Mont-Wright to South Korean steelmaker Posco and Taiwan-listed China Steel Corp for $1.1 billion.

(Reporting by Susan Taylor; Editing by Leslie Adler)

Stocks treated in this article : ArcelorMittal, China Steel Corporation, POSCO