STOCKHOLM, Feb 5 (Reuters) – Swedish mining and smelting group Boliden said on Monday it had appointed the head of its Mines division Mikael Staffas as new chief executive at the group from June 1. Staffas replaces long-standing Boliden CEO Lennart Evrell who said late last year that he would be stepping down in mid-2018. With a background as a partner at McKinsey & Co, Staffas has worked at Boliden since 2011, first as chief financial officer and later in his current position as head of business area Mines, the smaller of the group’s two divisions by sales. However, the Mines division reported a 77 percent jump in operating earnings in the third quarter, easily eclipsing profits recorded for the bigger Smelters unit.