Swedish mining and smelting company Boliden will invest Skr3.9bn ($590m) to expand its Garpenberg mine in Dalarna county, Sweden.
The investments will be used for developing a concentrator, new shafts, underground facilities and infrastructure of the mine.
Ore production is anticipated to grow from two million tons to 2.5 million by the end of 2015, with the facilities expected to become operational in 2014.
Boliden president Lennart Evrell said the expansion of the mine will cut unit costs and increase the possibility of utilising the area's geological potential.
Polymetallic ores containing zinc, silver, lead and smaller volumes of copper and gold are mined at Garpenberg.
The company plans to submit an application to the Environmental Court next month for a new environmental permit.