TORONTO, ONTARIO – (May 25, 2018) – McEwen Mining Inc. (NYSE: MUX) (TSX: MUX) (“McEwen Mining” or the “Company”) is pleased to announce results of a new Preliminary Economic Assessment (PEA) study evaluating the potential extension of production from its 100% owned El Gallo Complex in Sinaloa, Mexico. The proposed
redevelopment plan evaluated in the PEA is called Project Fenix. The key outcomes of Project Fenix include an average annual production rate of 47,000 ounces gold equivalent (AuEq), low initial capital cost, mine pay-back of 4 years, and an after-tax IRR of 25% at current gold and silver prices.