U.S. MINERALS <USMX.O> COMMISSIONS NEW GOLD MINE U.S. Minerals Exploration Co said it and Pegasus Gold Inc <PGUL.O> of Spokane, Wash, officially commissioned a new gold, zinc and lead producing mine. U.S. Minerals said the new Montana Tunnels Mine near Helena, Mont, is expected to reach full production in August 1987. U.S. Minerals said the mine is designed to operate at an average of 12,500 tons or ore per day and is projected to produce 95,000 ounces of gold in 1988, plus significant quantities of silver, lead and zinc. U.S. Minerals said it has a 50 pct net profit royalty interest in the mine after payback of development costs.