HECLA <HL> TO BUY MINE STAKE FROM BP <BP> UNIT Hecla Mining Co said it has agreed to purchase a 28 pct interest in the Greens Creek Joint Venture from British Petroleum Co PLC's Amselco Minerals Inc unit. The venture expects to bring into production a gold-silver-lead-zinc ore body on Admiralty Island, Alaska, containing about 3,500,000 short tons of ore assaying about 0.18 ounce of gold, 24.0 ounces of silver, 9.7 pct zinc and 3.9 pct zinc per short ton, Hecla said. It said there is significant potential for the discovery of additional ore. Hecla said initial production from a trackless underground mine is scheduled for late 1988 at a rate of about 1,000 tons or ore per day. "At this rate, the Greens Creek mine will be the largest domestic silver mine and is expected to be one of the lowest cost producers." The company said it estimates its total investment in the project, including its share of preproduction costs, at about 45 mln dlrs, to be funded through internally generated cash and existing lines of credit. It said Amselco will retain a majority interest in the project. Other interest holders are CSX Corp <CSX> and <Exaias Resources Corp>.