Gibralter issue should raise about $5.8m.

Gibraltar Mines has approved the filing of a preliminary prospectus for a common share issue which should raise about $5.8 million. Some 554,546 shares will be sold at a price of $8.25 each by the company’s fiscal agent, Dominion Securities Inc.

Gibraltar owns and operates an open pit copper mine near Williams Lake, B.C., which produces copper concentrate, cathode copper and molybdenum as a by- product. Mineable reserves as of Sept 30, 1986, were 103.7 million tons grading 0.32% copper and 0.0094% molybdenum at a strip ratio of 0.84 to one.

Reserves of Cuisson Lake Mines (in which the company holds a 40.5% interest) covering part of the Granite Lake zone are estimated to be 6.9 million tons averaging 0.37% copper and 0.009% molybdenum. But these are not included in that reserve inventory.

There are approximately 91 million tons in waste dumps grading 0.145% copper which are being leached to recover cathode copper, a first in Canada. The low-cost biological leaching process has been employed at mining operations in the southwestern U.S. but not under Canadian climatic conditions. The $17-million solvent extraction and electrowinning plant is expected to recover 10 million lb of copper per year. It now is in operation.