Porphyry copper-gold deposit discovered in Sulphurets camp

A large tonnage, near surface, metamorphosed porphyry copper-gold deposit has been defined by trenching, geophysical surveys and diamond drilling on the Kerr property located 60 km north of Stewart, B.C. While 20 years ago even the hint of a discovery of this nature would be cause for jubilation, the economics of the day call for prudence as far tougher criteria must be met to determine viability.

The project is a joint venture in which Western Canadian Mining (VSE) is operator and owns a 70% interest. (Western Canadian Mining is held 40.5% by Consolidated Brinco and 28.1% by Cassiar Mining.) Sulphurets Gold (VSE) owns a 25% interest in the Kerr property which is located in the Sulphurets camp adjacent to the Newhawk/ Granduc gold-silver property. Accessibility and logistics are far from ideal, and will likely require some problem-solving before a mining operation could be put into place.

According to Bob Hewton, Western Canadian’s exploration manager, the property has been worked slightly since 1984. “But we only became aware of the copper-gold mineralization last year when in the process of looking for gold mineralization two of our holes intersected very extensive copper.” Results were 265 ft of 0.61% copper and 0.009 oz gold, and 284 ft of 1.10% copper and 0.011 oz gold per ton.

The 1988 exploration program was completed in early September and included a total of 11,774 ft of drilling in 22 holes, as well as geological, geophysical and geochemical surveys. Work was concentrated on two targets, the copper-gold mineralization and some high grade gold-silver mineralization on the west side of the property.

The company said geophysical surveying on the copper-gold target defined an area of low resistivity and high chargeability over a length of 6,561 ft that is still open in both directions. Diamond drilling tested 3,280 ft of the geophysical anomaly and outlined a porphyry copper-gold system, with a high grade copper-gold core that averages 328 ft in thickness and has been intersected up to 656 ft downdip. The company reports that a large number of drill holes returned intersections equal to or in excess of 1% copper and 0.010 to 0.015 oz gold per ton.

Results from 1988 drilling include 401 ft of 1.27% copper and 0.011 oz gold; 469 ft of 1.0% copper and 0.012 oz gold; and 167 ft of 1.12% copper and 0.016 oz gold per ton. (A number of 1988 drill holes ended in mineralization.)

The company describes the copper mineralization as relatively fine- grained, consisting of primary chalcocite, chalcopyrite and some native copper. Based on 12 drill holes and geological correlation, the company has defined a deposit that averages 0.84% copper, 0.01 oz gold and 0.06 oz silver per ton with current indicated dimensions of 3,280-ft strike length, 328-ft thickness and 656-ft width.

Although substantial in-fill drilling will be required to confirm the exact geometry of the deposit and the reserves, the company has inferred some 66.0 million tons using the above dimensions and a specific gravity of 3.0. The deposit dips 50 west and is open in three directions.

According to Victor Hollister, P.Eng., an independent consultant, the project has good potential for increasing both tonnage and grade. “Given the nature of the ore exposed in drilling to date, it should be anticipated that the best grade hypogene ore has yet to be intersected,” he said.

Hewton said that after all results from the 1988 program are compiled and evaluated, the company will undertake a preliminary economic appraisal of the project prior to planning a work program for 1989.