Sulphurets has potential to rial anything in B.C.

Exploration and mine development in northern British Columbia is risky business — even when you know what you’re doing. So joint venture partners Newhawk Gold Mines (TSE) and Granduc Mines (TSE) have adopted a very conservative approach to evaluating their Sulphurets gold project 50 miles north of Stewart.

With geologic reserves of 1.5 million tons grading 0.51 oz gold and 20.2 oz silver in the West zone, the discovery represents one of the largest untapped gold reserves in Western Canada — on a par with the Cominco/Delaware SNIP project to the west.

Silver, an economic factor in a feasibility study, will have to be shipped out in concentrate form by road (a portion of which traverses a glacier) which isn’t a problem, according to Newhawk President Don McLeod who has a wealth of experience in northern climates. He predicted barge access (via Bowser Lake) and a roadway to the mine site should be completed by the end of August. This will connect the property to Highway 37 and Stewart which is on a tidewater. Good access to the property is critical, both during mine development and operational phases. Servicing a property by air is expensive and it features prominently in the feasibility study of any new mine.

The joint venture recently completed a $3.4-million exploration program at Sulphurets, most of which was concentrated on the West zone. The program included underground work on the 1350-ft and 1300-ft levels, raising on ore grade mineralization, deep surface diamond drilling, and road construction.

Fred G. Hewett, vice-president and exploration manager for Newhawk, said the underground development was “designed to define the geological picture necessary for mining reserve estimates.”

There appears to be considerable potential at depth. Two 1,900- ft-long surface holes intersected the West zone structure at depth but they deviated, flattened somewhat, and assay results are still pending. In any event, there were indications of quartz veining and silicification in the widely-spaced holes.

A $5.2-million exploration budget has been approved for the 4-month period ending Oct 31, 1988. The southern portion of the West zone will be accessed from existing underground workings for drilling purposes, and the decline will be advanced to the 1250-ft level or about 650 ft from surface.

McLeod said the upcoming program will be funded by flow-through and its major shareholder (41%) Corona Corp. will take down part of the offering. Corona has the right to maintain its present equity position in any future issue, he added. But he declined to speculate on the possibility (“I can’t answer that”) of a Corona/Newhawk merger in the future.

With the help of Corona, Newhawk expects to begin an in-house feasibility shortly which would be independently reviewed at a later date. This study will establish a mineable reserve and optimum production rate. McLeod said the company’s Stage 1 report is about 70% completed and he doesn’t see much of a problem “because of the isolation.” The study will probably be submitted within the next 60 days, he said.

Exploration work is also planned on several surface targets including the Shore and Gossan Hills zones which have good potential but are relatively unexplored. An attempt will be made to extend the Shore zone (539,776 tons at 0.26 gold and 27 oz silver) away from Brucejack Lake and drilling is planned for the zone this summer. Several showings will be trenched. The whole region is well mineralized and bulk tonnage potential exists in the Snowfield zone about six miles away. Tom Drown, senior geologist for the project, estimated that potential at 10 million tons grading 0.08 oz gold.

Drown told The Northern Miner that the West zone has a strike length of about 2,000 ft of which approximately 1,650 ft had been explored. It’s still open to the south and has not been cut off by faulting, he noted. The bulk of the reserves occur in oblique-trending veins or tensional fractures that were in-filled with quartz.

These oblique veins cut the main north-south regional trend (where quartz veining also occurs) at about 35 degrees and typically have limited strike length, change dip and strike consistently, and are often difficult to follow, The Northern Miner gathers. (This seems to be the rule, rather than the exception in these vein type deposits). Ground conditions are generally good although there are a few open fault zones.

At least 15 zones are known to exist and there are 10,000 sample points in the West zone alone which has an average thickness of seven feet and a cut off grade of 0.15 oz gold. The gold is mostly in electrum, a naturally- occurring gold-silver alloy and metallurgical test work indicates about 65% of it will come out through gravity separation. Ore shoots tend to be about 150 ft long and about three times that distance on the dip angle. A high grade ore shoot on the 1,300 foot level (in the middle of the West zone), averaged six feet in width and returned values up to 8.0 oz gold and 600 oz silver. It extends down dip about 230 ft down dip and probably connects up with a high grade zone above, said Drown, who noted it sometimes only takes one good ore shoot like this to ensure payback.