Val d’Or, Que. —
Results from the last four holes are highlighted by one in the Upper Halet zone, which cut 13.5 metres grading 8.75 grams gold per tonne (all widths are true widths).
Ten gold zones have been outlined. The Upper Halet has a strike length of at least 210 metres and is open in both directions along strike. Earlier this year, a hole in this zone cut 17.2 metres grading 6.2 grams gold, including 5.9 metres grading 11.6 grams gold per tonne.
Another hole hit the Chet zone at 97 metres down-hole and returned 5.2 metres grading 5.2 grams gold per tonne; at 50 metres farther down-hole, the hole cut another zone, which graded 6.7 grams gold over 3 metres.
In the latest drilling, two holes deviated from their proposed targets; one failed to intersect significant mineralization, whereas the other hit 1.4 metres that graded 5.6 grams gold.
The property hosts the past-producing Malartic Goldfields mine, which included 23 gabbroic and mafic lenses similar to the zones being drilled. More than 2 million oz. gold were produced from 1939 to 1960. The mill grade was 8.6 grams gold per tonne, and 9 million tonnes of ore were processed.
The headframes and townsite are long gone, but two 800-metre-deep shafts, about 800 metres apart, and a sample assay facility remain.
Northern Star’s drilling has focused on an area between the two shafts. The company intends to de-water the 3-compartment shaft and explore the property from underground.
Northern Star recently entered into a purchase agreement with
Northern Star plans to move the infrastructure a distance of about 35 km and reassemble it at the site. The company has a mining engineer on staff; however, a consulting firm has been given the contract to help design and install the headframe foundation.
The first level of the old mine is at 400 ft., and Northern Star plans to begin underground drilling into the Halet zone from this level. If all goes as planned, the mine will be dewatered to 900 ft.
“We are worried about drilling from surface because of the deviation,” Michel David, Northern Star’s president, explains. “As a junior, we can’t afford to miss our target. If I announce fifty holes and I have thirty-nine with mineralization, and I have one or two that have nothing, the market is going to respond in a negative way. We have to look at that.
“We have looked at the cost. We have watched what Agnico has spent at Lapa on surface and what they are still going to spend (underground), and we have decided to jump-start that. It will be cheaper in the long run than drilling from surface.”
The company believes rehabilitating the shaft will be straightforward. Northern Star has placed a new secure cover over the 2-compartment shaft, and the area around the shaft has been cleared in preparation for the equipment.
Dewatering will take a few months, so underground drilling probably won’t begin before next fall. In the meantime, surface drilling continues.
Four or five zones are reasonably well-defined. Halet has been cut 120 metres down; it is 185 metres long and about 6 metres wide. “We don’t really have to worry about defining it,” David states. “We will just try to extend it. We want to go get it. We would like to get to the other dimension.”
Earlier drilling by Northern Star into the Halet zone was highlighted by a 17-metre intercept of 9.2 grams gold per tonne. Within this interval are 8.3 metres grading 15 grams gold beginning at 117 metres down-hole.
Zones are locally stacked and vary in size from 90,000-360,000 tonnes. Northern Star’s drilling has identified zones with an average width of 8.5 metres and a grade of 9.6 grams gold per tonne.
Gold is primarily associated with, and directly proportional to, pyrite. Historically, miners would just follow the pyrite to follow the ore. Gold is within the pyrite but not locked in. Gold recovery from Malartic Goldfields’ ore was 97% using flotation.
Gold zones are found in ovoid-shaped gabbroic and mafic lenses in ultramafic rock. The theory is that the iron comes from the ultramafics and acts as a precipitate for the gold. Porphyry-type intrusions appear to be a factor in gold enrichment. Locally porphyry intrusions contain lower-grade gold. There is a halo effect near the porphyries. If there is anomalous gold in the porphyry, then the company has found that the adjacent gabbro should contain gold.
Looking at the geophysical maps, the porphyries have a subtle magnetic low signature, compared with the ultramafic rock. The dykes are not wide.
There was no road access when exploration began in the early 1930s. With negligible outcrop and little data, drilling began at 500-ft.-centres, and gold-enriched lenses were cut that formed the basis of a mine. In 1934, a 2-compartment-shaft was sunk, then a second one. In the late 1930s, the mining town of Halet was built at the site.
A Lac-Malartic Goldfields report from 1959 recommended drilling east of shaft 1 and below the town of Halet. It was never done and the mine was shut down.
Malartic Goldfields made as much money milling ore on a contract basis as it did from mining. The mill operated from 1938 to 1996 (treating Bousquet 2 ore in its latter years) and was dismantled in 1997.
Northern Star has managed to acquire historic drill hole data, longitudinal sections and level plans. The 1200 level connects both shafts; however, only four holes were drilled into the area between the shafts where the Midway zone is situated (partly because the town of Halet was there). One hole hit a portion of the Midway, but another couple of holes on either side of this missed it because they were not drilled in the right direction.
Midway was mined below 460 metres but not above. Northern Star has cut the Midway zone at a down-hole depth of 200 metres; a 24-metre interval of core graded 8.2 grams gold. Within this interval, one intercept graded 15 grams gold per tonne over 8.3 metres.
Drilling has targeted porphyries because mineralization appears to be restricted to corridors that follow their path. The mineralized zones appear to be stacked en echelon, and the company hopes to find more gold zones at depth.
Northern Star’s, vice-president of exploration, Eugne Gauthier, sums up Northern Star’s work, saying: “Historically, the discovery of deposits follows advances in technology. We are looking at the same property from another angle and it is working for us.”
Northern Star recently acquired the adjacent Malartic Goldfields property from
Northern Star has assumed any rehabilitation liabilities attached to the property (liabilities it considers negligible) and will deliver to Barrick a “certificate of liberation” from the Quebec Ministry of Natural Resources in this respect.
Water has been tested around the tailings, and, apart from one spot that has too much iron, the water is pure, according to the standards of the Ministry of Natural Resources. There are three dewatering ponds, which Northern Star will use.
The property acquired from Barrick has two surface leases for tailings. The tailings area has been re-vegetated and resembles a field. Northern Star will have to maintain the area by making sure sizable trees do not grow on it.
The 12-sq.-km Midway-Malartic property comprises 53 contiguous claims, two mining concessions, and two surface leases. The property is just 1 km south of the Trans Canada Highway and connected to it by a dirt road.
Northern Star has five gold projects in the Abitibi but is concentrating on Midway-Malartic. The company has 27 million shares outstanding (31 million fully diluted). In the past six months it has traded in the range of 45-75. At presstime, shares were trading at 50.
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