Nuinsco sees widely disseminated sulphides at Lac Rocher

The release of new drill results from the Lac Rocher property in northwestern Quebec seems to have disappointed the market less this time around. Shares in property holder Nuinsco Resources (NWI-T) were off only slightly as the explorer announced it had drilled 26 more holes and intersected mostly disseminated sulphide mineralization.

Nuinsco, which became a market darling early in the year when it released assays from the discovery hole on the project, was beaten up by the market when it announced results in March. The early-stage exploration project, while it continues to show results that company management describes as “encouraging,” has not fulfilled the inflated hopes the market had placed on it.

In the newest drilling, the most strongly mineralized intersection was in hole 11, drilled vertically near the discovery area. The hole cut a 48.3-metre interval grading an average of 0.65% nickel and 0.27% copper. The pyroxenite host rock contained up to 15% sulphides, which were disseminated rather than massive.

Holes 10, 12 and 15, all of which were drilled immediately southeast of the discovery area, intersected disseminated sulphides in gabbro and pyroxenite, with nickel values generally between 0.05% and 0.5%. A fourth hole was abandoned at 34 metres in faulted rock.

Several holes tested areas farther south and east of the discovery area. These, generally collared 100 to 200 metres away from the discovery holes, intersected gabbro and pyroxenite with disseminated sulphides. Samples yielded similar nickel values to those from the other holes (0.05-0.5%).

Four holes collared 600-800 metres southeast of the discovery area all intersected disseminated sulphides in gabbro and pyroxenite, or pyroxenite only. Hole 30, drilled about 1 km southeast of the main mineralized intersections, encountered only the paragneiss country rock outside the gabbro intrusion. Samples from another six holes, drilled southwest of the intrusion to intersect it at depth, are out for assay.

Nuinsco’s exploration strategy has two prongs: the company is trying to trace the extension of the known massive sulphide mineralization to a deep central feeder zone, presumably southeast of the discovery area, and, at the same time, is testing other areas on the property where geophysical evidence suggests there may be other gabbro bodies that could be mineralized.

The massive sulphide body appears to be faulted, and its extension has yet to be found. Nuinsco is using down-hole geophysics as a guide, and Douglas Hume, the company’s president, thinks the massive sulphides found so far may be part of an upward-faulted block, indicating that the extension may be deeper than the discovery zone. “Things have certainly been disrupted by faulting, and it’s going to take some time and effort to sort it out,” says Hume.

To assess other parts of the property, Nuinsco has cut grids at the locations of three magnetic anomalies found in earlier airborne geophysical surveys, and has performed some ground magnetic and electromagnetic surveys to spot likely drill targets. Another diamond drill has been moved on to the property to test these anomalies.

An airborne electromagnetic survey is also under way, to cover the entire land package. With the addition of a claim block of 38 sq. km adjacent to its property, Nuinsco now has about 70 sq. km. The new ground, purchased for $60,000 cash and 100,000 shares from the prospecting syndicate that vended Nuinsco’s original claims, was subject to an application process because Hydro-Quebec holds flooding rights over part of the area.

The mines division of the Quebec Ministry of Natural Resources was quick to publish a report on the Lac Rocher area. Written by geologists Daniel Bandyayera and Remy Morin, the report (numbered PRO 99-06 and titled The Rocher Lake showing and the nickel-copper potential of the Frotet-Evans area) concludes that a number of similar mafic-to-ultramafic intrusions exist in and around the Frotet-Evans greenstone belt.

Bandyayera and Morin consider the Lac Rocher gabbro to be one of the late tectonic plutons and dykes that intrude the greenstones and the enclosing gneisses. They suggest that geochemical evidence points to late, rather than early, accumulations of sulphides in these rocks, which favours the development of massive sulphide bodies near the base of the intrusion.