Nickel Rim South takes shape

A new massive sulphide deposit is quickly taking shape in the venerable Sudbury mining camp of northern Ontario.

Falconbridge (FL-T), one of the region’s two major producers, has now sunk eight holes in the Nickel Rim South zone. The zone lies 2.7 km north of the city’s airport and 2 km northwest of the company’s Rim deposit, where inferred resources stand at 1.6 million tonnes grading 1.6% nickel, 10.1% copper, 4.2 grams platinum, 3.5 grams palladium and 2.5 grams gold per tonne.

Mineralization is typical of the basin, being associated with the complex’s contact layer and the underlying brecciated granodiorite and Sudbury breccia. So far, grades appear to be higher in the footwall rocks.

Results are available for seven of the holes drilled, five of which are wedges off the first hole drilled. Hole 100 did not cut the zone proper but rather alerted Falconbridge to the area’s true potential when it averaged 1.89% copper plus 0.71% nickel over 0.1 metre (starting at 1,443 metres down-hole) and 0.26% nickel plus 20.30% copper over 0.3 metre (at 1,561 metres).

Within the contact layer, pilot hole 102 cut the thickest section of mineralization; that is, 68.8 metres (at 1,235.4 metres) averaging 1.99% nickel, 1.41% copper, 0.73 gram platinum, 0.51 gram palladium and 0.3 gram gold. The intercept begins 204 metres east of hole 100A, which was the first wedge off hole 100 and which averaged 2.86% nickel, 1.91% copper, 0.84 gram platinum, 0.67 gram palladium and 0.24 gram gold over 4.3 metres (at 1,440 metres).

Wedge-hole 100E yielded the highest average nickel grade of 2.10% over 18.5 metres (at 1,418 metres) of contact rock. The interval is 36 metres east of the one cut by hole 100A and also carried 0.51% copper, 0.81 gram platinum, 0.63 gram palladium and 0.08 gram gold.

Nickel and copper grades for wedge-holes 100B-D varied from 1.5%-2.86% and 0.51%-1.91%, respectively. Platinum, palladium and gold each averaged less than a gram over the section reported.

In the footwall layers, wedge-holes 100B, 100C and 100E pierced between 46.8 and 49.4 metres of mineralization. Nickel values varied from 2.82% to 4.55%; copper, from 3.53% to 13.63%; platinum, from 3.05 to 9.22 grams; palladium, from 3.26 to 11.94 grams; and gold, from 1.25 to 8.86 grams.

Results for wedge-hole 100D and 102 are similarly favorable and just as comparable to those of the rest. For reference, hole 100A cut the thickest section of mineralization –72.9 metres (at 1,575.9 metres) grading 1.76% nickel, 6.45% copper, 5.2 grams platinum, 6.53 grams palladium and 3.67 grams gold.

Results are pending for hole 103, though Falconbridge hints at its successful intersection of mineralization by noting core lengths. Hole 101 failed to intersect any mineralization.

Borehole geophysical surveys suggest that mineralization remains open up-plunge to the northeast and down-plunge to the southwest. Falconbridge has four drills testing the possibility.

Falconbridge notes that thicknesses for footwall mineralization are based on a cutoff grade that would be applicable to a bulk-mining scenario. For instance, hole 100B carried higher-grading subintervals as long as 18.9 metres in core-length at a grade of 8.5% nickel, 12.98% copper, 16.3 grams platinum, 17.07 grams palladium and 8.04 grams gold.

Drilling is expected to finish in June, after which a resource estimate will be carried out to determine the future scope of the project.