Junior
Having run up as high as $8.10 in December 2000 on the back of initial drill results from the first five holes on the Midrim prospect in Quebec, Aurora has settled into a $5-4.30 trading range. The junior remains a top pick of Brent Cook, an analyst with Global Resource Investments, based in Carlsbad, Calif.
Originally focused on PGM targets, Aurora was created by the management of
Daniel Innes, vice-president of exploration for Southwestern, had previously spent 16 years as a district geologist with the Ontario Geological Survey in Sudbury, Ont. He used his extensive knowledge of the area to assemble a package of prospective properties and targets in Ontario and Quebec.
Aurora’s first move was to enter into an option agreement with
Says Cook: “This deal is particularly significant because it involves the Sudbury Intrusive Complex, a mineralized system that represents the world’s largest depository of nickel-platinum metals. Free ground does not exist; the complex is controlled by either Falconbridge or Inco.”
This type of joint-venture agreement, in which a junior earns into a major’s property, is typically not in the best interest of the junior; in this case, however, it works for both. As is typical in mining camps, exploration is under the direction of the mine whose main objective is to replace depleting reserves, thereby extending the life of the operation. Exploration targets outside the mine area are often ignored or else receive only minimal work, says Cook.
Three recent discoveries by
– Totten — 10.1 million tonnes grading 1.5% nickel, 1.97% copper and 4.8 grams combined PGMs;
– Pump Lake — 3.5 million tonnes grading 1.4% nickel, 1% copper and 1.5 grams PGMs; and
– Copper Cliff — 300,000 tonnes grading 0.9% nickel, 4.5% copper and 16.4 grams PGMs.
South Footwall
The South Footwall project is 15 km northeast of Sudbury and includes 16 sq. km of patented and unpatented claims. The area is underlain by an 8-km strike length of Sudbury Igneous Complex (SIC) and sub-layer footwall rocks, which host the Falconbridge and Falconbridge East mines. A 3-km portion of this prospective unit is covered by overburden. The western boundary of the property is within 500 metres of Inco’s Garson mine.
Sulphide mineralization in the SIC occurs in basal units, offset dykes and embayments, and is almost always associated with norite.
According to Cook, South Footwall received only cursory grid-style drilling and limited geophysics in the past. Aurora completed a tightly spaced 50-metre airborne electromagnetic (EM) and magnetic survey that revealed significant conductors and deep geophysical targets. The Falconbridge East deposit shows up as a distinct anomaly at the SIC contact. Cook says the survey shows an almost identical anomaly offset slightly to the south on the joint-venture ground. The area covered by the anomaly has never been drilled.
In early March, Falconbridge, which operates the South Footwall project, began an initial, 4-hole program of deep drilling of 1,000 metres each on the main magnetic feature. The four holes will be surveyed using down-hole electromagnetics to determine if sulphide mineralization occurs at depth. In addition, a portion of the Footwall project has been covered by a ground EM survey. Results are pending.
The Foy project is part of a series of giant cracks that radiate outward from the Sudbury Basin. Some of the best mines in the district, especially those enriched with PGM-bearing copper sulphides, occur along these fractures. Situated 30 km northeast of Sudbury, the 19.5-sq. km Foy project covers a 10.5-km strike length of the Foy Offset dyke.
Outcrop is poor and the area has received relatively little exploration. Last summer, prospectors discovered a zone of disseminated to massive sulphide mineralization under thin cover in an area measuring 400 by 200 metres. The zone occurs at a bulge in the Foy Offset dyke. Cook, who visited the property last year while stripping of the overburden was in progress, observed at least four sulphide showings containing chalcopyrite, pentlandite and pyrrhotite, and ranging, in diameter, from a few metres to tens of metres. Norite and quartz-diorite clasts were present in the breccia. More than 150 continuous channel samples were submitted for analysis.
Aurora has drilled five vertical, 800-metre-deep holes for the purpose of carrying out EM surveys. The holes encountered variable disseminated to massive sulphide mineralization. The down-hole survey is a proven tool for locating offset-type deposits that commonly occur as finger-like or pipe-like bodies within the dyke.
‘Striking’ results
An airborne magnetic and EM survey was completed over a large portion of the property, the results of which, Cook says, are striking. “Seasoned geophysicists from both Aurora and Falconbridge believe they have located an embayment extending out from the SIC contact where the Foy Offset exits the SIC,” he writes. “Even more striking, the possible embayment hosts a known ore deposit held by Inco, which shows up as a distinct magnetic and/or conductive geophysical anomaly.” Five other nearly identical geophysical features occur within the proposed embayment.
These geophysical anomalies will be tested with about 8,000 metres of drilling.
Midrim
In December 2000, Aurora released encouraging results from the first five holes on the Midrim property, just across the border into Quebec, 20 km northeast of Ville-Marie. Values ran as high as 4.94% nickel, 4.74% copper and 0.11% cobalt, plus 1.24 grams platinum, 4.71 grams palladium and 0.17 gram gold per tonne, over 6 metres within a 38-metre intercept averaging 1.98% nickel, 2.07% copper, 0.07% cobalt, 0.48 gram platinum, 2.08 grams palladium and 0.13 gram gold. The holes covered a strike length of 110 metres.
The Midrim property, though drilled in the 1960s, was never systematically explored for platinum and palladium. The Main zone extends for a strike length of 230 metres, and the average of seven previous drill intercepts is 1.21% nickel and 1.67% copper over 13.6 metres.
The sulphide mineralization is hosted by a stacked suite of gabbro sills that have been tilted to about 60 and broken by faults. Based on the belief that hydrothermal processes are not responsible for the mineralization and that the sills themselves could not be the primary source of the high sulphide content, Aurora is looking for a much larger source.
A downhole EM survey was completed on all the Midrim holes, and deeper conductors were defined. An airborne magnetic and EM survey over the Midrim and adjacent Belleterre properties defined several interpreted anomalies at the Midrim, Lac Croche and Alotta prospects.
Aurora is using two rigs to define resources and test known prospects and significant EM conductors. A 10,000-metre program is planned over the course of the winter. Cook says an additional 30 holes have been completed.
Aurora can earn an initial 70% interest in the Midrim property by spending $1.2 million on exploration, paying $200,000 cash and issuing $200,000 worth of shares over three years. Once Aurora has vested, the owner either contributes, dilutes to a 2% net smelter return royalty, or elects to sell its interest, over which Aurora retains a right of first refusal.
Lansdowne House
Aurora’s fourth major project is the wholly owned Lansdowne House in Ontario, which covers the bulk of a mafic-ultramafic layered intrusive extending for some 20 km in strike length. Outcrop is generally poor, but limited rock sampling indicates that the complex is anomalous in PGMs. Drilling in the 1960s by Inco intersected both massive and disseminated nickel-copper-PGM mineralization over a large area. Aurora is targeting a large, low-grade system.
Recently completed airborne geophysics has identified a linear belt of anomalies at the base of the complex. Drilling is to begin shortly.
In a separate development, Aurora has entered into an agreement with Inco to interpret and process 30 years of airborne geophysical data over specific areas of Ontario. Aurora can earn the right to use and retain the data by spending $1.5 million over four years on follow-up work at geophysical targets. Inco retains a back-in right to an initial half-interest in any discovery, and will also have the right to buy any nickel-copper-PGM concentrates produced.
“The geophysical evidence for significant sulphide mineralization at all four properties is overwhelming,” says Cook. “Combined with the geologic setting, these are among the best exploration targets I have come across in 20 odd years.”
Last fall, Aurora completed a $6.6-million financing consisting of 2.4 million special warrants priced at $2.80 each. Aurora has 10.4 million shares outstanding, or 17.8 million on a fully diluted basis.
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