When the prevailing wisdom is that “anything worth finding near surface has already been found”, especially in the developed world, it is heartening to know that Canadian discoveries are still being made using old-fashioned prospecting.
Two new finds in particular come to mind: one a PGE deposit just an hour’s drive from the city of Thunder Bay in northern Ontario, the other a gold deposit in central Yukon where gold has been panned from streams for decades, but hardrock sources remained elusive.
In the first case, devoted field geologist Graham Wilson was investigating the boulder fields around Current Lake north of Thunder Bay in 2001 when he had the hunch to crack open one of the peridotite boulders. What he found inside was impressive PGE mineralization that warranted follow up.
Wilson contacted Australian Keith Watkins, his former graduate colleague at Cambridge University, who optioned the property through his junior company Magma Metals. Magma traced the boulder train up-ice back to its original source and started drilling.
Since then, Magma has outlined an indicated resource of 4.6 million tonnes grading 2.88 grams per tonne platinum equivalent (PtEq) and an inferred resource of 3.6 million tonnes grading 2.29 grams per tonne PtEq. The Thunder Bay North project is still growing.
The second example is Underworld Resources’ White Gold deposit in the Yukon. The day after president Adrian Fleming presented the find at the Prospector’s and Developers popular “New Discoveries and Developments” session in March, major gold miner Kinross Gold Corporation announced that it would pay a premium of 36% over the closing price of Underworld to get its hands on White Gold and its 1.5 million ounce gold resource.
Dawson City prospector Shawn Ryan, recently named British Columbia and Yukon prospector of the year for his work, started systematic soil sampling on the White Gold property in 2003. By the time Underworld optioned the claims in 2007, four thousand samples had uncovered six discrete gold anomalies at a threshold of 50 ppb Au.
Follow-up mapping, trenching, IP geophysics, and detailed soil samples confirmed previous work and returned grades of up to 1.8 g/t Au over 40m in channel samples. Subsequent drilling intersected the Golden Saddle and Arc deposits, both near-surface bulk tonnage zones potentially amenable to open-pit mining methods and open to expansion.
Both Magma and Underworld hail from Australia, where there is equal concern that all the “easy” deposits have been found. But as the Aussie juniors have demonstrated, it never hurts to take a second look on surface, even in someone else’s backyard.
“I’m completely blown away by the fact that all the creeks in the White Gold area have placer gold mining,” says Fleming. “But there has not been a single hole drilled for 50 kilometres in any direction.”