The O’Brien mine, halfway between the towns of Rouyn-Noranda and Val-d’Or along the Larder-Lake-Cadillac fault, was considered the highest grade gold producer in Quebec between 1926 and 1957, when the underground operation churned out 1.20 million tonnes grading 15.25 grams gold per tonne for 587,121 oz. gold.
Today, the historic mine is part of Radisson Mining Resources (TSXV: RDS; US-OTC: RMRDF) O’Brien project, where the junior exploration company has carved out a resource estimate that begins 600 metres to the east and along strike of the mine’s Shaft No. 2.
Completed in March 2018, and using a cut-off grade of 3.5 grams gold, Radisson’s O’Brien deposit contains 1.13 million indicated tonnes averaging 6.45 grams gold for 233,491 contained oz. gold and another 1.16 million inferred tonnes grading 5.22 grams gold for 194,084 oz. gold.
The O’Brien deposit remains open at depth …
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