Stornoway Diamond Corp. is forecasting a start to ore processing at its Renard diamond project in the James Bay region of north-central Quebec by the end of September, with the project reaching commercial production by yearend. The Renard mine will be the first diamond mine in Quebec and will be the only diamond mine in Canada to be accessed by an all-season road.
Renard’s average diamond production in years 1 to 10 is forecast at 1.8 million carats/year, with 1.9 million carats to be produced and 1.4 million carats sold through the end of 2017. Initial plant throughput is planned at 6,000 mt/d, increasing to 7,000 mt/d starting in 2018.
Preproduction capital cost to develop the Renard project is estimated at C$775 million within a life-of-mine capital cost estimate of C$1.05 billion. Life-of-mine average operating costs are estimated at C$56.20/mt, or $84.37/carat. Life-of-mine net revenue is forecast at C$4.56 billion, yielding a real-terms cash operating margin of C$2.68 billion.
Renard project mineral reserves currently stand at 22.3 million carats contained in 33.4 million mt for an average grade of 67 carats/100 mt. Mine life based on these reserves is forecast at 14 years.
Renard mining operations began in 2015 in an open pit on the Renard 2 and Renard 3 kimberlite pipes, and ongoing open-pit production will provide the bulk of plant feed until 2018. The pit will be mined to a depth of 130 m at a stripping ratio of 2.54:1.
Underground ore will be sourced exclusively from the Renard 2 kimberlite between 2018 and 2027 and from the Renard 3 and Renard 4 kimberlites between 2027 and 2029. A blast-hole shrink stoping method with panel retreat will be used at Renard 2, based on production levels at 290, 470, 590, and 710 m depth. Long-hole stoping will be utilized at Renard 3, with one production level at 250 m depth based on the current limit of indicated mineral resources. Blasthole stoping beneath a crown pillar will be employed at Renard 4.
Stornoway President and CEO Matt Manson said, “The Renard project continues to demonstrate a robust valuation and a cash operating margin of 59% after all taxes, royalties, and the Renard diamond stream, despite the substantial recent reduction in rough diamond prices. We look forward to building on our track record to date of solid project execution as we bring Renard into production later this year.”