Exploration and development company Osisko Metals has announced an updated mineral resource estimate (MRE) for the Gaspé copper project, near Murdochville, in Quebec.

The updated estimate includes pit-constrained resources comprising 824-million tonnes grading 0.34% copper-equivalent of indicated category and 670-million tonnes grading 0.38% copper-equivalent of inferred category.

This represents a 53% increase in copper-equivalent metal content over the previously reported indicated resource and a 100-fold increase in copper-equivalent metal content in inferred resources.

Osisko states that, at 4.91-billion pounds (2.23-million tonnes) of contained copper, as well as significant molybdenum (274-million pounds) and silver (46.0-million ounces), the latest Gaspé copper in-pit indicated resource hosts the largest undeveloped copper/molybdenum deposit in eastern North America, exclusive of inferred resources.

“The overall resource has increased dramatically since last spring’s MRE as a result of new geological modelling and extending the modelled Whittle pit boundaries towards Needle Mountain to the south,” says CEO and chairperson Robert Wares.

A minimum 70 000 m drill programme is now planned for 2025, with the objective of converting the bulk of the current inferred resource to the indicated category.

There is also potential for converting currently categorised in-pit waste rock to mineralised material with this drill programme, which would further grow the in-pit resource while reducing the strip ratio.

“This MRE represents a much larger resource than was estimated previously, presenting the potential for a bulk tonnage mining operation with significantly higher throughput,” says Wares.

Given the new resource milestone, Osisko has elected to defer the preliminary economic assessment (PEA), originally slated for release in the first quarter of 2025, to a later date, until additional new drilling is completed.

Ongoing studies will focus on a larger-scale mine plan and relocation of the mill complex away from the current site.

“We are proud to be leading the Gaspé copper project, which is shaping up to be a major Canadian copper/molybdenum development project located in one of the world’s safest mining jurisdictions. This important asset has the potential to become a core component of Québec’s critical mineral development strategy that aims to provide essential metals for global decarbonisation initiatives,” says Wares.