Hemlo 34% M&I resource lift: project economics and design notes for mine planners
Reviewed by Joe Ashwell
First reported on MINING.com
30 Second Briefing
Hemlo Mining has increased measured and indicated resources at its namesake Ontario operation by 34% to 96.9 million tonnes at 1.55 g/t gold, totalling 4.84 million oz., with inferred resources up 39% to 12.1 million tonnes at 2.22 g/t for 866,000 oz. The update, dated 31 December, incorporates drilling from a 130,000-metre programme, revised geological models and a higher long-term gold price assumption of US$2,500/oz, and includes a new A-Zone lens (635,000 inferred tonnes at 3.43 g/t). Underground M&I resources rose 40% to 24.9 million tonnes at 3.53 g/t (2.83 million oz.), while open-pit resources increased to 2.01 million oz., feeding into a new technical report due in H2 2027.
Technical Brief
- Long-term planning now assumes US$2,500/oz gold, up from US$1,900/oz in 2025 models.
- The current estimate supersedes a 2025 technical report, adding ~1.2 million contained ounces.
- Hemlo’s 130,000 m drilling campaign targets both conversion and new lenses; ~45,000 m completed in 2026.
- Near-mine targets under active drilling include E‑Zone, Horizon Zone, B‑Zone Deep, South Rim and A‑Zone.
- Newly defined A‑Zone remains open in all directions, indicating potential for further step-out resource additions.
- Upcoming H2 2027 technical report will integrate open-pit optimisation and revised underground mine plans.
- Hemlo complex has produced ~25 million oz since 1985 from Williams, David Bell and Golden Giant operations.
Our Take
The resource gains at the Hemlo mine tie directly to the aggressive drilling our database has tracked at South Rim and the new E‑Zone at Williams, where recent intercepts such as 16.1 g/t over 8.1 m signal that higher‑grade shoots are still being defined within this mature Ontario gold camp.
With Hemlo Mining now valued around C$1.7 billion on the back of a 34% uplift in measured and indicated gold resources, the asset is moving into the tier where, in our coverage, mid‑tier and major producers often reassess M&A options for long‑life Canadian gold operations.
The stronger inferred grade at depth (including 3.43 g/t in the A‑Zone) compared with the broader resource base suggests that further underground conversion drilling could both extend mine life beyond the second half of 2027 planning horizon and support higher‑margin underground sequencing at Williams.
Prepared by collating external sources, AI-assisted tools, and Geomechanics.io’s proprietary mining database, then reviewed for technical accuracy & edited by our geotechnical team.
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