Osisko Gold Confirms High-Grade Proserpine System Near Cariboo

• Osisko Gold Group reported initial diamond drilling results from its Proserpine regional greenfield target in British Columbia, confirming a new mineralized system suitable for open-pit mining.
• The drill program completed 6,463 meters across 14 holes between February and May 2026, intersecting high-grade gold structures and broader lower-grade zones.
• Known mineralization at Proserpine has expanded to approximately one kilometer along strike by half a kilometer in width, with all holes reaching target depth encountering gold.
• Standout intercepts include hole PSP-26-004, which cut 4.6 meters grading 95.93 grams per tonne gold, including a 50-centimeter interval of 873 grams per tonne.
• National Bank Financial analyst Don DeMarco emphasized that the scale of the undefined target area is the critical takeaway, as mineralization remains open in all directions.
• Osisko has resumed drilling with three rigs to execute a further 26,500-meter program aimed at increasing density at Proserpine Southeast and exploring new zones.

How Do the Proserpine Drilling Results Compare to Historical Standards?

Osisko Gold Group Inc. has advanced its exploration efforts at the Proserpine target, located approximately seven kilometers southeast of the Cariboo Gold deposit in central British Columbia. The recent diamond drilling program, which concluded in May 2026, has successfully outlined a new mineralized system that complements the company’s primary development project. The results have validated the geological model, with all 14 drill holes that reached target depths intersecting mineralization from near-surface levels to depths beyond 400 meters.

The quality of the intercepts has drawn significant attention from market analysts and investors alike. Hole PSP-26-004 delivered exceptional grades, intersecting 4.6 meters grading 95.93 grams per tonne gold, which included a high-grade 50-centimeter interval grading 873 grams per tonne. Another notable intersection came from hole PSP-26-001, which cut 8.6 meters grading 5.46 grams gold. While these grades are exceptional, analysts note that the primary value driver is the scale of the target area rather than the grades alone.

The expansion of the known mineralized footprint to roughly one kilometer along strike by half a kilometer in width suggests a substantial resource base. The system remains open in all directions, indicating significant potential for further discovery. This open nature is critical for long-term resource growth, as it allows for the possibility of extending the mine life and increasing the total ounces available for extraction.

Why Is the Proserpine Discovery Significant for the Cariboo Project?

The discovery at Proserpine is strategically important for Osisko Gold because it supports the potential for open-pit mining operations alongside the planned underground operation at Cariboo. The Cariboo project itself features a permitted underground mine and processing complex, with a 2025 feasibility study envisioning a scalable operation producing about 1.89 million ounces of gold over a 10-year life.

The after-tax net present value of the Cariboo project is estimated at $943 million based on a US$2,400 per ounce gold price. The project currently holds 17.4 million measured and indicated tonnes grading 2.88 grams gold. The addition of a potential open-pit operation at Proserpine could significantly enhance the overall economics and lifespan of the Cariboo complex.

Analysts highlight that the scale of the Proserpine discovery is a key driver for the company's valuation. The ability to identify a sizeable new gold system close to existing permitted infrastructure reduces development risk and capital expenditure requirements. This synergy between the greenfield target and the permitted project provides a robust foundation for future growth.

What Is the Next Step in Osisko’s Exploration Strategy?

In response to the positive results, Osisko Gold has resumed drilling with three rigs to accelerate the exploration program. The company plans a further 26,500 meters of drilling to increase density at Proserpine Southeast and begin first-pass drilling at Proserpine Northwest. This expansion underscores the prospect of identifying a sizeable new gold system that could extend the mine life of the Cariboo project.

The exploration campaign is designed to test the potential of the larger target area that remains open in all directions. By increasing the drill density, Osisko aims to better define the geometry and grade of the mineralized system. This detailed understanding is essential for resource estimation and future feasibility studies.

Osisko Gold is a Canadian gold mining and exploration company listed on the NYSE and TSXV. Its primary focus is advancing its 100%-owned, permitted Cariboo Gold Project, targeting both high-grade underground-style mineralization and potential open-pit, bulk mining opportunities. While the stock currently holds a Neutral rating from TipRanks' AI Analyst Spark due to persistent losses and cash burn, the drilling success highlights the company's efforts to expand its resource base.

Recent deep drilling at Cariboo has also extended mineralization beyond 700 meters vertical depth, reinforcing long-term growth potential. The combination of high-grade underground resources and potential open-pit targets positions Osisko Gold for potential upside if gold prices remain favorable. The ongoing exploration program will be critical in determining the full extent of the Proserpine system.