Northisle Announces Continued Growth of West Goodspeed Target to over 1.2km Strike with Additional High-Grade Intervals

The November 17, 2025, news release announces continued positive drill results from the West Goodspeed target at its North Island Project. The highlights include: - Mineralization has been extended to a strike length of over 1.2 kilometers and a vertical extent of 280 meters. - Hole RD25-07 returned a high-grade interval of 39 meters grading 1.16% Copper Equivalent (Cu Eq), within a broader interval of 93 meters grading 0.77% Cu Eq. - CEO Sam Lee stated that the company has now commenced work to incorporate the West Goodspeed target into the project's mineral inventory, which will be used to support a planned pre-feasibility study (PFS). - The release notes that Copper Equivalent calculations are based on assumed 80% recoveries, as metallurgical testing on West Goodspeed material has not yet been completed.

This news is materially positive and represents a successful and logical continuation of the company's exploration strategy. The key impact comes from placing these results in the context of developments over the past year:

1. Upside to an Already Robust PEA: The February 2025 Preliminary Economic Assessment (PEA) outlined a compelling project with a C$2.0 billion after-tax NPV and a 29% IRR. Crucially, the West Goodspeed target was not included in that study. Every successful drill hole at West Goodspeed adds potential tonnage and grade that could significantly enhance the project's economics in the upcoming PFS, potentially by providing higher-grade starter material.

2. Confirmation of Exploration Thesis: Following a transformative C$39.5 million financing in August 2025, Northisle quadrupled its planned drill program to over 27,000 meters. These positive results validate that aggressive spending, demonstrating that the geological model is working and the company is effectively deploying its large cash balance to de-risk and grow the project.

3. Grade and Scale: The headline intercept of 39 meters at 1.16% Cu Eq is a strong result for a porphyry system and builds on previous good intercepts announced in July and September 2025. Extending the strike length from 1.0 km (as per the September release) to 1.2 km is steady, incremental progress that builds confidence in the size of the mineralized system.

While the news is strong, it is not a "Game Changer" in the same way the August C$39.5 million financing was. That event secured the company's future through the PFS. This news confirms the company is executing its post-financing plans effectively.

The primary risk associated with this news is explicitly stated in the disclaimer: the Copper Equivalent calculation assumes 80% metallurgical recoveries. This is a critical assumption that requires confirmation through testing. If actual recoveries are materially lower, the economic contribution of this mineralization will be reduced.

Overall, the market should view this news positively as it de-risks the inclusion of West Goodspeed in the PFS and demonstrates consistent exploration success.

Northisle Copper and Gold Inc. is a Canadian mineral exploration and development company focused on its 100%-owned North Island Project, located on Vancouver Island, British Columbia. The project is situated in a Tier-1 mining jurisdiction and covers a 35-kilometre-long porphyry belt. Its primary assets are several copper-gold porphyry deposits, including Hushamu, Red Dog, and Northwest Expo. The company's strategy is to advance this district-scale project towards production, building on a robust February 2025 PEA which outlined a large-scale, long-life, and low-cost potential mining operation. The current exploration focus is on defining and expanding the recently discovered West Goodspeed target for inclusion in a future Pre-Feasibility Study.