Northisle Launches Phase IV Exploration at North Island Project

• Drilling commenced 17 April 2025 with 789 metres completed as of 27 April from road-based pads
• 7,000-metre programme targets West Goodspeed resource definition and Northwest Expo intrusive identification in the Northwest Corridor
• West Goodspeed drilling includes seven infill holes and three step-out holes across 5,600 metres to test mineralisation extensions
• Field work encompasses surface mapping, soil sampling, stream sediment surveys, and geophysical analysis across the Northwest Corridor
• Integration of 60 years of property-wide exploration data underway to apply Northwest Corridor targeting methods across the 35-kilometre belt

Northisle Copper and Gold Inc. (TSX-V: NCX) is a Canadian mining company that owns the North Island Project through its wholly owned subsidiary North Island Mining Corp. The project comprises over 34,000 hectares of mineral titles located near Port Hardy, British Columbia, on a belt stretching 50 kilometres northwest from the former Island Copper Mine.

Northwest Corridor Drilling Programme at West Goodspeed and Northwest Expo

The 2025 drilling programme focuses on the Northwest Corridor, which includes the resources informing Phase 1 of the company's 2025 Preliminary Economic Assessment. Drilling commenced at West Goodspeed and will continue at Northwest Expo during the third quarter. This represents the fourth phase of Northwest Corridor drilling, following the Northwest Expo discovery hole in Phase I, the West Goodspeed discovery in Phase II, and resource definition at Northwest Expo in Phase III.

West Goodspeed drilling will test copper-gold mineralisation outlined over more than one kilometre of strike length oriented north-northwest to south-southeast. The programme allocates approximately 5,600 metres comprising at least seven infill holes and a minimum of three step-out holes. Previous drilling includes hole GS24-07, which intersected 154.8 metres grading 0.23% copper and 0.31 grams per tonne gold from 13.2 metres, and hole GS24-10, which returned 210 metres grading 0.23% copper and 0.29 grams per tonne gold from 46 metres, including 68 metres at 0.37% copper and 0.58 grams per tonne gold from 110 metres.

Northwest Expo field work and drilling will focus on identifying the intrusive associated with high-grade gold mineralisation in this segment. Ongoing soil geochemistry and geophysical inversions are refining drill targets, with drilling anticipated before the end of the third quarter.

Sam Lee, President and Chief Executive Officer, stated:

"We are pleased to have commenced our Phase IV drilling program with a focus on advancing a maiden resource at West Goodspeed and finding the intrusive at Northwest Expo. Northisle is in the envious position of having highly compelling exploration potential and an economically attractive development project, all within the same project footprint."

Regional Exploration and Target Definition Activities

The 2025 field programme includes surface mapping, soil and stream sediment sampling, and geophysical analysis across the Northwest Corridor. This work covers West Goodspeed, Northwest Expo, Red Dog, and Goodspeed areas. The integrated approach uses multiple data sources to identify potential extensions of porphyry mineralisation (a type of large-scale copper-gold deposit associated with intrusive rocks) within this segment of the belt.

Soil geochemistry and geophysical inversions at Northwest Expo are being conducted to refine targets potentially associated with the intrusive linked to the deposit. Integration of mapping, soil geochemistry, and geophysical data is expected to refine drill targets ahead of drilling in the third quarter.

Dr. Pablo Mejia Herrera, Vice President Exploration, stated that:

"In 2025, our exploration team will continue advancing our understanding of this district-scale project. Integration and modelling of more than 60 years of property-wide exploration data is underway to apply the successful Northwest Corridor targeting approach across our 35-kilometre district."

The regional stream sediment survey aims to identify additional porphyry centres in the belt. Results from the Northwest Corridor soil geochemistry programme and the regional stream sediment survey are scheduled for the third quarter of 2025. Results of belt-wide geophysical data integration are expected in the second quarter of 2025.

Property-Wide Data Integration and Targeting Expansion

The company is conducting an integrated interpretation of over 60 years of exploration and geophysical data to extend the targeting approach used in the Northwest Corridor to other areas of the property. This work involves reviewing historical drilling, geochemical sampling, geophysical surveys, and geological mapping conducted across the North Island Project.

Regional-scale magnetic anomalies occur throughout the property. The technical team is evaluating these anomalies in conjunction with geochemical data, structural interpretations, and alteration patterns. The objective is to identify exploration targets across the 35-kilometre district using criteria derived from the Northwest Corridor discoveries.

The data integration work is designed to establish geological and geochemical criteria for target identification based on the West Goodspeed and Northwest Expo results. This systematic review encompasses data from previous operators dating back to when the Island Copper Mine was operational in the region.

Looking Ahead

The company has outlined exploration milestones for 2025. Initial drilling results from West Goodspeed are expected in the third quarter, along with results from Northwest Expo drilling. The Northwest Corridor soil geochemistry programme and regional stream sediment survey results are also scheduled for the third quarter. The company plans to commence a Phase V exploration programme in the third quarter of 2025.

Additional development milestones will be shared later in 2025. The company states it is maintaining ongoing engagement with indigenous rightsholders and local stakeholders. Northisle has scheduled several investor events through 2025, including Mining Investment of the North in Quebec City (3-5 June), broker and institutional site visits during summer 2025, and mining conferences in Colorado and Switzerland.

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