Anatacau Main Project - Brunswick Exploration

Project Introduction

Anatacau Main is one of Brunswick Exploration Inc.’s (BRW) highly prospective lithium hard-rock exploration assets located in Quebec’s James Bay–Eeyou Istchee region, a globally recognized jurisdiction for lithium exploration and development (Figure 1).

The Anatacau Main Project is strategically located 22 kilometers east of BRW’s Anatacau West Project and Rio Tinto’s Galaxy Project (Probable 37.3 Mt at 1.27% Li₂O, Indicated 18.1 Mt at 1.12% Li₂O and Inferred 55.9 Mt at 1.29% Li₂O), along a large-scale east–west-trending deformation corridor. This regional structure is known to control lithium-bearing pegmatite emplacement and extends across both the Anatacau West and Anatacau Main properties over a combined strike length of approximately 23 kilometers (Figure 2). The mineralization style of Anatacau Main closely mirrors that observed at Rio Tinto’s Galaxy lithium project, reinforcing the geological continuity and district-scale potential of the Project.

In the fall of 2022, BRW entered into an option agreement with Osisko Development Corp. (TSX-V: ODEV) to acquire a 90% interest in the Anatacau Property, securing a strategic land position within an emerging lithium district.

During the summer of 2023, BRW announced the discovery of a significant spodumene-bearing pegmatite outcrop, known as the Anaïs Showing, measuring at least 100 metres in strike length and approximately 15 metres in width at surface. The Anaïs Showing occurs within a cluster of pegmatite dykes, all of which host high-grade lithium mineralization, highlighting the robust nature of the mineralized system (see July 13^th, 2023, press release).

The project’s strategic location, geological setting, and demonstrated high-grade mineralization position Anatacau Main as a high-impact exploration opportunity within Quebec’s rapidly advancing lithium sector.

Figure 1: Map of BRW projects and other lithium projects in the James Bay area.

Figure 2: Regional map of the Anatacau Main and Anatacau West projects.

Drilling

Brunswick Exploration completed two drill programs to date at the Anais Showing, most recently in the spring of 2026. A total of thirteen diamond drill holes have been drilled, recovering 2,603 meters, with significant lithium mineralization intersected in majority of the holes.

Drilling returned excellent lithium intercepts, including 120.7 metres grading 1.31% Li₂O (see November 17^th 2025 press release) and 167.9 meters grading 1.02% Li₂O including intercepts of 90.5 meters at 1.31% Li₂O and 58.5 meters at 1.60% Li₂O (see April 15^th 2026 press release) (Figure 3).

The most recent drill program confirmed the lateral continuity of the main spodumene-bearing Anais dyke. Extending the dyke over 350m in strike length with a vertical depth of 200 meters and a width of approximately 40 meters (Figure 4). Step-out drilling intersected a stacked pegmatite system with multiple large, well-mineralized pegmatites delineated over an area of approximately 350 meters wide by 600 meters long (Figures 5, 6 and 7).

These encouraging drilling results demonstrate substantial thicknesses and robust grades, highlighting the discovery potential of the Anais Showing. The Company is now planning further drilling in late Q3 of 2026.

Table – Anatacau Main Collars 2026-06-10

Table – Anatacau Main Intervals 2026-06-10

Figure 3: Surface map of the Anatacau Main project area with completed drill holes and intercept values.

Figure 4: Surface map of the Anatacau Main project area with Anais Main dyke surface projection interpretation and cross section locations.

Figure 5: Cross section A-A' (see Figure 4 for localization, section is 100 m thick).

Figure 6: Cross section B-B' (see Figure 4 for localization, section is 90 m thick).

Figure 7: Cross section C-C' (see Figure 4 for localization, section is 60 m thick).