Mr. Ian Klassen reports

GRANDE PORTAGE RESOURCES INITIATES FULL SCALE GEOCHEMICAL CHARACTERIZATION PROGRAM AND BACKFILL TESTWORK FOR THE NEW AMALGA GOLD PROJECT

Grande Portage Resources Ltd. has initiated a formal, comprehensive geochemical characterization program to advance permitting for the New Amalga gold property in southeastern Alaska, with samples shipped on April 24.

Geochemical characterization is a standard environmental study for metals mining projects. This test work determines whether any of the different types of rock to be produced by the project have the potential to be reactive (acid-generating leading to metals release) over the long term. Previous limited test work on a small number of New Amalga wallrock samples conducted in 2020/2021 showed favourable results, demonstrating significant net-acid-neutralizing ratios with all samples tested (Table 1).

The current program will test a far larger number of samples that are representative of the different rock types in the areas planned to be extracted under the preliminary economic assessment (PEA) mine plan (with an effective date of Feb. 11, 2026). Lab work will be performed by SGS North America, with program design and technical oversight provided by Stantec Consulting Services Inc.

In the PEA mine plan, all development rock and ore-sorter rejects produced by the mine are to be returned underground, primarily in the form of cemented rock fill (CRF) backfill, with no waste rock left on surface stockpiles after closure. Accordingly, the testing program will also include the first-ever creation of CRF utilizing New Amalga material. Crushed rock samples will be mixed with cement and cast into cylinders, which will undergo both geochemical testing as well as uniaxial compressive strength (UCS) crush testing. This will assess the strength of the backfill and help determine the cement content required to provide the necessary structural support for mining.

Ian Klassen, president and chief executive officer, commented: "The initiation of the geochemical program is a significant milestone in the progression of our environmental studies. The results of this program will be key inputs for the federal NEPA [National Environmental Policy Act] environmental review process as well as State of Alaska mining permits. The backfill testing will also provide critical data to inform future engineering and costing studies. We are pleased that the project continues to gather momentum following the outstanding results from our PEA released last month."

Project summary

The New Amalga gold project is located only 25 kilometres from Alaska's capital city of Juneau and six kilometres from paved highway. The resource remains open to expansion in multiple directions and hosts an indicated resource of 1,438,500 ounces of gold at an average grade of 9.47 grams per tonne gold (4,726,000 tonnes) and an inferred resource of 515,700 ounces of gold at an average grade of 8.85 g/t Au (1,813,000 tonnes) (with an effective date of July 17, 2024).

The current development concept envisions a small-footprint underground mining operation which would transport material off site for processing by a third party, eliminating the need for an on-site gold recovery plant or tailings storage facility.

This set-up is designed to provide several benefits:

• Eliminates the need to build a gold recovery plant, minimizing mine footprint, power requirements and reducing project construction capex (capital expenditures);
• Eliminates the need to develop a tailings disposal facility at the site as no tailings would be generated;
• Removes the need for permanent waste rock storage facilities; waste rock generated from mine development would be returned to the underground workings as stope backfill;
• No use of chemical reagents for gold processing at the site;
• Dramatically reduces land usage and overall environmental footprint;
• Greatly facilitates postmining closure and reclamation;
• Simplifies the environmental review and permitting process.

Project highlights:

• A 100-per-cent interest in the New Amalga gold project, located near infrastructure only 25 kilometres north of Juneau, Alaska, and six kilometres from paved all-season highway;
• The property is host to at least eight large, long, gold-bearing mesothermal veins;
• 240 drill holes from 55 platforms totalling approximately 65,000 metres confirm a large gold-quartz system;
• Past drilling produced multiounce assays on several veins; select samples include:
  • Deep Trench vein: 15.3 m grading 37.1 g/t Au, 8.3 m grading 58.6 g/t Au and 11.6 m grading 28.3 g/t Au;
  • Goat vein: 2.1 m grading 74.2 g/t Au and 6.3 m grading 15.7 g/t Au;
  • Main vein: 3.1 m grading 79.2 g/t Au, 2.1 m grading 37.2 g/t Au and 3.1 m grading 13.9 g/t Au;
  • Ridge vein: 1.5 m grading 43.0 g/t Au and 1.5 m grading 29.2 g/t Au;
  • Sleeping Giant vein: 2.1 m grading 15.4 g/t Au and 3.2 m grading 20.7 g/t Au;
• The company's updated National Instrument 43-101 mineral resource estimate (MRE) with an effective date of July 17, 2024, reported an indicated resource of 1,438,500 ounces of gold at an average grade of 9.47 g/t Au (4,726,000 tonnes) and an inferred resource of 515,700 ounces of gold at an average grade of 8.85 g/t Au (1,813,000 tonnes) as well as an indicated resource of 891,600 ounces of silver at an average grade of 5.86 g/t Ag (4,726,000 tonnes) and an inferred resource of 390,600 ounces of silver at an average grade of 7.33 g/t Ag (1,813,000 tonnes);
• The deposit is open to the north, south and at depth;
• Goat vein surface outcrop channel samples assayed 129.02 g/t Au (3.76 ounces per ton) and 290 g/t Au (8.46 ounces per ton) with 224 g/t Ag (6.53 ounces per ton);
• Lidar survey of property discovered numerous targets -- the first of these tested confirmed gold discovery;
• Received excellent metallurgical recoveries up to 98.2 per cent;
• Completed more than six years of environmental baseline water sampling;
• Current development strategy envisions a small-footprint underground mining operation with third party off-site processing, eliminating the need for an on-site mill or tailings storage facility; this configuration reduces capital costs, greatly minimizes the project's environmental footprint and facilitates permitting;
• LOI (letter of intent) signed with Goldbelt Inc. (an Alaska native corporation organized under the Alaska Native Claims Settlement Act) for development of an ore export terminal at Cascade Point, Goldbelt's privately held parcel located only 22 kilometres from the project site.

Kyle Mehalek, PE, is the qualified person within the meaning of NI 43-101 and has reviewed and approved the technical disclosure in this release. Mr. Mehalek is independent of Grande Portage within the meaning of NI 43-101.

About Grande Portage Resources Ltd.

Grande Portage Resources is a publicly traded mineral exploration company focused on advancing the New Amalga mine project, the outgrowth of the Herbert gold discovery situated approximately 25 kilometres north of Juneau, Alaska. The company holds a 100-per-cent interest in the New Amalga property. The New Amalga gold system is open to length and depth and is host to at least six main composite vein-fault structures that contain ribbon structure quartz-sulphide veins. The project lies prominently within the 160-kilometre-long Juneau gold belt, which has produced over eight million ounces of gold.

The company's updated NI 43-101 mineral resource estimate (MRE) reported at a base-case mineral resources cut-off grade of 2.5 g/t Au and consists of an indicated resource of 1,438,500 ounces of gold at an average grade of 9.47 g/t Au (4,726,000 tonnes) and an inferred resource of 515,700 ounces of gold at an average grade of 8.85 g/t Au (1,813,000 tonnes) as well as an indicated resource of 891,600 ounces of silver at an average grade of 5.86 g/t Ag (4,726,000 tonnes) and an inferred resource of 390,600 ounces of silver at an average grade of 7.33 g/t Ag (1,813,000 tonnes). The MRE was prepared by Dr. David R. Webb, PhD, PGeol, PEng (DRW Geological Consultants Ltd.), with an effective date of July 17, 2024. Additional information on the New Amalga mine project is available in the technical report titled "Technical Report of the Herbert Gold Property, Juneau District, Southeast Alaska," dated July 17, 2024, which is available under Grande Portage's SEDAR+ profile.

We seek Safe Harbor.