Sun Summit Minerals Announces Completion of Exploration at the Theory Copper-Gold Project, Toodoggone Mining District, BC

September 29, 2026

Vancouver, B.C., Sept. 29, 2026: Sun Summit Minerals Corp. ("Sun Summit" or the "Company") (TSX-V: SMN; OTCQB: SMREF) is pleased to announce that it has completed its planned fieldwork for 2026 at its Theory copper-gold project (the "Theory Project"), located in north-central British Columbia.

The 9,676-hectare Theory Project borders Thesis Gold & Silver Inc.'s Ranch Project to the north and is located within 10 km to the northwest of Sun Summit's JD Project (Figure 1). Sun Summit signed an option agreement with Eagle Plains Limited (TSX-V:EPL) (OTCQB: EGPLF) to earn up to a 100% interest in the Theory Project, located in the highly prospective Toodoggone Mining District (see news release dated March 17, 2025).

Highlights from 2026 Field Program

• Prospecting results continued to reveal copper mineralization at the Saboteur Zone (Figure 2), a 3km long zone of chalcopyrite, bornite and chalcocite mineralization discovered in 2025, including THTHR094 (Figure 3), a 2026 grab sample of a massive blue calcite vein with bornite and native copper. The sample was collected approximately 250m SE of 2025 sample BLTHR029 which returned 1.44% copper, 0.043 g/t gold, 12.8g/t silver.
• Prospecting in the newly discovered Baguette Peak target area, approximately 600m SW of the Saboteur Zone, identified extensive copper mineralization, including chalcocite and chalcopyrite mineralization associated with a hydrothermally altered suite of volcanic rocks. Of particular note is THTHR086 (Figure 4), a sample of strongly epidote-altered basaltic andesite comprising copper mineralization including malachite, bornite, chalcocite and cuprite.
• A newly discovered zone north of Saboteur, named Misty Mountain, hosts numerous copper occurrences over a distance of 2.2 kms. The majority of mineralization is sub-vertically oriented calcite veins with variable amounts of malachite, bornite, chalcocite and cuprite (Figure 5 & 6).
• Airborne MagnetoTellurics geophysical survey ("MobileMT Survey") revealed strong anomalous resistivity associated with the Bev and Saboteur zones and aligns closely with anomalous copper samples taken in 2024 and 2025. The resistive zone seems also to closely map the presumed Jurassic-Triassic unconformity (~200 Ma), termed by the B.C. Geological Survey as the 'red-line', which is observed throughout the Golden Triangle and Toodoggone regions to have a high spatial correlation to many known mineral deposits.
• The IP survey targeted the Bev to Saboteur zones and also highlighted strong resistivity associated with the red-line unconformity and demonstrated a broad >500m chargeability anomaly (single line) under the Bev Zone, which overlaps with magnetic and resistive signatures, providing a priority target toward an interpreted causative source for anomalous copper in soil and rock samples taken over the past 2 seasons.
• A total of 218 rock grab samples, and 533 soil samples were collected in 2026. Geochemical and assay results are pending and will be reported after receipt and interpretation.

Niel Marotta, CEO, Sun Summit Minerals, commented: "Our successful three-phase exploration program at Theory, running alongside an aggressive 16,000-meter drill campaign at our flagship JD project, caps off an exceptional season of operational execution. Discovering widespread copper mineralization at the surface of newly discovered zones-backed by fresh ground IP and airborne MobileMT data-gives us a powerful toolkit to refine our targets and map out a historic, first-ever drilling campaign for 2027. We continue to unlock significant value at the highly under-explored Theory Project and look forward to updating the market as rock and soil results are received and interpreted."

Theory Project 2026 Exploration Program

The three phase 2026 fieldwork included a MobileMT Survey, a 20-day field program including prospecting, geological mapping, and geochemical sampling, and Induced Polarization (IP) geophysics in select target areas.

A total of 476 line-kilometers MobileMT Survey was completed at a nominal line spacing of 250 meters. The data allowed for high resolution of subsurface resistivity and assisted with planning for the follow-up ground IP survey. The MobileMT Survey was completed by Expert Geophysics Surveys Inc. of Newmarket, ON, under the guidance of geophysicist, Andrei Bagrianski, P.Geo.

An IP survey was completed over high-priority target areas, including the Bev and Saboteur Zones. The survey consisted of ~17.0-line kilometers on 8 variably spaced lines and was caried out by Peter E. Walcott and Associates Limited.

Coupled with previously flown helicopter-borne gradient magnetic and radiometric surveys (2024), the 2026 MobileMT Survey and ground IP data will improve the property-scale geophysical compilation and allow data interpretation to inform upcoming exploration decisions for the 2027 field season.

Fieldwork included mapping/prospecting and rock, soil, silt geochemical sampling, with crews based out of helicopter supported fly camps. Fieldwork was managed by TerraLogic Exploration Inc. of Cranbrook, BC, with helicopter and logistical support from the Company's JD Camp as required.

The results from the 2026 work program will be analyzed and modelled to identify and prioritize targets for 2027 drill testing.

Highlights from 2025 Field Program

2025 work included:

• Data Compilation with rectification and analysis of historical surface sampling and reconnaissance mapping.
• Remote sensing acquisition of district-and property-scale datasets, focusing on visible-near infrared and short-wave infrared bands to identify mineral groups diagnostic of epithermal and porphyry alteration.
• Field program consisting of prospecting, detailed geological mapping, and systematic rock, soil, and silt geochemical sampling on targets identified through data analyses.

Saboteur Zone: New high grade copper discovery

• 3km long zone of copper mineralization associated with coincident magnetic high transition zone and strong radiometric potassic alteration anomaly.
• 15 rock samples returned over 1% Cu.
• Grab sample LSTHR040: 4.78% Cu, 0.635 g/t Au, 49 g/t Ag.
• Grab sample JBTHR059: 4.0% Cu, 0.596 g/t Au, 61 g/t Ag.
• Grab sample MHTHR037: 3.3% Cu, 4.3 g/t Au, 121 g/t Ag.

BEV Zone:

• Broad copper soil and silt geochemical anomaly associated with multiphase alteration
• Grab sample BLTHR029: 1.44% Cu, 0.043 g/t Au, 12.8g/t Ag.

Fred-DM-DMR Zone:

• 1.6 km x 3km zone of copper mineralization associated with barite veining.
• Grab sample BLTHR051: 6.42% Cu, 0.088 g/t Au, 99 g/t Ag.
• Grab sample JBTHR008: 0.65% Cu, 12.6 g/t Au, 3150 g/t Ag.

Petrographic analyses of 2025 samples identified strong epidote-chlorite-carbonate alteration directly associated with hypogene copper mineralization (chalcopyrite - bornite - chalcocite). This type of mineralization and alteration assemblage is interpreted to represent the inner shell of a porphyry system, which may indicate a proximal source for some of the Theory mineralization.

Figure 1. Map of the Toodoggone District showing the location of the JD, Theory and Orbit Projects in relation to other development and exploration projects. Data sourced from Thesis Gold & Silver Inc., TDG Gold Corp. and Centerra Gold Inc.'s respective corporate websites. The qualified person has been unable to verify the information and that the information is not necessarily indicative to the mineralization on the property that is the subject of the disclosure.

Figure 2. Theory Compilation Map highlighting prospective zones and the newly discovered Baguette and Misty Mountain zone of copper mineralization.

Figure 3. Rock Sample THTHR094: calcite vein with epidote, bornite and native copper

Figure 4. Rock Sample THTHR086: strongly epidote altered basaltic andesite with bornite, chalcocite and cuprite

Figure 5. Misty Mtn Zone: Sample AOTHR044: chrysocolla and chalcocite in veinlets

Figure 6. Misty Mtn Zone: Rock Sample THTHR123: chrysocolla with blebby chalcocite

National Instrument 43-101 Disclosure

This news release has been reviewed and approved by Sun Summit's Vice President Exploration, Ken MacDonald, P. Geo., a "qualified person" as defined in National Instrument 43-101 - Standards of Disclosure for Mineral Projects of the Canadian Securities Administrators. Some technical information contained in this news release is historical in nature and has been compiled from public sources believed to be accurate. The historical technical information has not been verified by Sun Summit and may in some instances be unverifiable dependent on the existence of historical drill core and grab samples. Historical results are no indication of future results.

Community Engagement

Sun Summit is engaging with First Nations on whose territory our projects are located and is discussing their interests and identifying contract and work opportunities, as well as opportunities to support community initiatives. The Company looks forward to continuing to work with local and regional First Nations with ongoing exploration.

About the Theory Project

The Theory Project comprises 23 mineral claims covering 9,676 hectares. The project is located in north-central B.C. within the Toodoggone Mining District and is in close proximity with Sun Summit's JD Project. The Theory Project area shares similar geology to the JD Project and Thesis Gold & Silver's Ranch-Lawyers Projects. The Theory Project is helicopter-accessible and recent road upgrades completed in 2023 by Thesis Gold & Silver Inc. has brought road access to within 8 kilometres of the southern boundary of the Theory Project. Sun Summit signed an option agreement with Eagle Plains Resources Ltd. to earn up to a 100% interest in 10,000 hectares of mineral claims in the highly prospective Toodoggone Mining District, British Columbia (see news release dated March 17, 2025).

Geology in the Theory Project region is primarily comprised of lower Jurassic Hazelton Group volcanics (Toodoggone Formation, same host rock as the JD Project) which unconformably overlie late Triassic Takla Group volcanics. The entire package of volcanic and volcaniclastic rocks is intruded by late Triassic and early Jurassic stocks. The Jurassic-Triassic unconformity (~200 Ma), termed by the B.C. Geological Survey as the 'red-line', is observed throughout the Golden Triangle and Toodoggone regions to have a high spatial correlation to many known mineral deposits. The majority of the property encompasses this highly prospective contact.

About the JD Project

The JD Project is located in the Toodoggone mining district in north-central British Columbia, a highly prospective deposit-rich mineral trend. The JD Project covers an area of over 15,000 hectares and is in close proximity to active exploration and development projects, such as Thesis Gold and Silver Inc.'s Lawyers and Ranch projects, TDG Gold Corp's Baker-Shasta projects, Amarc Resource Ltd.'s AuRORA project, Centerra's Gold Inc's Kemess East and Underground projects, as well as the past-producing Kemess open pit copper-gold mine (Figure 1).

The JD Project is 450 kilometres northwest of the city of Prince George, and 25 kilometres north of the Sturdee airstrip. It is proximal to existing infrastructure in place to support the past-producing Kemess mine, including roads and a hydroelectric power line.

The JD Project is in a favourable geological environment characterized by both high-grade epithermal gold and silver mineralization, as well as porphyry-related copper and gold mineralization. Some historical exploration, including drilling, geochemistry and geophysics, has been carried out on the property, however the project area is largely underexplored.

About Sun Summit

Sun Summit Minerals (TSX-V: SMN; OTCQB: SMREF) is a mineral exploration company focused on the discovery, expansion, and advancement of district-scale gold and copper assets in British Columbia. The Company's portfolio is anchored by its flagship JD Project, alongside the Theory Project, and Orbit Project in the prolific Toodoggone region of north-central BC, and the Buck Project in central B.C.

Further details are available at www.sunsummitminerals.com.

Reference Link to Figures

Figure 1. https://wp-sunsummitminerals-2024.s3.ca-central-1.amazonaws.com/media/2026/08/SMN-Area-Map-Aug-2026.png

Figure 2. https://wp-sunsummitminerals-2024.s3.ca-central-1.amazonaws.com/media/2026/09/SMN_Theory_Figure2_202609.pdf

On behalf of the board of directors

Niel Marotta
Chief Executive Officer & Director
[email protected]

For further information, contact:

Matthew Benedetto, Simone Capital
[email protected]
Tel. 416-817-1226

Forward Looking Information

Statements contained in this news release that are not historical facts may be forward-looking statements, which involve risks, uncertainties and other factors that could cause actual results to differ materially from those expressed or implied by such forward-looking statements. In addition, the forward-looking statements require management to make assumptions and are subject to inherent risks and uncertainties. There is significant risk that the forward-looking statements will not prove to be accurate, that the management's assumptions may not be correct and that actual results may differ materially from such forward-looking statements. Accordingly, readers should not place undue reliance on the forward-looking statements. Generally forward-looking statements can be identified by the use of terminology such as "anticipate", "will", "expect", "may", "continue", "could", "estimate", "forecast", "plan", "potential" and similar expressions. Forward-looking statements contained in this news release may include but are not limited to the timing and completion of the analysis and modelling of the results from the 2026 work program, and its use to identify and prioritize targets for 2027 drill testing. These forward-looking statements are based on a number of assumptions which may prove to be incorrect which, without limiting the generality of the following, include: risks inherent in exploration activities; the ability of the Company to find and verify any mineralization; volatility and sensitivity to market prices; fluctuations in metal prices. The forward-looking statements contained in this news release are made as of the date hereof or the dates specifically referenced in this news release, where applicable. Except as required by applicable securities laws and regulation, Sun Summit disclaims any intention or obligation to update or revise any forward-looking statement, whether as a result of new information, future events or otherwise, except as required by applicable securities laws. All forward-looking statements contained in this news release are expressly qualified by this cautionary statement. Further details about the risks applicable to the Company are contained in the Company's public filings available on SEDAR+ (www.sedarplus.ca), under the Company's profile.

Neither the TSX Venture Exchange (the "TSXV") nor its Regulation Services Provider (as that term is defined in the policies of the TSXV) accepts responsibility for the adequacy or accuracy of this release.

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