Bonterra Reports Significant Mineral Resource Growth at Bachelor and Moroy, 100% owned Deposits and Provides Corporate Updates

Press Release

Val-d’Or, QC – April 1st, 2026 – Bonterra Resources Inc. (TSX-V: BTR, OTCQX: BONXF, FSE: 9BR2) (“Bonterra” or the “Company”) is pleased to announce updated Mineral Resource Estimates (the “2026 MREs”) for the Bachelor and Moroy Deposits at its 100% owned Desmaraisville Gold Project. The 2026 MREs were independently prepared by P&E Mining Consultants Inc. (“P&E”) on behalf of the Company in accordance with National Instrument 43-101 – Standards of Disclosure for Mineral Projects (“NI 43-101”) and are effective as of February 18, 2026.

Key Highlights

• Bachelor and Moroy combined 2026 MREs of 228 thousand ounces (“koz”) of Measured & Indicated Mineral Resources at an average grade of 3.98 g/t Au contained within 1.78 million tonnes (“Mt”), and
  133 koz of Inferred Mineral Resources at an average grade of 4.23 g/t Au contained within 0.978 Mt.
• Combined contained gold ounces increased by 42% in Measured & Indicated Mineral Resources and by 28% in Inferred Mineral Resources relative to the 2021 Mineral Resource Estimates (the “2021 MREs”).
• Bachelor MREs (Underground): 113 koz of Measured & Indicated Mineral Resources grading 3.87 g/t Au within 0.905 Mt, and 28 koz of Inferred Mineral Resources grading 4.45 g/t Au within 0.197 Mt.
• Moroy MREs (Underground): 115 koz of Measured & Indicated Mineral Resources grading 4.10 g/t Au within 0.875 Mt, and 105 koz of Inferred Mineral Resources grading 4.18 g/t Au within 0.781 Mt.

Marc-André Pelletier, President and CEO commented: “The discovery of the extension of the Hewfran mineralized zone last year, combined with the additional drilling completed since 2021, has enabled P&E to estimate these updated MREs for the Bachelor and Moroy Deposits, owned at 100%. The increase in MREs on our mining concession and mining lease, located near the Bachelor Mill, is significant, with now more than 113,000 ounces of gold in the Measured & Indicated category. Importantly, all Mineral Resources are located within 900 metres of the Bachelor Mill Complex, thereby offering a strategic opportunity to advance the restart of mining operations by leveraging already permitted infrastructure. The Company intends to begin its 2026 exploration program at Desmaraisville soon, which will aim to continue testing high-potential targets.”

2026 MREs Details & Assumptions

Data Analysis

• The 2026 MREs include new drilling completed by Bonterra from 2023 to 2025, including 9,799 m drilled containing 3,197 assays at Bachelor and 7,962 m drilled containing 1,663 assays at Moroy.
• A total of 2,432 drill holes and 379,577 m drilled containing 60,436 assays are considered for the Bachelor Deposit and 579 drill holes and 150,886 m drilled containing 18,185 assays for the Moroy Deposit.
• Revision of the capping threshold for mineralized zones based on geological and structural groupings.
• A more robust classification strategy based on field observations, historical mine records, oriented drill core and detailed variography.

Geology Interpretation and Modelling

• Revised modelling interpretations resulting from oriented core drilling, including the new delineated Hewfran Zone, and Bachelor wireframes showing increased deposit understanding over 2021.
• Revised modelling interpretations and cut-off resulting from increased gold price.
• Increased minimum mining width from 1.20 m to 1.75 m now more closely aligned with industry standards.
• All blocks within the 2026 underground MREs are constrained by optimized stope shapes as recommended by the CIM Estimation of Mineral Resources and Mineral Reserves Best Practice Guidelines.

The table below shows the comparison between the 2021 and 2026 MREs:

Table 1: Bachelor and Moroy deposits – Comparison of Mineral Resources in 2021 MREs with 2026 MREs^(1-6)

Notes:

1. 2021 MREs are estimated using a cut-off grade of 2.6 g/t Au for underground.
2. 2021 underground MREs were not constrained by stope shapes.
3. 2026 MREs are estimated using a cut-off grade of 2.0 g/t Au for underground stopes that constrain all blocks being reported.
4. 2021MREs and 2026 MREs are estimated using long-term gold prices of US$1,600 per oz and US$2,850 per oz, respectively.
5. Exchange rates used were US$/C$ of 0.75 for the 2021 MREs and 0.72 for the 2026 MREs.
6. Numbers may not sum due to rounding.

Bachelor Deposit MRE

The Bachelor MRE is based on 31 veins grouped within four steeply dipping vein sets from the surface to 1,000 m in depth, within which 1 m capped composites have been calculated and grade blocks estimated with a multi-pass inverse distance cubed (“ID3”) interpolation method (see Table 2). Measured Mineral Resources were defined where proximal to historical workings and using three drill holes spaced up to 15 m apart. Indicated Mineral Resources were limited to areas defined using three drill holes spaced up to 30 m apart. Inferred Mineral Resources represent areas with drill hole spacing up to 60 m. Mineral Resources are reported within underground reporting optimized stope shapes constructed using a minimum thickness of 1.75 m and a gold cut-off grade of 2.0 g/t Au and limited to areas of continuous mineralization. Mineral Resources were depleted within 5 m of historical mined out stopes. In addition, a 2 m buffer solid was created around all mineralized wireframes to capture any marginal grade for underground stope optimization internal dilution. All blocks within the underground constraining optimized stope shapes have been included within the Mineral Resources Estimate at a zero cut-off grade.

Table 2: Bachelor Deposit 2026 MREs^(1-12)

Notes:

1. CIM definitions were followed for Mineral Resources.
2. Mineral Resources are presented externally undiluted and in situ and are considered to have reasonable prospects for eventual economic extraction. The underground Mineral Resources are constrained by potentially mineable stope shapes.
3. Underground Mineral Resources stope shapes are optimized at a cut-off of 2.0 g/t Au.
4. Mineral Resources are estimated using a long-term gold price of US$2,850 per oz and a US$/C$ exchange rate of 0.72.
5. A minimum mining width of 1.75 m was used.
6. Mineral Resources were depleted within 5 m of historical mined out stopes.
7. Assay samples were composited within the mineralization envelopes into 1 m length composites. A value of
   0.001 g/t Au was applied in cases of drill core not assayed.
8. High-grade outliers were established using a statistical analysis on a per-zone basis for gold on composite data.
   Capping varied from 40 to 45 g/t Au and was applied on composites within each specific wireframe.
9. Bulk density values were applied on the different mineralized zones varied from 2.79 to 2.82 t/m³ based on site drill core measurements with a mean value of 2.81 t/m³ used for reporting purposes.
10. ID3 block grade interpolation was used.
11. Grade estimates are based on a parent block dimension of 2 m x 4 m x 4 m with sub-cells down to 0.25 m x 1 m x 1 m. Search parameters were determined by variography.
12. Numbers may not sum due to rounding.

Figure 1: Bachelor 2026 MRE Longitudinal Projection View Looking Northeast

Moroy Deposit MRE

The Moroy MRE is based on 11 vein structures and clusters within two structural groups. Block model grade estimates are controlled by the geological/vein interpretations and were completed using a three-pass ID3 block grade interpolation method and capped 1 m composites (see Table 3). Measured Mineral Resources were defined using three drill holes spaced up to 15 m apart. Indicated Mineral Resources are limited to areas defined using three drill holes spaced up to 30 m apart. Inferred Mineral Resources represent areas with drill hole spacing and extrapolation up to 60 m. Mineral Resources are reported within underground reporting shapes constructed using a minimum thickness of 1.75 m and a cut-off grade of 2.0 g/t Au, limited to areas of continuous mineralization. Mineral Resources were depleted within 5 m of historical mined out stopes. In addition, a 2 m buffer solid was created around all mineralized wireframes to capture any marginal grade for underground stope optimization internal dilution. All blocks within the underground constraining optimized stope shapes have been included within the Mineral Resources Estimate at a zero cut-off grade. Grade blocks within a 50 m crown pillar below the base of overburden has been excluded from the Mineral Resources.

Table 3: Moroy Deposit 2026 MREs^(1-13)

Notes:

1. CIM definitions were followed for Mineral Resources.
2. Mineral Resources are presented externally undiluted and in situ and are considered to have reasonable prospects for eventual economic extraction. The Underground Mineral Resources are constrained by potentially mineable stope shapes.
3. Underground Mineral Resources are estimated at a cut-off of 2.0 g/t Au.
4. Mineral Resources are estimated using a long-term gold price of US$2,850 per oz and a US$/C$ exchange rate of 0.72.
5. A minimum mining width of 1.75 m was used.
6. Mineral Resources were depleted within 5 m of historical mined out stopes.
7. Assay Samples were composited within the mineralization envelopes into 1 m length composites. A value of 0.001 g/t Au was applied in cases of drill core not assayed.
8. High-grade capping was done on composite data and established using a statistical analysis on a per-zone basis for gold. A 30 g/t Au capping was applied on composites within each specific wireframe.
9. Bulk density values were applied on the different mineralized zones varied from 2.68 to 2.87 t/m³ based on-site drill core measurements with a mean value of 2.80 t/m³ used for reporting purposes.
10. ID3 block grade interpolation was used.
11. Grade estimates are based on a parent block dimension of 2 m x 4 m x 4 m with sub-cells down to 0.25 m x 1 m x 1 m. Search parameters were determined by variography.
12. A 50 m crown pillar was applied at Moroy.
13. Numbers may not sum due to rounding.

Figure 2: Moroy 2026 MRE Longitudinal Projection View Looking Northwest

Summary and Validation

Mineralized domains were initially developed by Bonterra and then reviewed, modified and accepted by P&E.
All Mineral Resource domains were defined within Leapfrog Geo^TM software and sub-block model grade estimates were completed within Leapfrog Edge^TM. Underground constraining shapes at Bachelor and Moroy were optimized using Deswik^TM stope optimizer software. In addition to standard database validation techniques, wireframe and block model validation procedures, including wireframe to block volume confirmation, statistical comparisons with composite and nearest neighbour grade estimates, swath plots, visual reviews in 3D, longitudinal projection, cross-section, and plan views, and cross software reporting confirmation, were completed for all deposits.

The Qualified Person (“QP”) considers the geological modelling, grade estimation, and Mineral Resources classification considered in these Mineral Resources estimates to be consistent with industry practice and aligned with the CIM Estimation of Mineral Resources and Mineral Reserves Best Practices guidelines, as recommended by Canadian Securities Administrators’ National Instrument 43‑101. Mineral Resources are not Mineral Reserves and do not have demonstrated economic viability.

Further details regarding the 2026 MREs, key assumptions, parameters and methods used to estimate the Mineral Resources of the Bachelor and Moroy Deposits will be available on SEDAR+ (www.sedarplus.ca ) under the Corporation’s issuer profile within 45 days of this news release in accordance with NI 43-101.

Corporate Update

The press release of the Company dated March 23, 2026 disclosed a credit facility (the “Credit Facility“) provided by certain funds managed by Wexford Capital LP in an aggregate amount of C$5,000,000. The Company wishes to provide the following additional disclosure in respect of this unsecured Credit Facility. No bonus securities and/or other finder’s fee will be paid in connection with the Credit Facility, other than the previously disclosed C$100,000 commitment fee.

Independent Qualified Person

The Mineral Resources Estimate was prepared by P&E. The QP has reviewed and approved the content of this news release. Independent QP Antoine Yassa, P. Geo, OGQ of P&E has prepared and supervised the preparation of the technical information relating to this Mineral Resources Estimate.

Bonterra Qualified Person and QAQC

M. Donald Trudel, P. Geo. (OGQ # 813), Director of Geology for the Company, has reviewed and approved the technical information contained in this press release. Mr. Trudel is a Qualified Person as defined by National Instrument 43-101 on standards of disclosure for mineral projects.

The Bachelor and Moroy Project’s drill core gold analyses were performed at the Bachelor Mine Laboratory, Actlabs (at Ste-Germaine-Boulé), AGAT Laboratories and at MSALABS both located in Val d’Or, Québec. The Company’s laboratory and external laboratories employ a rigorous QAQC analysis program that meets industry standards. The analyses were carried out by fire assay with atomic absorption finish at Bachelor Mine Laboratory and with gravimetric finish for assay above 10 g/t Au at Actlabs and AGAT laboratories. Blanks, duplicates, and certified reference materials were inserted into the sample stream to monitor the laboratory’s performance.  At MSALABS laboratory, the samples were crushed to a particle size of 70% passing through a two-millimetre sieve, and then a 500-gram portion was taken for gold analysis by gamma ray (PhotonAssay^TM). As per MSALABS’ internal procedure, blank samples, and certified reference materials were systematically inserted into the sample sequence for analysis. MSALABS operates several laboratories worldwide and holds ISO-17025 accreditation for numerous metal determination methods, including the photon assay method. The Company’s QAQC program requires that at least 5% of samples be analyzed by an independent laboratory. These verification samples were sent to ALS Minerals’ laboratory facility located in Val-d’Or, Québec. The verifications show a high degree of correlation with the Laboratory’s results.

ABOUT P&E MINING CONSULTANTS INC.

P&E, established in 2004, provides geological and mine engineering consulting reports, Mineral Resources Estimate technical reports, Preliminary Economic Assessments and Pre-Feasibility Studies. In addition, we are affiliated with major consulting firms for the purposes of joint venturing on Feasibility Studies. Our experience covers over 480 technical reports on diamonds, most metallic deposits including gold, silver, base metals, PGM and iron for both open pit and underground deposits. Software packages utilized include Gemcom, Leapfrog, Whittle, NPV Scheduler, Vulcan, Ventsim, AutoCAD and Deswik. P&E’s 22 associates have experience in geological interpretation, 3D geological modelling, technical report writing, Mineral Resources and Mineral Reserves Estimates, property evaluations, mine design, production scheduling, operating and capital cost estimates, and metallurgical engineering.

ABOUT BONTERRA

Bonterra is a Canadian gold exploration company with a portfolio of advanced exploration assets anchored by a central milling facility in Québec, Canada. The Company’s assets include the Gladiator, Barry⁽¹⁾, Moroy, and Bachelor gold deposits, which collectively hold 16.8 million tonnes (“Mt”) at an average grade of 3.02 g/t Au for 1.63 million ounces (“Moz”) of Measured & Indicated Mineral Resources, plus 15.6 Mt at an average grade of 4.32 g/t Au for 2.17 Moz Au of Inferred Mineral Resources.

In November 2023, the Company entered into an earn-in and joint venture agreement with Osisko Mining Inc. (“Osisko Mining”) for the Urban-Barry properties (the “JV Agreement”), which include the Gladiator and Barry deposits. In October 2024, Gold Fields Ltd, through a wholly owned Canadian subsidiary, completed the acquisition of Osisko Mining for C$2.16 billion. Gold Fields is now the counterparty to the JV Agreement and can continue to earn a 70% interest in the joint venture by incurring C$30 million in work expenditures on or before November 2026 (including expenditures incurred by Osisko Mining prior to October 2024). This strategic transaction highlights Bonterra’s dedication to advancing its exploration assets, marking a significant step towards development.

⁽¹⁾ See our press release from February 23, 2026, titled “Bonterra Reports Significant Mineral Resources Growth at Barry and Gladiator Deposits” for further details.

FOR ADDITIONAL INFORMATION

Marc-André Pelletier, President & CEO
ir@btrgold.com

2872 Sullivan Road, Suite 2, Val d’Or, Québec J9P 0B9

819-825-8678 | Website: www.btrgold.com

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