TORONTO, Sept. 10, 2026 /PRNewswire/ -- Hemlo Mining Corp. (TSX: HMMC) (OTCQX: HMMCF) ("Hemlo Mining" or the "Company") is pleased to announce additional assay results from its ongoing drilling program designed to support future mineral resource growth across the Hemlo Gold Mine ("Hemlo" or the "Mine"), located near Marathon, Ontario, Canada.

Additional assay results from the South-Rim Zone ("South-Rim") continue to define a newly recognized, high-grade mineralized domain with strong potential for near-term, low-capital resource growth. Drilling continues to intersect the interpreted South-Rim horizon, validating the Company's geological model and reinforcing South-Rim as a potential near-mine growth opportunity adjacent to active C-Zone mining.

Highlights:

- New South-Rim results include 89.89 g/t Au over 3.0 metres in hole 6702608, 14.81 g/t Au over 10.0 metres in hole 6702632 and 12.97 g/t Au over 7.0 metres in hole 6702615 (see Figure 1 and Table 1 for additional results).

- 2026 drilling has now demonstrated approximately 500 metres of high-grade mineralization within the interpreted 1.5-kilometre South-Rim Zone, leaving approximately 1 kilometre of additional extent to be tested and defined.

- South-Rim lies only 50 to 150 metres from active C-Zone mining and existing underground infrastructure, providing a potential pathway to near-term, low-capital resource growth.

- The upper extension projects toward the open-pit resource shell, creating potential to support both underground and open-pit resource growth.

- Strong results have led to an expanded program and the addition of Conversion drilling.

- South-Rim remains open along strike, down plunge and to the east and west, with deeper drilling planned for the fourth quarter of 2026.

- 2026 South-Rim drilling results were not included in the June 2026 Updated Mineral Resource Estimate (the "MRE") and these results are expected to support future Mineral Resource growth.

Jason Kosec, President, CEO & Director of Hemlo Mining, commented: "South-Rim is rapidly emerging as one of the most exciting near-mine growth opportunities at Hemlo. Since our initial results announced on May 14th, drilling has continued to deliver strong grades and meaningful widths where predicted, including 89.9 g/t Au over 3.0 metres and 14.8 g/t Au over 10.0 metres. We have now demonstrated approximately 500 metres of high-grade mineralization within the interpreted 1.5-kilometre zone, with substantial additional extent remaining to be tested. Its location, only 50 to 150 metres from active C-Zone mining, creates a potential pathway to low-capital resource growth. Based on the strength of the results, we have expanded the program and added Conversion drilling to potentially advance portions of the zone toward Indicated classification. South-Rim remains open and is expected to be an important contributor to our comprehensive Mineral Resource and Mineral Reserve update targeted for the second half of 2027."

Table 1. Selected Gold Intercepts from the 2026 South-Rim Drill Program1,2,3,4

- Totals may not sum due to rounding. Negative dips indicate holes drilled upward.

- True thickness is estimated to vary between 65% and 90% of downhole length.

- Drill intercepts are constrained to the interpreted mineralized envelope and include internal dilution and uncapped assays.

- Drill intercept locations are shown on Figures 1, 2 and/or 3 above.

Drilling Program Overview

In January 2026, the Company announced the initiation of a 130,000-metre exploration drilling program intended to serve as the foundation for an updated Mineral Resource and Mineral Reserve technical report expected in the second half of 2027. The program is structured across three complementary programs:

- 70,000 metres of Resource Conversion Drilling targeting the upgrade of Inferred Mineral Resources to the Indicated category;

- 30,000 metres of High-Definition Drilling to de-risk the near-term mine plan; and

- 30,000 metres of Growth Drilling designed to test new mineralized zones beyond the current resource footprint.

The program is advancing as planned, with seven drills currently operating underground and three at surface. Approximately 75,000 metres of drilling have been completed to date across all three programs. The broader 2026 exploration strategy is designed to grow Mineral Resources, extend mine life and identify near-mine, low-capital growth opportunities across Hemlo. Additional assay results from South-Rim and other active exploration areas, including the A-, B-, C-, D- and E-Zones, are expected over the coming months.

South-Rim Geology and Context of Results

South-Rim was identified as one of the Company's priority Growth Drilling targets in its January 2026 exploration drilling program announcement, based on geological interpretation and its proximity to existing underground infrastructure. The initial South-Rim program contemplated 20 Growth drill holes designed primarily to test and expand mineralization beyond the existing Mineral Resource footprint. Following the strength and consistency of the initial results, the Company expanded the program and, where warranted, tightened drill hole spacing through additional Conversion drilling to further define the mineralized system and advance as much of the mineralization as practical toward potential Indicated Mineral Resource classification. Drilling at South-Rim will continue as part of the Company's broader exploration and resource conversion programs.

The 2026 drilling confirms the South-Rim shoot at the scale previously interpreted (see Figure 1), with no material change to its defined dimensions. The Company believes South-Rim has the potential to extend significantly further east-west than currently drill-tested, including a potential B-Zone South-Rim structure that remains largely unexplored and, based on early geological interpretation, may host additional high-grade mineralized shoots.

The latest drilling has focused primarily on the upper portion of the C-Zone South-Rim shoot, immediately below mineralization reported earlier in 2026. Drilling planned over the coming months is expected to progressively test deeper portions of the interpreted system, while additional drilling in 2027 will be required to increase drill density across its broader extent.

The MRE incorporated refinements to the C-Zone geological interpretation based on historical drilling and geological information. While none of the 2026 South-Rim drilling was included in the MRE, historical mineralization within the area now interpreted as South-Rim supported limited Mineral Resource shapes. The latest drilling continues to confirm and expand this mineralization, locally returning grades above those represented by the existing resource model.

South-Rim's proximity to existing mine infrastructure (see Figures 2 and 3) has the potential to reduce both the capital cost and lead time required to advance any future Mineral Resources in the area, as development could leverage existing underground access rather than requiring new infrastructure.

At its upper extent, the interpreted South-Rim mineralization projects into the existing open-pit resource shell. Portions of this projected mineralization occur within material currently treated as waste due to limited drilling, although they lie within the future pit footprint. Surface drilling will be required to better define the shallow mineralization and assess its potential contribution to future open-pit Mineral Resources and potential to reduce the future pit strip ratio.

Beyond the currently defined South-Rim shoot, the Company continues to evaluate the broader South-Rim structural horizon across the Hemlo deposit. Geological interpretation suggests that similar mineralized shoots may occur toward the E-Zone; however, further compilation and drilling will be required to test this concept.

Next Steps

Growth drilling at South-Rim has continued to validate and expand the mineralized system, prompting the addition of Conversion (infill) drilling to potentially advance portions of the shoot toward Indicated classification. Additional Growth and Conversion drilling is planned through the fourth quarter of 2026 and into 2027 to further define the shoot, test extensions at depth and toward surface, and evaluate the broader South-Rim structural corridor. Located immediately adjacent to existing underground infrastructure and active C-Zone mining, South-Rim represents a compelling near-mine growth opportunity with the potential to contribute meaningfully to future resource growth and the comprehensive Mineral Resource and Mineral Reserve update targeted for the second half of 2027.

Corporate Update – Appointment of Vice President, Human Resources

The Company is also pleased to announce the appointment of Martin Rioux as Vice President, Human Resources, effective immediately.

Mr. Rioux is a seasoned human resources executive with more than 25 years of progressive HR experience, including over two decades in leadership roles across Canada, the United States and international mining operations. Throughout his career, Martin has partnered with executive teams to drive business performance, lead workforce transformation initiatives and build high-performing workplace cultures within complex, cross-cultural and multi-site operating environments.

Prior to joining the Company, Mr. Rioux began his career with Falconbridge (now Glencore) and later held senior HR leadership positions with Agnico Eagle, Nyrstar, Newmont and Magris Talc. His broad experience spans organizational transformation, business integrations, talent management, total rewards, HR systems and labour relations.

Mr. Rioux holds a Bachelor of Business Administration degree with a specialization in Human Resources Management and is a Certified Human Resources Professional (CHRP).

In his role, Mr.