Defiance Silver Reports Up to 1,470 g/t Silver in Zacatecas Project Drilling Results

Outstanding Silver Grades Confirm Veta Grande System Expansion

Defiance Silver announced multiple high-grade silver intersections that reinforce confidence in the scale of the Veta Grande mineralized system at the Zacatecas Project. The standout result came from drill hole DDSA-26-85, which intersected 0.35 metres grading 1,470 g/t silver between 200.01 metres and 200.36 metres depth. This was part of a broader 4.28-metre interval averaging 136.23 g/t silver, alongside a secondary high-grade zone of 0.41 metres grading 1,175 g/t silver and 1.92 g/t gold from 240.31 metres to 240.72 metres.

Other notable intercepts include drill hole DDSA-26-83, which returned 2.60 metres at 227.00 g/t silver within an 8.48-metre interval averaging 132.87 g/t silver. This hole also intersected 4.18 metres grading 32.75 g/t silver and 0.79 g/t gold, with 1.32% lead and 4.12% zinc. Drill hole DDSA-26-88 revealed 0.35 metres of 641.00 g/t silver and 0.14 g/t gold within a 3.92-metre interval grading 166.03 g/t silver. These results indicate multiple mineralized horizons within the Veta Grande corridor, according to the company’s interpretation.

Structural Model Reveals Three Separate Mineralized Blocks

The drilling program has allowed Defiance to refine its geological model of the Veta Grande system. Interpretation of results identified at least three distinct structural blocks along the main vein corridor, each separated by major north- to northwest-trending fault systems. These blocks are designated as the Northwest Block (including Carolina and Almadén areas), the Central Block (covering Esperanza and Guadalupe areas), and the Southeast Block (stretching from Guadalupe through the Refugio-Tiro Intermedio sector). The company’s technical team believes this enhanced understanding of structural controls will guide future exploration and resource expansion efforts within the Zacatecas district.

The release notes that these fault systems have influenced vein displacement, mineralization styles, and the development of additional vein splays. Chris Wright, Chairman and CEO of Defiance Silver, stated, "Every drill hole adds to our understanding of the project, strengthens the geological model, and provides critical data for our upcoming Mineral Resource Estimate." The identification of multiple mineralized vein splays and confirmation of structural continuity support the company’s view of significant resource growth potential beyond historically defined boundaries.

Mineralization Extends Beyond Historical Resource Limits

Defiance initiated its current diamond drill program on September 12, 2025, aiming to enhance knowledge of the San Acacio resource area within the Zacatecas Project. The program focuses on refining the geological and structural model of the Veta Grande system, increasing confidence in areas with limited historical drilling, and assessing mineralized hanging wall and footwall vein splays. Several drill holes targeted zones between and adjacent to known mineralized areas, especially those with sparse historical data.

Drill hole DDSA-26-82, near the southeastern edge of the historical resource estimate, was designed to validate the updated geological interpretation. This hole successfully intersected both a significant mineralized hanging wall vein splay and the main Veta Grande structure, confirming mineralization continuity beyond previous limits. Similarly, drill hole DDSA-26-86 targeted an untested gap between shallow historical and deeper recent drilling west of the San José Fault, intersecting the Veta Grande system with high-grade silver mineralization. These results suggest potential for expanding the known mineralized footprint.

Structural Continuity Confirmed Between Major Pit Areas

Drill holes DDSA-26-84 and DDSA-26-85 were designed to test vein continuity between the Esperanza and Guadalupe pit areas, which have limited historical drilling. Both holes intersected broad zones of silver mineralization within intact veins, providing evidence of continuity along the Veta Grande system. The company views this as an opportunity for resource growth in this underexplored project section.

In the Northwest Block, drill hole DDSA-26-87 tested the interpreted displacement of the Veta Grande vein system by the San José Fault. Drilling confirmed the structural interpretation, validating vein geometry and continuity where surface exposures showed vein narrowing between two dilational zones. These findings bolster confidence in the evolving geological model and suggest structural understanding can guide future exploration.

Diamond Drill Program Progress and Remaining Targets

As of the announcement, the diamond drill program has completed 6,132 metres across 21 holes. Results from seven holes—DDSA-26-82 through DDSA-26-88—covering 1,700 metres are detailed in this release. A total of 4,658 metres of the planned 10,000-metre program have been reported. Samples from holes DDSA-26-89 through DDSA-26-92 have been submitted for assay analysis.

The remaining 3,868 metres will focus on testing highly prospective targets across the 4,217-hectare Zacatecas Project. This approach balances infill and extension drilling within known mineralized zones with exploration of new targets. The scale of the program highlights Defiance’s commitment to advancing the project and expanding its mineral resource base.

Quality Assurance and Analytical Methods

The release outlines quality assurance and quality control (QA/QC) procedures applied to drilling samples. Samples were selected based on lithology, alteration, and mineralization, with widths ranging from 0.25 to 2 metres. All altered and mineralized intervals were assayed. Each batch of 20 samples included one blank, one standard, and one duplicate, using certified reference materials from OREAS and CDN covering silver, gold, copper, lead, and zinc ranges.

No issues were detected in blanks, standards, or duplicates. Samples were analyzed by ALS Chemex Laboratories, with preparation at the Zacatecas, Mexico facility and analyses performed in Vancouver, Canada. Elements other than gold and mercury were analyzed via multi-element geochemistry using four-acid digestion and ICP-MS detection. Overlimit assays for silver, lead, and zinc used the OG62 method, while gold was measured by fire assay with ICP-AES finish on 50-gram samples.

Mineral Resource Estimate Preparation and Project Overview

The drilling campaign aims to validate the geological model for an upcoming Mineral Resource Estimate, though no timeline for its release has been provided. The results support the estimation process by confirming mineralization continuity, identifying structural controls, and expanding known mineralized zones. Defiance views these outcomes as strengthening confidence in the geological framework underpinning the resource estimate.

The Zacatecas Project covers 4,217 hectares in Mexico’s historic Zacatecas Silver District, a highly prospective area. The discovery of multiple mineralized vein splays, structural continuity, and expanded mineralized zones reinforce management’s view of significant resource growth potential. The company’s technical and management teams have extensive experience in exploring and developing operating mines and advanced projects.

Project Location and Operational Details

The Zacatecas Project is situated in Mexico’s historic silver mining district, with Defiance Silver holding a 100% interest. Besides Zacatecas, the company operates the Tepal Gold/Copper Project in Michoacán state and recently acquired the Green Earth Metals property portfolio in Sonora state. Defiance’s strategy focuses on capital-efficient exploration aimed at resource growth and new discoveries.

Drilling activities are concentrated at the San Acacio resource area within the Zacatecas Project, one of several mineralized zones on the property. The company maintains sample preparation facilities in Zacatecas and partners with international labs for analysis, enabling efficient execution of large-scale drilling and timely assay results to support ongoing geological modeling.

Management Insights on Project Potential and Strategy

Chris Wright, Chairman and CEO of Defiance Silver, commented on the drilling results: "These results continue to build our confidence in the scale and potential of the Veta Grande system. The discovery of high-grade silver mineralization beyond the historical resource area demonstrates the system is larger than previously understood and continues to offer new growth opportunities." The company views these findings as reinforcing the potential to expand resources and unlock additional value in the Zacatecas district.

The release highlights that the current drilling program is generating essential data for both the upcoming Mineral Resource Estimate and future exploration targeting. Management’s interpretation, identifying three distinct structural blocks with potential for further mineralized zones, provides a framework to prioritize future drilling and expansion. No updated resource estimates, production timelines, or forward-looking operational guidance were disclosed in this announcement.