Further High-Grade Silver Discovered Beyond Current MRE - Sun Silver (ASX: SS1 | OTCQX: SSLVF)

Drilling continues to deliver broad high-grade silver beyond the current MRE, confirm extensive antimony mineralisation and highlight further resource growth potential.

Highlights:

• MR25-235: 98.3m at 120.3g/t AgEq (65.7g/t Ag and 0.67g/t Au) from 173.0m, including: 47.6m at 200.6g/t AgEq (119.6g/t Ag and 1.05g/t Au) from 176.8m
• MR25-235 also intercepted mineralisation outside the MRE, with results up to 811.7g/t AgEq (769g/t Ag and 0.5g/t Au).
• Results for MR25-235 also demonstrate consistent antimony zones throughout including: 86.9m at 0.10% Sb from 175.3m, with individual assays up to 1.23% Sb 
• Drilling continues to increase confidence in the Company's geological and mineralisation models by intersecting predicted mineralised zones and testing open extensions.

PERTH, Australia, Aug. 19, 2026 /PRNewswire/ -- Sun Silver Limited (ASX: SS1) (OTCQX: SSLVF) ("Sun Silver" or "the Company") is pleased to report assays from its ongoing 2026 exploration program at the Maverick Silver Project in Nevada, USA ("Maverick" or "the Project").

Sun Silver Managing Director, Andrew Dornan, said: 

"Our latest drilling at the Maverick Silver Project in Nevada has delivered an exceptional 98.3m at 120g/t AgEq, including 47.6m at 201g/t AgEq, with the intercept starting outside the current Mineral Resource and highlighting significant resource growth potential. The associated 86.9m antimony zone averaging 0.1% Sb, with grades up to 1.2% Sb, further demonstrates the scale and multi-element potential of the Maverick mineralised system."

Table 1 – Significant Down Hole Drilling Intercepts

Additional drill results have been received from the Maverick Silver 2026 drill program, with complete assays returned for MR25-235 and MR26-226, drilled within the south-central zone of the Mineral Resource to increase confidence in the continuity and distribution of mineralisation in this area.

Table 2 – Antimony Interval Highlights

The 2026 drill program was designed to advance the Maverick Silver Project across three key priorities:

• Priority 1 – Resource Classification Upgrade: targeted infill drilling to improve geological confidence and support conversion of the existing Mineral Resource to the JORC Indicated category;
• Priority 2 – Development Advancement: collection of additional metallurgical core to support ongoing development studies and future processing pathways; and
• Priority 3 – Resource Growth: step-out drilling targeting the north-west extension of the high-grade hinge-zone mineralisation and other open extensions of the system.

The results reported in this announcement continue to deliver against these objectives, with drilling intersecting extensive zones of silver and gold mineralisation while validating the Company's evolving geological model. Importantly, high-grade silver mineralisation has been intersected beyond the current Mineral Resource, supporting the potential for future resource growth along the northwest structural corridor.

Drill hole MR25-235 was drilled as a twin hole to verify the tenor of mineralisation from a historic RCD hole completed by Angst in 1990 (MR102). This was drilled as part of the company's validation work to test data in the legacy database. The two drill holes, MR102 and MR25-235, were composited to 1m intervals and plotted against each other in QQ plots to assess the grade distribution with both having a broadly similar 100m intercept starting from 173m and 175m depth respectively. The historic Angst drill hole had a portion of pulps re-analysed by Sun Silver, but majority of the drill hole assays are from the historic database. The QQ plot showed a slight bias towards a higher AgEq grade in the 2026 drill hole which has been drilled to current industry standards, with modern analytical techniques and adequate QAQC. The silver analysed separately showed a very similar distribution, with a high-grade outlier in favour of the 2026 drilling (not on graph). The gold appears to have slight bias towards higher grades in the 2026 results influencing the AgEq grade. It is important to note that the gold in the historic Angst dataset still has a ~20% regression applied due to uncertainty in the historic grades stemming from previous work by Snowden and SGS. The whole-hole multi-element analysis in MR25-235 also identified a significant antimony zone which was not apparent from the historic drill hole with only silver and gold analysed. These results provide confidence in the historic database and further enhance the Company's understanding of the mineralised system while highlighting the potential for continued resource growth.

2026 Development Roadmap

2026 represents a pivotal year for the advancement of the Maverick Silver Project as the Company progresses toward development through the delivery of key technical, permitting and study milestones, including:

• Advancing the Mineral Resource toward JORC Indicated classification through infill drilling;
• Expanding the Mineral Resource through targeted step-out drilling;
• Advancing metallurgical testwork to optimise heap leach processing pathways;
• Completing geotechnical, hydrogeological and geochemical programs to support future development studies;
• Progressing environmental permitting and baseline studies;
• Advancing mine planning, including pit optimisation and mine design;
• Scoping Study – Targeting release end of 2026 / early 2027 pending progress of 2026 drilling program; and
• Pre-Feasibility Study – targeted following completion of the Scoping Study and continued advancement of the Mineral Resource, currently anticipated in 2027.

Note: The timing of the Scoping Study and Pre-Feasibility Study is dependent on the progress and outcomes of the ongoing infill drilling program and associated technical work.

Metal Equivalents

References to metal equivalents ("AgEq") are based on an equivalency ratio of 85, which is derived from a gold price of USD$2,433 and a silver price of USD$28.50 per ounce, being derived from the average monthly metal pricing for the last three years, and average metallurgical recovery. Therefore:

AgEq = Silver grade + (Gold Grade x ((Gold Price * Gold Recovery) / (Silver Price * Silver Recovery))) or,

AgEq (g/t) = Ag (g/t) + (Au (g/t) x ((2433 x 0.85) / (28.50 x 0.85)))

Metallurgical recoveries of 85% have been assumed for both silver and gold. Preliminary metallurgical recoveries were disclosed in the Company's Prospectus dated 17 April 2024, which included a review of metallurgical test work completed by the prior owners of the Maverick Silver Project. Metallurgical recoveries for both gold and silver were recorded in similar ranges, with maximum metallurgical recoveries of up to 97.5% in preliminary historical metallurgical testing in respect of silver and up to 95.8% in respect of gold. Gold recoveries were commonly recorded in the range of 80% - 90%, and the midpoint of this range has been adopted at present in respect of both silver and gold. It is the Company's view that both elements referenced in the silver and gold equivalent calculations have a reasonable potential of being recovered and sold.

Surface Geochemical Anomalism

Carlin-style mineral systems are recognised worldwide by characteristic pathfinder element zoning, with arsenic-antimony anomalism commonly occurring proximal to mineralisation and mercury-thallium anomalism occurring more distally.

Surface exploration across the broader Project area has continued to delineate compelling new exploration corridors extending well beyond the current Mineral Resource footprint.

Recent regional rock‑chip sampling has outlined a 2 km‑long anomalous trend marked by elevated antimony and arsenic assays accompanied by favourable alteration features characteristic of Carlin‑style mineralising systems. Located roughly 4.5 km north of the Maverick Mineral Resource, the 'Northern Target' is associated with silica alteration, decalcification and jasperoidal brecciation, and displays a geochemical signature comparable to surface samples above the Maverick Silver Deposit^[3].

Additional sampling has been completed to the north and south of the Maverick Mineral Resource, along the axial trend of the main mineralised fold hinge, highlighting that the mineral system is open along strike in both directions from the margins of the Mineral Resource (Figure 4).

Maverick Silver Project

Sun Silver's cornerstone asset, the Maverick Silver Project, is located 85km from the fully serviced mining town of Elko in Nevada and is surrounded by several world-class gold and silver mining operations including Barrick's Carlin Mine.

Nevada is a globally recognised mining jurisdiction which was rated as the Number 1 mining jurisdiction in the world by the Fraser Institute in 2025.

The Project, which is proximal to the prolific Carlin Trend, hosts a JORC Inferred Mineral Resource of 237Mt grading 45.5g/t Ag and 0.30g/t Au for 347.2Moz of contained silver and 2.25Moz of contained gold (539Moz of contained silver equivalent)^[4].

The deposit itself remains open along strike and at depth, with multiple mineralised intercepts located outside of the current Resource constrained model.

This announcement is authorised for release by the Board of Sun Silver Limited.

Forward-looking statements

This announcement may contain certain forward-looking statements, guidance, forecasts, estimates or projections in relation to future matters (Forward Statements) that involve risks and uncertainties, and which are provided as a general guide only. Forward Statements can generally be identified by the use of forward-looking words such as "anticipate", "estimate", "will", "should", "could", "may", "expects", "plans", "forecast", "target" or similar expressions and include, but are not limited to, indications of, or guidance or outlook on, future earnings or financial position or performance of the Company. The Company can give no assurance that these expectations will prove to be correct. You are cautioned not to place undue reliance on any forward-looking statements. None of the Company, its directors, employees, agents or advisers represent or warrant that such Forward Statements will be achieved or prove to be correct or gives any warranty, express or implied, as to the accuracy, completeness, likelihood of achievement or reasonableness of any Forward Statement contained in this announcement. Actual results may differ materially from those anticipated in these forward-looking statements due to many important factors, risks and uncertainties. The Company does not undertake any obligation to release publicly any revisions to any "forward- looking statement" to reflect events or circumstances after the date of this announcement, except as may be required under applicable laws.

Competent Person Statement

The Exploration Results reported in this announcement are based on, and fairly represent, information and supporting documentation reviewed, and approved by Mr Brodie Box, MAIG. Mr Box is a consultant geologist at Cadre Geology and Mining and has adequate professional experience with the exploration and geology of the style of mineralisation and types of deposits under consideration to qualify as a Competent Person as defined in the 2012 Edition of the Joint Ore Reserves Committee (JORC) Australasian Code for reporting of Exploration Results, Mineral Resources and Ore Reserves. Mr Box consents to the form and context in which the Exploration Results are presented in this announcement.

The information in this announcement that relates to previously reported Exploration Results or Estimates of Mineral Resources at the Maverick Silver Project is extracted from the Company's ASX announcements dated 24 September 2024, 14 January 2025, 26 March 2025, 2 July 2025, 19 August 2025, 3 September 2025, 15 October 2025, 20 November 2025, 26 November 2025, 9 December 2025, 23 July 2026 and 3 August 2026 (Original Announcements). The Company confirms that it is not aware of any new information or data that materially affects the relevant information contained in the Original Announcements and, in the case of Estimates of Mineral Resources, that all material assumptions and technical parameters underpinning the estimates continue to apply and have not materially changed.

SOURCE Sun Silver Ltd.