Pinnacle conducts channel sampling at Dos de Mayo

Mr. Robert Archer reports PINNACLE DEFINES HIGH-GRADE GOLD-SILVER MINERALIZATION IN DOS DE MAYO MINE AT EL POTRERO Systematic underground channel sampling in the historic Dos de Mayo mine at Pinnacle Silver and Gold Corp.'s El Potrero project in Durango, Mexico, is providing a good look at the gold-silver distribution within the known mineralized zone. Fifty-three channel samples, in 13 composite channels, were taken within a raise (inclined tunnel approximately 1.5 metres in diameter) connecting two levels 25.5 metres apart. Composite assays up to 11.2 grams per tonne gold (g/t Au) and 179 grams per tonne silver (g/t Ag) over 3.5 metres, 15.55 g/t Au and 222 g/t Ag over 1.1 metres, and 11.93 g/t Au and 190 g/t Ag over 1.4 metres (see table 1) were obtained, with individual assays up to 27.6 g/t Au and 366 g/t Ag over 0.6 metre. The weighted average of mineralized composites within the raise assayed 6.43 g/t Au and 110 g/t Ag. "As at the historic Pinos Cuates mine (see news releases for June 2 and July 22, 2025), the existing underground workings at Dos de Mayo are giving us an important understanding of the nature of the gold-silver mineralization at El Potrero," stated Robert Archer, Pinnacle's president and chief executive officer. "What we are seeing is consistent with these low-sulphidation epithermal systems, where pockets of high-grade mineralization (called clavos in Mexico) occur within a defined horizon, likely consistent with the boiling zone of the hydrothermal fluids. At both mines, the main level appears to have been the haulage level as they are mostly unmineralized, although sporadic higher-grade assays were received. Despite the lack of historic production records, it seems likely that the haulage levels were constructed below, and outside of, the mineralized horizon. "It is important to note that sample lengths do not represent the width of the vein or the extent of the mineralization. They are simply the composite lengths of the individual channels sampled end to end and may be taken at any angle to the trend of mineralization, depending upon what is exposed underground. While the systematic and close-spaced nature of the sampling does give a representative characterization of the mineralization, the full extent of this particular clavo, as at Pinos Cuates, is as yet unknown and will require drilling to determine. "On a larger scale, the underground sampling is providing crucial information to better understand the distribution of gold and silver mineralization such that we can correlate with the surface sampling within the collective 500-metre strike length of the historic mines and then extrapolate along the entire 1,600-metre strike length that we have defined to date. We are currently in the planning stages for an underground drilling program at all three main mines that will effectively be delineation drilling on a fairly detailed scale. Further information on that will be released in due course." Of the 53 channel samples taken in the raise, grades ranged from 0.061 to 27.6 g/t Au and eight to 366 g/t Ag. An additional 146 channel samples were taken on the main level at Dos de Mayo and, as noted above, values were mostly less than one g/t Au as this is considered to be outside of the mineralized horizon. On a sublevel, approximately 25.5 metres above, and connected to, the main level, 42 channel samples were taken, in nine composites, highlighted by 10.99 g/t Au and 61 g/t Ag over 0.9 metre, and 4.22 g/t Au and 40 g/t Ag over 0.6 metre. It is not yet fully understood how the sublevel is positioned relative to the mineralized zone. All samples were assayed for gold and silver, and a suite of 32 other elements, including copper, lead and zinc. However, the base metal assays were consistently low, confirming that this is a precious metal dominant system. The Dos de Mayo mine is the southeasterly of three historical mines along a 500-metre strike length on the Dos de Mayo vein system on the Potrero property. Underground sampling is now continuing at La Dura mine to the northwest. The vein system has been traced on surface for 1,600 metres and there are other parallel and splay veins that are being further defined and evaluated as the property has never been systematically explored. The mine workings have now been accurately surveyed and individual 3-D models are being created for each mine in Leapfrog. QA/QC (quality assurance/quality control) The technical results contained in this news release have been reported in accordance with National Instrument 43-101, Standards of Disclosure for Mineral Projects. Pinnacle has implemented industry standard practices for sample preparation, security and analysis given the stage of the project. This has included common industry QA/QC procedures to monitor the quality of the assay database, including inserting certified reference material samples and blank samples into sample batches on a predetermined frequency basis. The systematic chip channel sampling was completed across exposed mineralized structures using a hammer and maul. The protocol for sample lengths established that they were not longer than two metres or shorter than 0.3 metre. The veins tend to be steeply dipping to vertical and so these samples are reasonably close to representing the true widths of the structures. Samples were collected along the structural strike or oblique to the main structural trend. All samples were bagged in prenumbered plastic bags; each bag had a numbered tag inside and were tied off with adhesive tape and then bulk bagged in rice bags in batches not to exceed 40 kilograms (kg). They were then numbered, and batch bags were tied off with plastic ties and delivered directly to the SGS laboratory facility in Durango, Mexico, for preparation and analysis. The lab is accredited to ISO/IEC 17025:2017. All samples were delivered in person by the contract geologist who conducted the sampling under the supervision of the qualified person (QP). SGS sample preparation code G_PRP89, including weight determination, crushing, drying, splitting and pulverizing, was used following industry best practices, where all samples were crushed to 75 per cent less than two millimetres (mm), riffle split off 250 grams (g), pulverized split to more than 85 per cent passing 75 microns. All samples were analyzed for gold using code GA_FAA30V5 with a fire assay determination on 30-gram (g) samples with an atomic absorption spectography finish. An ICP-OES (inductively coupled plasma optical emission spectroscopy) analysis package, including 33 elements and four-acid digestion, was performed (code GE_ICP40Q12) to determine silver (Ag), zinc (Zn), lead (Pb), copper (Cu) and other elements. Qualified person Jorge Ortega, PGeo, a qualified person and independent from Pinnacle, as defined by National Instrument 43-101, and the author of the National Instrument 43-101 technical report for the Potrero project, has reviewed, verified and approved for disclosure the technical information contained in this news release. About the Potrero property El Potrero is located in the prolific Sierra Madre Occidental of western Mexico and lies within 35 kilometres of four operating mines, including the 4,000-tonne-per-day (tpd) Cienega mine (Fresnillo), the 1,000 tpd Tahuehueto mine (Luca Mining) and the 250 tpd Topia mine (Guanajuato Silver). High-grade gold-silver mineralization occurs in a low-sulphidation epithermal breccia vein system hosted within andesites of the lower volcanic series and has three historical mines along a 500-metre strike length. The property has been in private hands for almost 40 years and has never been systematically explored by modern methods, leaving significant exploration potential. A previously operational 100 tpd plant on site can be refurbished/rebuilt and historical underground mine workings rehabilitated at relatively low cost in order to achieve near-term production once permits are in place. The property is road accessible with a power line within three kilometres. Surface rights covering the plant and mine area are privately owned (no community issues). Pinnacle will earn an initial 50-per-cent interest immediately upon commencing production. The goal would then be to generate sufficient cash flow with which to further develop the project and increase the company's ownership to 100 per cent subject to a 2-per-cent NSR (net smelter return) royalty. If successful, this approach would be less dilutive for shareholders than relying on the equity markets to finance the growth of the company. About Pinnacle Silver and Gold Corp. Pinnacle is focused on district-scale exploration for precious metals in the Americas. The high-grade Potrero gold-silver project in Mexico's Sierra Madre belt hosts an underexplored low-sulphidation epithermal vein system and provides the potential for near-term production. In the prolific Red Lake district of Northwestern Ontario, the company owns a 100-per-cent interest in the past-producing, high-grade Argosy gold mine and the adjacent North Birch project with an eight-kilometre-long target horizon. With a seasoned, highly successful management team and quality projects, Pinnacle Silver and Gold is committed to building long-term, sustainable value for shareholders.