Announcement PDF 31 Cliff Street, Fremantle WA 6160 | +61 8 6383 7883 | info@tesorogold.com.au | tesorogold.com.au ASX ANNOUNCEMENT 19 MARCH 2026 ASX: TSO OTCQB: TSORF FSE: 5D7 DISTRICT EXPLORATION ADVANCES AT EL ZORRO NEW TARGETS EMERGING ACROSS A 40KM GOLD CORRIDOR Tesoro Gold Limited (Tesoro or the Company) (ASX: TSO, OTCQB: TSORF, FSE: 5D7) is pleased to provide an update on regional exploration activities at the El Zorro Gold Project in Chile (El Zorro, or the Project). Multiple exploration campaigns, including geophysical surveys and soil sampling, have been conducted concurrently with the ongoing Ternera infill and extensional drilling programmes to define multiple high-priority drill targets across the broader El Zorro concession holding. HIGHLIGHTS • Completion of a high-resolution helicopter magnetic and radiometric survey across the entire El Zorro concession area; • Data collected outlines a >40km long, north south structural corridor, associated with gold anomalism, further extending the existing El Zorro Gold Corridor by 10km; • Multiple new intrusive bodies and structural features identified; • Newly interpreted El Zorro tonalite dyke systems highlight additional exploration potential; • Provides enhanced geophysical imaging of the existing targets across the broader El Zorro Gold Corridor; • Complementary systematic grid soil sampling completed at La Brea, Drone Hill and Pena Blanca targets; and • Soil geochemistry confirms strong gold anomalism validating the potential of multiple drill targets. Tesoro Managing Director, Zeff Reeves, commented: “El Zorro represents a rare opportunity to explore and make additional discoveries within the first Intrusive Related Gold System (IRGS) discovered in Chile and ultimately develop a district-scale gold camp. While we continue to advance and de-risk the Ternera Gold Deposit, our regional exploration programmes are rapidly expanding the pipeline of high-priority targets across the broader district. “The recently completed high resolution helicopter magnetic survey has generated excellent new datasets and has already highlighted several additional prospective intrusive centres and structural trends across the district. In parallel, systematic soil sampling at La Brea, Done Hill and Pena Blanca has further added to our initial excitement for what may be below the surface. “We remain on schedule to complete the current Ternera infill drilling programme within the next six to eight weeks, after which we expect to accelerate district-scale drilling across a number of these newly defined targets.” Tesoro Gold 2 ASX ANNOUNCEMENT 19 MARCH 2026 SURVEY DETAIL During late December 2025, New-Sense Geophysics Limited (New-Sense) were engaged to carry out a high-sensitivity, helicopter-borne magnetic and gamma-ray spectrometric geophysical survey over the entirety of the El Zorro Gold Project area, covering approximately 610km2 (see Figure 1). The survey was flown in two sectors, comprising a broad area with 200m spaced flight lines and an infill survey area flown with 100m spaced flight lines (see Figure1). A total of 4,880.50 line- kilometres were flown by helicopter to collect magnetic and radiometric data utilising a QuSpin Total-Field Magnetometer and a 1024-channel spectrometer with four downward-looking crystals (total 16 litres) and one upward-looking crystal (total 4 litres). Full details of the survey parameters are presented within the JORC tables in Appendix 1. Tesoro’s geophysical consultants, Resource Potentials Pty Ltd, carried out final data processing and imaging to produce a suite of magnetic and radiometric images that are being used for ongoing interpretation and gold targeting, in conjunction with geological and geochemical datasets. Preliminary interpretation of the helicopter magnetic and radiometric survey data has identified several structural trends that may be associated with gold mineralisation along the El Zorro Corridor, as well as multiple intrusive occurrences that remain unexplored (see Figure 1). Further processing, modelling and interpretation of the survey data is ongoing to assist target generation across the broader project area. Tesoro Gold 3 ASX ANNOUNCEMENT 19 MARCH 2026 Figure 1: El Zorro Gold Project – High-resolution geophysical survey preliminary interpretation: Magnetic susceptibility map (TMIRTP-1VDAGC). The 200m spaced flight line area is outlined in red, 100m spaced flight line area outlined in blue. The underlying image is 500m spaced regional data. Datum PSAD56 19S. Tesoro Gold 4 ASX ANNOUNCEMENT 19 MARCH 2026 SOIL SAMPLING In addition, three orientation programmes of systematic gridded soil sampling have been completed over the La Brea, Drone Hill and Pena Blanca Targets to assess this technique for defining new gold targets. These areas were selected due to the already confirmed location of surface gold mineralisation. A total of 331 samples were collected on a nominal 50m x 50m grid across areas previously identified from first-pass rock chip and channel sampling as being prospective for gold mineralisation. Samples were analysed for low level gold and 47 multi-element indicators to assist with drill targeting and identify the most gold fertile zones for follow up exploration work, including drilling. Sample details and results are presented in Appendix 2. All three targets exhibit low level gold anomalism coincident with arsenic and bismuth anomalism within the soils, a relationship commonly observed in IRGS. In addition, geochemical data has defined potassic alteration systems across each target, similar to alteration characteristics exhibited at the Ternera Gold Deposit and often associated with gold mineralisation throughout the district. Results have successfully defined geochemical anomalies at all three targets (Figures 2, 3 and 4), further enhancing their gold prospectivity. Soil geochemistry also aligns well with mapped mineralised fault zones and favourable host lithologies. The orientation soil sampling programmes validate the method to effectively identify new gold targets and alteration systems, associated with gold mineralisation at the El Zorro Gold Project. Additional soil sampling programmes are planned at multiple targets to identify new and expand existing drill targets. Tesoro Gold 5 ASX ANNOUNCEMENT 19 MARCH 2026 Figure 2: El Zorro Gold Project – La Brea Target Soil Geochemistry Map. Initial soil sampling results identify potential to expand the La Brea drill target to the northwest and south east. Refer ASX Announcement 11 December 2025 for La Brea drill results. Datum PSAD56 19S. Tesoro Gold 6 ASX ANNOUNCEMENT 19 MARCH 2026 Figure 3: El Zorro Gold Project – Drone Hill Target Soil Geochemistry Map. Initial soil sampling results identify additional potential at Drone Hill, gold in soil anomaly is coincident with previous high-grade drill results. Selected results shown, refer to ASX Announcements 23 March 2021, 13 June 2024 and 28 October 2024. Datum PSAD56 19S. Tesoro Gold 7 ASX ANNOUNCEMENT 19 MARCH 2026 Figure 4: El Zorro Gold Project – Pena Blanca Target Soil Geochemistry Map. Initial soil sampling results from the central Pena Blanca Target highlight gold potential within a large alteration zone coincident with previous high grade gold channel sampling results (refer ASX Announcement 6 November 2025) . Additional soil sampling programmes are planned to further define the Pena Blanca Target. Datum PSAD56 19S. Tesoro Gold 8 ASX ANNOUNCEMENT 19 MARCH 2026 Authorised by the Board of Tesoro Gold Ltd. For more information: Company: Zeff Reeves, Managing Director Tesoro Gold Limited info@tesorogold.com.au Table 2: Ternera Mineral Estimates for selected cut-off grades. Highlighted open pit Mineral Resource has been constrained by an optimised pit shell using a gold price of US$3000/oz and process recovery of 94.5%. The estimates in this table are rounded to reflect their precision; rounding errors are apparent. Tenera Updated MRE Indicated Inferred Total Au g/t cut-off Mt Au g/t Koz Mt Au g/t Koz Mt Au g/t Koz Optimised Open Pit at 0.30 31.8 1.10 1,123 19.5 1.11 692 51.2 1.1 1,816 2.00 3.5 3.55 394 2.5 3.54 280 5.9 3.54 673 1.00 10.5 2.08 705 7.9 2.04 520 18.5 2.06 1,225 0.70 17.5 1.58 891 13 1.57 657 30.5 1.58 1,547 0.30 31.8 1.10 1,128 26.1 1.03 863 58.1 1.07 1,992 0.20 33.8 1.05 1,144 28.7 0.96 885 62.5 1.01 2,028 Refer ASX announcement dated 4 August 2025 Tesoro Gold 9 ASX ANNOUNCEMENT 19 MARCH 2026 About Tesoro Tesoro Gold Limited has discovered and defined the first Intrusive Related Gold System in Chile. The 1.82M oz Ternera discovery is in the Coastal Cordillera region of Chile. The Coastal Cordillera region is host to multiple world-class copper and gold mines, has well established infrastructure, service providers and an experienced mining workforce. Large areas of the Coastal Cordillera remain unexplored due to the unconsolidated nature of mining concession ownership, but Tesoro, via its in-country network and experience has been able secure rights to the district- scale El Zorro gold project in-line with the Company’s strategy. Tesoro’s 95% owned Chilean subsidiary owns 95.4% of the El Zorro Gold Project (see ASX announcement released 12 August 2025). Future Performance This announcement may contain certain forward-looking statements and opinions. Forward-looking statements, including projections, forecasts and estimates, are provided as a general guide only and should not be relied on as an indication or guarantee of future performance and involve known and unknown risks, uncertainties, assumptions, contingencies and other important factors, many of which are outside the control of the Company and which are subject to change without notice and could cause the actual results, performance or achievements of the Company to be materially different from the future results, performance or achievements expressed or implied by such statements. Past performance is not necessarily a guide to future performance, and no representation or warranty is made as to the likelihood of achievement or reasonableness of any forward-looking statements or other forecast. Nothing contained in this announcement, nor any information made available to you is, or and shall be relied upon as, a promise, representation, warranty or guarantee as to the past, present or the future performance of Tesoro Gold. Competent Persons Statements The information in this report that relates to Mineral Resources is based on information compiled by Mr Lynn Widenbar (B.Sc. (Hons) Geology, M.Sc. FAusIMM, MAIG), a Competent Person who is a Fellow of The Australasian Institute of Mining and Metallurgy. Mr Widenbar is acting as an independent consultant to Tesoro Gold Limited. Mr Widenbar has sufficient experience that is relevant to the style of mineralisation and type of deposit under consideration, and to the activity being undertaken to qualify as a Competent Person as defined in the 2012 Edition of the ‘Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves’. The Company confirms that it is not aware of any new information or data that materially affects the information contained the form and context in which the Competent Person’s findings are presented have not been materially modified from in the original announcement on 4 August 2025, and all material assumptions and technical parameters underpinning the estimates in that announcement continue to apply and have not materially changed. The information in this report that relates to Exploration Results is based on information compiled by Mr Zeffron Reeves (B App Sc (Hons) Applied Geology) MBA, MAIG). Mr Reeves is a member of the Australian Institute of Geoscientists and a Director and shareholder of the Company. Mr Reeves has sufficient experience that is relevant to the style of mineralisation and type of deposit under consideration and to the activity which he is undertaking to qualify as a Competent Person as defined in the 2012 Edition of the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves. Mr Reeves consents to the inclusion in this report of the matters based on this information in the form and context in which it appears. The information in this report that relates to Geophysical Results is based on information compiled by Dr Alexander Costall. Dr Costall is a Member of the Australian Institute of Geoscientists (AIG) and the Australian Society of Exploration Geophysics (ASEG). Dr Costall is a consultant to Tesoro Gold Limited. Dr Costall has sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activity which he is undertaking to qualify as a Competent Person as defined in the 2012 Edition of the Australasian Code for Reporting of Exploration Results, Mineral Resources & Ore Reserves. The Company confirms that it is not aware of any new information or data that materially affects the historical geophysical results included in the original reports. Tesoro Gold 10 ASX ANNOUNCEMENT 19 MARCH 2026 APPENDIX 1: JORC TABLES Section 1: Sampling Techniques and Data Criteria JORC Code explanation Commentary Sampling techniques • Nature and quality of sampling (e.g. cut channels, random chips, or specific specialised industry standard measurement tools appropriate to the minerals under investigation, such as downhole gamma sondes, or handheld XRF instruments, etc.). These examples should not be taken as limiting the broad meaning of sampling. Tesoro completed soil sampling. Sampling processes are considered appropriate for the style of mineralisation and stage of work at each target. • Include reference to measures taken to ensure sample representivity and the appropriate calibration of any measurement tools or systems used. Tesoro completed soil sampling, Sampling processes are considered appropriate for the style of mineralisation. • Aspects of the determination of mineralisation that are Material to the Public Report. In cases where ‘industry standard’ work has been done, this would be relatively simple (e.g. ‘reverse circulation drilling was used to obtain 1 m samples from which 3 kg was pulverised to produce a 30 g charge for fire assay’). In other cases, more explanation may be required, such as where there is coarse gold that has inherent sampling problems. Unusual commodities or mineralisation types (e.g. submarine nodules) may warrant disclosure of detailed information. Tesoro has completed a soil sampling program. Sampling was by industry standard technique including: • location of the station using handheld GPS. • 2 kg of minus 75 micron Stream and ridge sediment samples were collected at pre determined locations. • Samples are packed in plastic bags with assay-number tickets stapled to the bag. Drilling techniques • Drill type (e.g. core, reverse circulation, open-hole hammer, rotary air blast, auger, Bangka, sonic, etc.) and details (e.g. core diameter, triple or standard tube, depth of diamond tails, face- sampling bit or other type, whether core is oriented and if so, by what method, etc.). No drilling reported in this report. Drill sample recovery • Method of recording and assessing core and chip sample recoveries and results assessed. No drilling reported in this report. • Measures taken to maximise sample recovery and ensure representative nature of the samples. No drilling reported in this report. • Whether a relationship exists between sample recovery and grade and whether sample bias may have occurred due to preferential loss/gain of fine/coarse material. No drilling reported in this report. Logging • Whether core and chip samples have been geologically and geotechnically logged to a level of detail to support appropriate Mineral Resource estimation, mining studies and metallurgical studies. Qualitative logging and descriptions of each sample were made, recorded by Tesoro’s geologists • Whether logging is qualitative or quantitative in nature. Core (or costean, channel, etc.) photography. Logging of samples was qualitative. • The total length and percentage of the relevant intersections logged. All samples logged and recorded. Tesoro Gold 11 ASX ANNOUNCEMENT 19 MARCH 2026 Criteria JORC Code explanation Commentary Subsampling techniques and sample preparation • If core, whether cut or sawn and whether quarter, half or all core taken. No drilling reported in this report • If non-core, whether riffled, tube sampled, rotary split, etc. and whether sampled wet or dry. Tesoro has not completed any percussion drilling. • For all sample types, the nature, quality and appropriateness of the sample preparation technique. Samples were pulverised to 75% passing 200 mesh in prior to digestion for assay and analysis. • Quality control procedures adopted for all subsampling stages to maximise representivity of samples. Samples were logged by a qualified geoscientist. Each subsample is considered to be representative of the sample. • Measures taken to ensure that the sampling is representative of the in-situ material collected, including for instance results for field duplicate/second-half sampling. There are field duplicate samples collected from the channels with irregular results. • Whether sample sizes are appropriate to the grain size of the material being sampled. Sample sizes collected were considered appropriate to reasonably represent the material being tested. Quality of assay data and laboratory tests • The nature, quality and appropriateness of the assaying and laboratory procedures used and whether the technique is considered partial or total. Assays reported in this report were undertaken at the accredited laboratory of ALS Santiago, which is fully certified. Sediment samples were assayed using a 25 g charge aqua regia digest and AAS finish for gold. Multielement assays were completed by 4-acid digest with a 2.5 g charge. All techniques are appropriate for the element being determined. • For geophysical tools, spectrometers, handheld XRF instruments, etc., the parameters used in determining the analysis including instrument make and model, reading times, calibrations factors applied and their derivation, etc. Specifications of the geophysical methods reproted are: Magnetic survey data measured using a QFTM total field magnetometer sampling at 250 Hz and down- sampled during post-processing to 10 Hz. Calibration of the magnetic field sensor was carried out during a specific calibration flight including a Figure of Merit to compensate for the proximity of the aircraft to the sensor. Post-processing includes diurnal, heading, lag, IGRF, tie-line levelling and reduction to pole corrections. Radiometric survey data measured using a RS-500 16L crystal pack sampling at 1 s intervals. Calibration of the RS-500 was completed by the manufacturer, with cosmic flight tests and height attention tests completed on-site. • Nature of quality control procedures adopted (e.g. standards, blanks, duplicates, external laboratory checks) and whether acceptable levels of accuracy (i.e. lack of bias) and precision have been established. QAQC procedures included the insertion of Certified Reference Materials (CRMs) (5%) and blank material (2%), Check samples (5%) and check assaying (5%) Cube Consulting Pty Ltd manage the database for Tesoro. The laboratories used have generally demonstrated analytical accuracy at an acceptable level within 95% confidence limits. Verification of sampling and assaying • The verification of significant intersections by either independent or alternative company personnel. No significant intersections have been reported. • The use of twinned holes. No twinned holes have been completed. • Documentation of primary data, data entry procedures, data verification, data storage (physical and electronic) protocols. Tesoro sampling is digitally entered and stored following documented handling protocols. The protocols are considered adequate. Tesoro Gold 12 ASX ANNOUNCEMENT 19 MARCH 2026 Criteria JORC Code explanation Commentary • Discuss any adjustment to assay data. No adjustments were made to assay data Location of data points • Accuracy and quality of surveys used to locate drillholes (collar and downhole surveys), trenches, mine workings and other locations used in Mineral Resource estimation. Sample locations have been located using a handheld GPS. Helicopter magnetic and radiometric data are GPS- located using a Novatel OEM628 GPS. • Specification of the grid system used. The grid system used PSAD56 19S • Quality and adequacy of topographic control. The topography generated from an accurate topographic survey data completed by a registered surveyor and has been used for the current control. Data spacing and distribution • Data spacing for reporting of Exploration Results. The sample is collected on a nominal 2kg of material from predetermined locations. this spacing is deemed acceptable for the style of mineralisation. • Whether the data spacing and distribution is sufficient to establish the degree of geological and grade continuity appropriate for the Mineral Resource and Ore Reserve estimation procedure(s) and classifications applied. No estimation procedures have been applied. Magnetic samples were measured every 3.5 m on average and radiometric samples were measured every 35 m on average, depending on the flying speed of the helicopter. The helicopter maintained an average altimeter elevation of 79.8 m with variation between 10 m and 274 m depending on topography • Whether sample compositing has been applied. Sample compositing was not employed at the sampling stage. Orientation of data in relation to geological structure • Whether the orientation of sampling achieves unbiased sampling of possible structures and the extent to which this is known, considering the deposit type. Samples were collected from pre determined location on a regular 50m x 50m grid. • If the relationship between the drilling orientation and the orientation of key mineralised structures is considered to have introduced a sampling bias, this should be assessed and reported if material. No drilling reported in this report. Sample security • The measures taken to ensure sample security. Chain of Custody of digital data is managed by the Company. Physical material was stored on site and, when necessary, delivered to the assay laboratory. Thereafter laboratory samples were controlled by the nominated laboratory which to date has been Bureau Veritas and ALS Santiago. All sample collection was controlled by digital sample control file(s) and hardcopy ticket books. Audits or reviews • The results of any audits or reviews of sampling techniques and data. No audits have been undertaken. Section 2: Reporting of Exploration Results Criteria JORC Code explanation Commentary Mineral tenement and land tenure status • Type, reference name/number, location and ownership including agreements or material issues with third parties such as joint ventures, partnerships, overriding royalties, native title interests, historical sites, wilderness or national park and environmental settings. Information regarding tenure is included in the Company’s December 2025 quarterly report released to the ASX on 27 January 2026. Tesoro Resources Ltd, 95% owned Chilean subsidiary, Tesoro Mining Chile SpA, owns 95.4% of the El Zorro Gold Project Concessions. • The security of the tenure held at the time of reporting along with any known impediments to obtaining a licence to operate in the area. The Concession is believed to be in good standing with the governing authority and there is no known impediment to operating in the area. Tesoro Gold 13 ASX ANNOUNCEMENT 19 MARCH 2026 Criteria JORC Code explanation Commentary Exploration done by other parties • Acknowledgment and appraisal of exploration by other parties. Little historical exploration has been undertaken in either project area. Coeur d’Alene’s Chilean exploration division undertook activities on the Ternera prospect, under an option agreement with the previous owners between April 1990 and January 1993. Geology • Deposit type, geological setting and style of mineralisation. The mineralisation model is considered to be an intrusive related gold deposit. The key characteristics that are consistent with this style deposit include: • Low sulphide content, (typically <5%); reduced ore mineral assemblage that typically comprises pyrite and lacks primary magnetite or hematite • Mineralisation occurs as sheeted vein deposits or stockwork assemblages and often combine gold with variably elevated Bi, W, As, Mo, Te, and/or Sb but low concentrations of base metals as seen in the initial four holes by Tesoro at El Zorro • Restricted and commonly weak proximal hydrothermal alteration • Intrusions of intermediate to felsic composition. Drillhole information • A summary of all information material to the understanding of the exploration results including a tabulation of the following information for all Material drillholes: o easting and northing of the drillhole collar o elevation or RL (Reduced Level – elevation above sea level in metres) of the drillhole collar o dip and azimuth of the hole o downhole length and interception depth o hole length. • If the exclusion of this information is justified on the basis that the information is not Material and this exclusion does not detract from the understanding of the report, the Competent Person should clearly explain why this is the case. All material information is presented in the report. Data aggregation methods • In reporting Exploration Results, weighting averaging techniques, maximum and/or minimum grade truncations (e.g. cutting of high grades) and cut-off grades are usually Material and should be stated. No cutting of grades has been undertaken at this early stage of exploration drilling. Downhole intercepts are calculated using a length weighted averaging method • Where aggregate intercepts incorporate short lengths of high grade results and longer lengths of low grade results, the procedure used for such aggregation should be stated and some typical examples of such aggregations should be shown in detail. Down hole length weighted average results are calculated using a 0.20g/t Au cut off and a maximum of 5m internal dilution. • The assumptions used for any reporting of metal equivalent values should be clearly stated. No metal equivalents are reported. Relationship between mineralisation • These relationships are particularly important in the reporting of Exploration Results. Tesoro Gold 14 ASX ANNOUNCEMENT 19 MARCH 2026 Criteria JORC Code explanation Commentary widths and intercept lengths • If the geometry of the mineralisation with respect to the drillhole angle is known, its nature should be reported. The mineralisation forms sub-vertical sheeted veins and individual veins and may form plunging zones within the mineralised structures. Drilling by Tesoro has been undertaken to test these orientations. • If it is not known and only the downhole lengths are reported, there should be a clear statement to this effect (e.g. ‘downhole length, true width not known’). Diagrams • Appropriate maps and sections (with scales) and tabulations of intercepts should be included for any significant discovery being reported These should include, but not be limited to a plan view of drillhole collar locations and appropriate sectional views. Relevant maps and diagrams are included in the body of the report. Balanced reporting • Where comprehensive reporting of all Exploration Results is not practicable, representative reporting of both low and high grades and/or widths should be practiced to avoid misleading reporting of Exploration Results. All material assay results from drilling are reported. Other substantive exploration data • Other exploration data, if meaningful and material, should be reported including (but not limited to): geological observations; geophysical survey results; geochemical survey results; bulk samples – size and method of treatment; metallurgical test results; bulk density, groundwater, geotechnical and rock characteristics; potential deleterious or contaminating substances. All material exploration data is reported in the body of the report. Further work • The nature and scale of planned further work (e.g. tests for lateral extensions or depth extensions or large-scale step-out drilling). Further work will be focused on drill testing the Ternera mineralisation and additional prospects as defined in the work program. Core will be used for metallurgical testwork and further resource modelling is planned. • Diagrams clearly highlighting the areas of possible extensions, including the main geological interpretations and future drilling areas, provided this information is not commercially sensitive. Diagrams have been included in the body of this report. Tesoro Gold 15 ASX ANNOUNCEMENT 19 MARCH 2026 APPENDIX 2: GEOCHEMISTRY TABLES Tesoro Gold 16 ASX ANNOUNCEMENT 19 MARCH 2026 Tesoro Gold 17 ASX ANNOUNCEMENT 19 MARCH 2026 Tesoro Gold 18 ASX ANNOUNCEMENT 19 MARCH 2026 Tesoro Gold 19 ASX ANNOUNCEMENT 19 MARCH 2026 Tesoro Gold 20 ASX ANNOUNCEMENT 19 MARCH 2026 Tesoro Gold 21 ASX ANNOUNCEMENT 19 MARCH 2026 Tesoro Gold 22 ASX ANNOUNCEMENT 19 MARCH 2026 Tesoro Gold 23 ASX ANNOUNCEMENT 19 MARCH 2026 Tesoro Gold 24 ASX ANNOUNCEMENT 19 MARCH 2026