Meridian Announces the Discovery of Gold Mineralisation at Álamo and Reports Further High-Grade Results from Santa Helena Central

Highlights:

• Meridian's exploration programme discovers new high-grade gold at Álamo:
  • CD-852 returns 3.5m @ 2.4g/t Au, 0.5% Cu, 9.5g/t Ag & 0.7% Zn from 108.9m;
  • Peak gold assay of 8.8 g/t Au over 0.4m, with robust gold grades over multiple metres;
    • Structurally hosted gold mineralisation that remains open in all directions
    • Located on the western sector of the 1.6km Álamo trend;
• Infill drill programme at Santa Helena Central returns near-surface high-grade results:
  • CD-854: 21.2m @ 1.5g/t Au, 1.2% Cu, 45.7g/t Ag & 6.0% Zn from 71.6m;
    • Incl. 10.7m @ 2.5g/t Au, 2.4% Cu, 76.7g/t Ag & 11.7% Zn from 73.0m;
  • CD-853: 14.8m @ 1.5g/t Au, 1.6% Cu, 41.9g/t Ag & 5.8% Zn from 29.7m;
    • Incl. 6.9m @ 2.8g/t Au, 3.2% Cu, 78.0g/t Ag & 10.3% Zn from 32.8m;
  • CD-849: 11.7m @ 2.2g/t Au, 1.8% Cu, 50.3g/t Ag & 3.9% Zn from 46.4m;
    • Incl. 5.3m @ 4.5g/t Au, 3.9% Cu, 103.7g/t Ag & 7.7% Zn from 47.4m; and
  • Peak grades of 17.5 g/t Au (CD-840, 26.5 - 27.2m), 311g/t Ag (CD-847: 79.8 - 80.4m), 11.6% Cu (CD-833, 32.4 - 33.2m) and 22.1% Zn (79.8 - 80.4m) are among the highest ever recorded at Santa Helena Central.

London, May 14, 2026 - Meridian Mining Plc (LSE: MNO) (TSX: MNO) (FSE: N2E0) (Tradegate: N2E0) (OTCQX: MRRDF) ("Meridian" or the "Company") is pleased to announce the discovery of gold and base metal mineralisation at Álamo ("Álamo"), located at the southeastern end of the Cabaçal Au-Cu-Ag VMS belt ("Cabaçal") and only 1km from Santa Helena's infrastructure area (Figure 1). The exploration discovery hole, CD-852, intersected 3.5m @ 2.4g/t Au, 0.5% Cu, 9.5g/t Ag & 0.7% Zn from 108.9m. It represents a newly defined mineralised position, open along strike, up-dip and down-dip, along a 1.6km Induced Polarisation ("IP") anomaly.

The Company also reports results from Santa Helena Central's resource infill programme (Figure 1). The high-grade zones of gold-copper-silver and lead-zinc include CD-854's high-grade core of 10.7m @ 2.5g/t Au, 2.4% Cu, 76.7g/t Ag & 11.7% Zn from 73.0m. These results will be included in a future resource upgrade.

Mr. Gilbert Clark, CEO, comments: "The discovery of gold at Álamo is a tremendous result from one of our many exploration targets. The discovery hole, CD-852, is located on the western sector of the Álamo prospect and structurally overprints the mine sequence stratigraphy. The development of gold-dominant intersections is an element we see at the Cabaçal deposit to the northwest. If Álamo's success continues, it can only strengthen the potential of realising a second operational hub at the adjacent deposit of Santa Helena Central".

Álamo Gold Discovery

The Álamo trend represents a 1.6km eastern trend that connects to the west with the larger Santa Helena system. Hydrothermal processes are reflected by geophysical response with a positive chargeability anomaly (consistent with bedrock sulphides), and peak soil responses from past historical sampling of 820 ppm Cu, 1300 ppm Zn, 3040 ppm Pb, and up to 90 gold counts (gold specks in panned 5 litre soil sample).

CD-852's discovery represents a return to the evaluation of the opportunities that the Álamo trend presents, with recent drilling purposefully directed into the Santa Helena system's footwall position. In this underlying position below and to the east of the Santa Helena Central resource, historical drilling (JUCHD018, JUCHD014, JUCHD021) intercepted mineralisation, that although at low levels, signalled that a fertile hydrothermal system was present in the poorly tested lower position.

CD-852 was collared 240m from the limit of the Santa Helena Central resource model extent, and ~230m east of the mineralised position of the historical JUCHD021, that assayed trace level gold grades in the Santa Helena footwall position. CD-852 passed through an interlayered sequence of mafic and felsic meta-volcanics, and encountered multiple horizons with anomalous gold, base metal and/or pathfinder signatures. Gold-only zones were first encountered at 48.0 - 48.3m and 62.3 - 63.1m. A zinc-lead interval from 88.1 - 93.6m with higher Ba/Zr ratios and adjacent elevated Mo-Cd may mark an exhalative position. Importantly, the interval from 108.9 - 112.4m returned strong gold-silver mineralisation, with an intersection of 3.5m @ 2.4g/t Au, 0.5% Cu, 9.5g/t Ag & 0.7% Zn from 108.9m (Table 1; Figure 2). The peak gold grade reported was 8.8g/t Au over 0.4m from 110.8m. This is the highest gold grade encountered to date in the limited drill-testing of the Santa Helena footwall position. The interval has elevated base metals, but is overall a low-sulphur zone, with gold grades higher than those characteristic of the VMS-only event. The interval occurs in a zone of Na-depletion characteristic of hydrothermal leaching and is accompanied by an elevated pathfinder signal (Bi-Mo-Se-Cd). The mineralised interval is interpreted to dip moderately to the southwest and remains open.

Previously CD-431, drilled north of CD-852, returned 5.4m @ 0.4g/t Au, 27.8 g/t Ag, 0.4% Zn from 38.4m, in a shallow northerly dipping package. BHEM surveys of CD-431 and CD-432 (NSA) identified a modelled conductor extending over 40m+ along strike, that is the strongest BHEM response detected to date at Santa Helena, with a high conductivity of ~4200 Siemens. This will be tested as part of Álamo's ongoing 2026 exploration programme.

Table 1: CD-852 Álamo gold zone assay results.

Figure 1: Location of CD-852 drill collar on the 1.6km Álamo trend.

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Figure 2: CD-852 mineralised drill core with gold grades annotated in grams/tonne.

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Whilst projecting up-dip towards the off-section CD-431 mineralisation previously reported, the two positions are not exactly co-planar, and are interpreted to have different dips and have slightly different geological associations. Further drilling is being conducted to test for mineralisation between the shallow-dipping mafic sills. CD-852 is the most easterly hole drilled in the current campaign to date, with ongoing drilling testing for mineralisation both along the principal Induced Polarisation chargeability corridor and associated with the satellite Santa Helena north anomaly.

The CD-852 results provide another example of an elevated bismuth pathfinder signal seen in association with the high-grade gold event in mineralisation of the Cabaçal Belt. This geochemistry is seen in camps such as La Ronde - Penna, which like the Cabaçal Belt, has a subvolcanic tonalite intrusive body contributing to the metal associations. In the La Ronde - Penna camp, the mineralisation can be stacked at different intervals. The Company has previously noted that, with the Cabaçal Belt being characterised by gentle dips, there is a significant footprint of unexplored stratigraphy between this sub-volcanic intrusive tonalite system and the known VMS horizon to date. With the CD-852 result, we are now increasingly confident in the opportunity for drilling to encounter blind positions, and we look forward to testing for extensions or repeats of the mineralisation.

Additional holes drilled in the broader region (Figure 1), include CD-762, CD-767 and CD-825. CD-762 was the first hole into the Santa Helena Far North chargeability response. The hole intersected a weathered mafic - metasediment interval in the weathering zone which was anomalous in gold, bismuth and other pathfinders (47 ppb Au; 5 ppm Bi, 356 ppm As). Assays indicated a second meta-volcanic / meta-sediment contact at 77.7m depth was associated with a sodium depletion zone in which the hole terminated at 85.1m. Results indicate the chargeability response is associated with dynamic hydrothermal processes with further work required to build exploration vectors. CD-762 was a first hole into an area which had returned anomalous gold in rock chip float. The hole returned grades of up to 0.4% Cu and the area is under further evaluation. Hole CD-825 was drilled to the south and returned low levels of Cu-Au anomalism.

Resource Development - Santa Helena Central

Further drilling has been undertaken at Santa Helena Central (Figure 3). Recent drilling has included holes targeting unmined zones of the historical workings, to increase the data population for comparison with historical grade control, whilst at the same time providing further validation to the void model.

Recent results have included:

• CD-854: 21.2m @ 1.5g/t Au, 1.2% Cu, 45.7g/t Ag & 6.0% Zn from 71.6m;
  • Incl. 10.7m @ 2.5g/t Au, 2.4% Cu, 76.7g/t Ag & 11.7% Zn from 73.0m;
• CD-853: 14.8m @ 1.5g/t Au, 1.6% Cu, 41.9g/t Ag & 5.8% Zn from 29.7m;
  • Incl. 6.9m @ 2.8g/t Au, 3.2% Cu, 78.0g/t Ag & 10.3% Zn from 32.8m;
• CD-849: 11.7m @ 2.2g/t Au, 1.8% Cu, 50.3g/t Ag & 3.9% Zn from 46.4m;
  • Incl. 5.3m @ 4.5g/t Au, 3.9% Cu, 103.7g/t Ag & 7.7% Zn from 47.4m;
• CD-847: 20.2m @ 0.9g/t Au, 1.3% Cu, 49.3g/t Ag & 9.7% Zn from 54.2m;
  • Incl. 12.3m @ 1.2g/t Au, 1.8% Cu, 70.5g/t Ag & 13.3% Zn from 59.8m;
• CD-855: 22.0m @ 0.6g/t Au, 0.6% Cu, 25.8g/t Ag & 2.6% Zn from 31.0m;
  • Incl. 14.8m @ 0.8g/t Au, 0.8% Cu, 37.5g/t Ag & 3.7% Zn from 34.7m;
• CD-845: 13.5m @ 1.1g/t Au, 1.0% Cu, 48.9g/t Ag & 6.4% Zn from 77.5m;
  • Incl. 9.9m @ 1.4g/t Au, 1.3% Cu, 64.8g/t Ag & 8.6% Zn from 77.8m;
• CD-840: 13.2m @ 1.3g/t Au, 0.3% Cu, 22.9g/t Ag & 1.2% Zn from 21.0m;
  • Incl. 2.1m @ 7.8g/t Au, 1.1% Cu, 120.4g/t Ag & 5.8% Zn from 25.6m.

Figure 3: Santa Helena Central - recent highlights.

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Several holes terminated in voids (CD-858, CD-866, CD-849). Further results are pending and will be used to update the statistical comparison with grade control data. Peak grades encountered from the recent programme include 17.5 g/t Au (CD-840, 26.5 - 27.2m), 311g/t Ag (CD-847: 79.8 - 80.4m), 11.6% Cu (CD-833, 32.4 - 33.2m), and 22.1% Zn (CD-847, 79.8 - 80.4m). This compares to peak historical grade control data values of 16.2g/t Au (CAN-109, 0.0 - 1.1m), 210 g/t Ag (CAN-109: 0.0 - 1.1m), 7.7% Cu (FP-31: 0 - 1.5m), 32.8% Zn (M-63: 0.0 - 1.0m).

The Company will also be assessing the potential to increase gold recovery in the primary zone through further metallurgical studies at SGS Lakefield, with a programme to be initiated shortly, and continues to engage with the state environmental agency, SEMA, for environmental licensing of the Santa Helena region.

Technical Notes

Drill core samples have been analysed at ALS laboratory in Lima, Peru. Samples are dried, crushed with 70% passing 85% passing 200µm. Routine gold analyses have been conducted by Au‐AA24 (fire assay of a 50g charge with AAS finish). High‐grade samples (>10g/t Au) are repeated with a gravimetric finish (Au‐GRA22), and base metal analysis by methods ME-ICP61 and OG62 (four acid digest with ICP-AES finish). Visible gold intervals are sampled by metallic screen fire assay method Au‐SCR21. Samples are held in the Company's secure facilities until dispatched and delivered by staff and commercial couriers to the laboratory. Pulps and coarse rejects are retained and returned to the Company for storage. The Company submits a range of quality control samples, including blanks and gold and polymetallic standards supplied by Rocklabs, ITAK and OREAS, supplementing laboratory quality control procedures. Approximately 5% of archived samples are sent for umpire laboratory analysis, including any lots exhibiting QAQC outliers after discussion with the laboratory. In BP Minerals sampling, gold was analysed historically by fire assay and base metals by three acid digest and ICP finish at the Nomos laboratory in Rio de Janeiro. Silver was analysed by aqua regia digest with an atomic absorption finish. True width is considered to be 85-95% of intersection width. Assay figures and intervals are rounded to 1 decimal place.

Induced polarization surveys have been conducted by the Company's in-house team utilizing its GDD GRx8-16c receiver and 5000W-2400-15A transmitter. Results are sent daily for processing and quality control to the Company's consultancy, Core Geophysics. Geophysical and geochemical exploration targets are preliminary in nature and not conclusive evidence of the likelihood of a mineral deposit.

Qualified Person Statement

Mr. Erich Marques, B.Sc., FAIG, Chief Geologist of Meridian Mining and a Qualified Person as defined by National Instrument 43-101, has reviewed, verified and approved the technical information in this news release.

About Meridian

Meridian Mining is focused on:

• The development and exploration of the advanced stage Cabaçal VMS gold‐copper project;

• Expanding the initial resource inventory at in the Santa Helena area through extension of Santa Helena Central, and new discoveries;

• Regional scale exploration of the Cabaçal VMS Belt to expand the Cabaçal Hub strategy; and

• Exploration in the Jauru & Araputanga Greenstone Belts (the above all located in the State of Mato Grosso, Brazil).

The Pre-feasibility Study technical report (the "PFS Technical Report") dated March 31, 2025, entitled: "Cabaçal Gold-Copper Project NI 43-101 Technical Report and Pre-feasibility Study" outlines a base case after-tax NPV5 of USD 984 million and 61.2% IRR from a pre-production capital cost of USD 248 million, leading to capital repayment in 17 months (assuming metals price scenario of USD 2,119 per ounces of gold, USD 4.16 per pound of copper, and USD 26.89 per ounce of silver). Cabaçal has a low All-in-Sustaining-Cost of USD 742 per ounce gold equivalent & production profile of 141,000-ounce gold equivalent life of mine, driven by high metallurgical recovery, a low life-of-mine strip ratio of 2.3:1, and the low operating cost environment of Brazil.

The Cabaçal Mineral Reserve estimate consists of Proven and Probable reserves of 41.7 million tonnes at 0.63g/t gold, 0.44% copper and 1.64g/t silver (at a 0.25 g/t gold equivalent cut-off grade).

Readers are encouraged to read the PFS Technical Report in its entirety. The PFS Technical Report may be found under the Company's profile on SEDAR+ at www.sedarplus.ca and on the Company's website at www.meridianmining.co.

The PFS Technical Report was prepared for the Company by Tommaso Roberto Raponi (P. Eng), Principal Metallurgist with Ausenco Engineering Canada ULC; Scott Elfen (P. E.), Global Lead Geotechnical and Civil Services with Ausenco Engineering Canada ULC; John Anthony McCartney, C.Geol., Ausenco Chile Ltda.; Porfirio Cabaleiro Rodriguez (Engineer Geologist FAIG), of GE21 Consultoria Mineral; Leonardo Soares (BSc Geo, MAIG), Senior Geological Consultant of GE21 Consultoria Mineral; Norman Lotter (Mineral Processing Engineer; P.Eng.), of Flowsheets Metallurgical Consulting Inc.; and, Juliano Felix de Lima (Engineer Geologist MAIG), of GE21 Consultoria Mineral.

On behalf of the Board of Directors of Meridian Mining plc

Mr. Gilbert Clark - CEO and Director

Meridian Mining plc
8th Floor, 4 More London Riverside
London SE1 2AU
United Kingdom

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Cautionary Statement on Forward-Looking Information

Some statements in this news release contain forward-looking information or forward-looking statements for the purposes of applicable securities laws. These statements address future events and conditions and so involve inherent risks and uncertainties, as disclosed under the heading "Risk Factors" in Meridian's most recent Annual Information Form filed on www.sedarplus.ca. While these factors and assumptions are considered reasonable by Meridian, in light of management's experience and perception of current conditions and expected developments, Meridian can give no assurance that such expectations will prove to be correct. Any forward-looking statement speaks only as of the date on which it is made and, except as may be required by applicable securities laws, Meridian disclaims any intent or obligation to update any forward-looking statement, whether as a result of new information, future events, or results or otherwise.

Table 1: Assay Results - Santa Helena

Table 1: Assay Results - Santa Helena Near-Mine Exploration

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