Meridian Drills Multiple Intersections of Shallow High-Grade Au-Cu-Ag & Zn Mineralization at Santa Helena

Rhea-AI Summary

Meridian Mining (MRRDF) reports significant drilling results from its Santa Helena Au-Cu-Ag & Zn project, revealing multiple shallow high-grade mineralization intersections. Key findings include CD-660 with 11.6m @ 5.9g/t AuEq from 42.0m and CD-700 with 17.6m @ 3.6g/t AuEq from 4.6m. The company achieved its highest-grade bedrock gold intersection to date at Santa Helena, with 25.4g/t Au and 449.0g/t Ag in hole CD-701. The ongoing infill drill program aims to increase confidence in mineralization geometry and grade continuity, supporting a resource estimate planned for later this year. Additionally, Meridian is expanding exploration programs at Santa Fé, located 5km south of Santa Helena, where geochemical and IP anomalies show promising results.

Positive

• Multiple high-grade intersections discovered, including highest-grade bedrock gold intersection to date of 25.4g/t Au and 449.0g/t Ag
• Shallow mineralization found across multiple drill holes, suggesting potential for open pit mining
• Successful infill drilling program strengthening confidence for upcoming resource estimate
• Expansion of exploration programs at Santa Fé showing promising geochemical and IP anomalies

Negative

• Some drill holes terminated early due to mining voids, potentially limiting full mineralization assessment
• Certain historical datasets were not fully sampled, requiring additional verification
• Some areas have colluvial cover, making exploration more challenging

Highlights:

• Meridian drills multiple intersections of shallow high-grade Au-Cu-Ag & Zn mineralization at Santa Helena:

  • CD-660: 11.6m @ 5.9g/t AuEq (4.0% CuEq) from 42.0m*;

    • Including 7.5m @ 8.0g/t AuEq (5.4% CuEq) from 44.5m;

  • CD-700: 17.6m @ 3.6g/t AuEq (2.4% CuEq) from 4.6m;

    • Including 7.8m @ 5.6g/t AuEq (3.8% CuEq) from 13.5m;

  • CD-691: 8.3m @ 3.8g/t AuEq (2.6% CuEq) from 39.5m;

    • Including 4.5m @ 6.3g/t AuEq (4.2% CuEq) from 39.5m;

  • CD-686: 8.3m @ 3.7g/t AuEq (2.5% CuEq) from 53.0m;

    • Including 4.2m @ 6.8g/t AuEq (4.6% CuEq) from 57.1m;

  • CD-701: 7.0m @ 5.2g/t AuEq (3.5% CuEq) from 42.0m;

    • Including 2.5m @ 7.3g/t AuEq (4.9% CuEq) from 46.0m;

• Meridian drills its highest-grade bedrock gold intersection to date at Santa Helena of 25.4g/t Au and 449.0g/t Ag (CD-701: CBDS103356; 48.1 - 48.45m); and

• Meridian expands multiple surface exploration programs at Santa Fé.

*See Technical note for AuEq and CuEq equations and inputs.

LONDON, UK / ACCESS Newswire / June 10, 2025 / Meridian Mining UK S (TSX:MNO),(Frankfurt/Tradegate:2MM)(OTCQX:MRRDF) ("Meridian" or the "Company") is pleased to provide an update on its Santa Helena Au-Cu-Ag & Zn project ("Santa Helena"). Multiple intersections of shallow high-grade Au-Cu-Ag & Zn mineralization have been drilled as part of Santa Helena's expanded resource delineation drill program¹.

The Company is also reporting, that due to strong extensions of geochemical and coincident geophysical anomalies at Santa Fé, it is expanding the active exploration programs there. Drill programs at Cabaçal, Santa Helena and Santa Fé continue with results pending.

Mr. Gilbert Clark, CEO, comments: "We continue to confirm more shallow and high-grade zones of Au-Cu-Ag & Zn mineralization at Santa Helena, including one of our highest grading gold assays to date. This continual stream of strong results from the on-going infill drill program are strengthening our confidence for the Santa Helena resource estimate that is planned for later this year. Having this potential for a second open pit with Santa Helena can only strengthen the optionality of it also becoming the 2^nd processing hub of the Cabaçal belt.

At only 5km to the south of Santa Helena, the scale of the exploration activity at Santa Fé is developing quickly. We are seeing an expansion of open robust geochemical and IP anomalies and have a rig active there. With multiple deposits being developed, one of the best PFS economic results² in recent time and an expanding exploration program. I am confident when I express that the Cabaçal Au-Cu belt is the preeminent VMS Au-Cu development project of South America."

¹ See Meridian news release of April 15, 2025.

² See Meridian news release of March 10, 2025.

Santa Helena Drilling

The Santa Helena infill drill program continues, delivering strong results in the eastern and western sectors of the deposit ("Figure 1" "Table 1"). Drilling is being conducted to increase confidence in the Au-Cu-Ag & Zn mineralization's geometry and grade continuity characteristics, particularly related to historical datasets where holes were not fully sampled.

CD-686, on the western sector of the deposit, returned 8.3m @ 3.7g/t AuEq (2.5% CuEq) from 53.0m, including a higher-grade core of 4.2m @ 6.8g/t AuEq (4.6% CuEq) from 57.1m. The result was wider than the partially sampled position in adjacent historical hole, PM22A, which was 6.0m @ 3.6g/t AuEq (2.4% CuEq) from 53.2m.

Along strike, CD-701 returned 7.0m @ 5.2g/t AuEq (3.5% CuEq) from 42.0m, including 2.5m @ 7.3g/t AuEq (4.9% CuEq) from 46.0m. This includes a high-grade precious metal dominant sample of 25.4g/t Au, 449g/t Ag, 3.1% Zn, 0.4% Cu (CBDS103356; 48.1 - 48.45m). With ongoing work, the Company will monitor whether there is a particular depositional or structural control on the emergence of these high-grade samples in the dataset. CD-701 is located up-dip from an access drive at the far western limit of the underground workings, which did not receive grade control diamond drilling before the closure of the mine.

Along strike to the east, CD-660 returned a 11.6m @ 5.9g/t AuEq (4.0% CuEq) from 42.0m, including 7.5m @ 8.0g/t AuEq (5.4% CuEq) from 44.5m, and including 1.3m @ 12.8g/t AuEq (8.6% CuEq) from 48.7m. The hole terminated in a dry mining void at 55.6m, unable to advance to test a possible extension of footwall mineralization.

Up-dip infill drilling on the western flank of the deposit included:

Hole-id	Zone	Int (m)	AuEq (g/t)	CuEq (%)	From (m)
CD-700	SHM
		17.6	3.6	2.4	4.6
	Including	7.8	5.6	3.8	13.5
	Including	2.7	10.5	7.1	18.1
CD-699	SHM
		8.7	3.9	2.6	24.2
	And	2.2	3.4	2.6	41.0
CD-698	SHM
		9.6	1.9	1.3	23.1
	Including	1.5	3.5	2.3	24.3
CD-697	SHM
		19.5	1.3	0.9	2.4
	Including	5.8	2.8	1.9	3.1
CD-691	SHM
		8.3	3.8	2.6	39.5
	Including	4.5	6.3	4.2	39.5
CD-685	SHM
		9.0	0.9	0.6	38.6
	Including	2.1	2.1	1.4	45.4

Results from the shallow eastern sector of the deposit included CD-674 which cut the upper projection of the sheet and its immediate footwall, returning 18.0m @ 1.9g/t AuEq (1.2% CuEq) from 2.8m, including 7.9m @ 3.3g/t AuEq (2.2% CuEq) from 2.8m and including 3.0m @ 6.0g/t AuEq (4.0% CuEq) from 3.8m. Positions targeting the footwall zones below the main sheet and included CD-670, returning 13.5m @ 0.6g/t AuEq (0.4% CuEq) from surface, and 11.3m @ 0.3g/t AuEq (0.2% CuEq) from 17.2m. CD-668 further outboard from the main sheet returned lower grade halo material.

Resource definition will be ongoing through the second half of the year. The infill will be important to the definition of the VMS sheet geometry, which can show both thickening and thinning relating to folding and strain.

Figure 1: Santa Helena drilling highlights.

Santa Fé Target

Following the reporting of a new target area, Santa Fe, in the southeast of the Cabaçal Belt, in April 2025, the Company has expanded its reconnaissance programs with an extension of the induced polarization survey to the west and an active geochemical stream and soil sampling program. Geochemical results have expanded the footprint of the soil anomaly previously reported at Santa Fé. The Company believes the Santa Fé, and Santa Helena trends have the potential to extend into Meridian's new exploration licence applications which are awaiting approval.

Geophysical and geochemical programs have also been extended eastwards through an area largely obscured by colluvial cover but with local pockets of greenstone belt exposed. Stream geochemistry is being undertaken as a first indicator of metal anomalism in areas down-cut through the colluvial sheet. The extension of the geophysical grid is showing a number of anomalies emerging in this newly expanded eastern area ("Figure 2"; "Figure 3").

The Company has mobilized a rig to start shallow reconnaissance drilling in order to characterize bedrock associated with chargeability anomalies, with results pending.

Figure 2: Newly located soil anomaly at Santa Fé, ~5km southeast of Santa Helena, marking a potential fold-repeat of the VMS stratigraphic horizon. Background image is RTP tilt-derivative magnetics.

Figure 3: Copper-in soil geochemical response over Santa Fé, superimposed on a chargeability grid. Background image is RTP tilt-derivative magnetics.

Technical Notes

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 70-90% of intersection width, except for low-angle holes CD-624, CD-643, CD-651 and CD-661 which are considered to be ~20% of true width. Assay figures and intervals are rounded to 1 decimal place.

Gold equivalents for Santa Helena are based on metallurgical recoveries from the historical resource calculation, updated with pricing forecasts aligned with the Cabaçal PEA. AuEq (g/t) = (Au(g/t) * 65%Recovery) + (1.492*Cu(%) * 89%Recovery) + (0.474*Zn% * 89%Recovery)) + (0.013*Ag(g/t) * 61%Recovery)). CuEq (%) = (Cu(%) * 89%Recovery) + (0.318*Zn% * 89%Recovery)) + (0.67*Au(g/t) * 65%Recovery) + (0.0087*Ag(g/t) * 61%Recovery)). Metallurgical testwork is currently in progress to evaluate recoveries in primary lithologies and saprolite, with formulas to be updated based on revised recoveries pricing.

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. Modelling of conductivity response is undertaken using industry-standard Maxwell software. 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;

• The initial resource definition at the second higher-grade VMS asset at Santa Helena as the first stage of the Cabaçal Hub development strategy;

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

• Exploration in the Jaurú & 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 (PGeo, 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 UK S
Mr. Gilbert Clark - CEO and Director
Meridian Mining UK S
8th Floor, 4 More London Riverside
London SE1 2AU
United Kingdom
Email: info@meridianmining.co
Ph: +1 778 715-6410 (BST))

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Further information can be found at: www.meridianmining.co

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 from Santa Helena Drilling

Hole-id	Dip	Azi	EOH	Zone	Int	AuEq	CuEq	Au	Cu	Ag	Zn	Pb	From
			(m)		(m)	(g/t)	(%)	(g/t)	(%)	(g/t)	(%)	(%)	(m)
CD-707	-78	190	59.9	SHM
					18.6	0.9	0.6	0.2	0.3	12.5	0.8	0.2	40.0
				Including	3.5	2.1	1.4	0.3	1.1	30.5	0.5	0.2	40.9
				Including	3.2	1.5	1.0	0.2	0.1	18.7	2.3	0.6	52.8
CD-701	-75	191	70.0	SHM
					0.9	1.5	1.0	2.2	0.0	0.4	0.0	0.0	38.5
					7.0	5.2	3.5	3.3	0.3	71.4	5.0	1.4	42.0
				Including	2.5	7.3	4.9	5.5	0.3	96.9	6.0	1.6	46.0
					1.1	0.8	0.6	0.7	0.1	6.4	0.5	0.1	59.4
CD-700	-86	198	45.0	SHM
					17.6	3.6	2.4	1.3	1.1	34.2	2.3	1.5	4.6
				Including	7.8	5.6	3.8	1.2	1.9	46.9	4.5	1.9	13.5
				Including	2.7	10.5	7.1	2.1	3.4	55.8	10.1	0.6	18.1
CD-699	-67	197	50.0	SHM
					8.7	3.9	2.6	0.5	0.5	26.1	6.3	1.1	24.2
				Including	1.9	8.4	5.7	1.3	1.6	55.4	12.1	1.8	25.1
				Including	1.7	6.8	4.6	0.6	0.5	43.7	12.8	2.0	29.0
					2.2	3.4	2.3	0.3	0.2	17.7	6.7	0.6	41.0
CD-698	-65	191	35.3	SHM
					9.6	1.9	1.3	0.7	0.5	9.7	1.7	0.9	23.1
				Including	1.5	3.5	2.3	2.8	0.9	19.7	0.6	2.4	24.3
CD-697	-78	186	35.1	SHM
					19.5	1.3	0.9	0.7	0.4	11.4	0.6	0.6	2.4
				Including	5.8	2.8	1.9	2.3	0.6	27.5	0.5	1.5	3.1
CD-696	-64	191	40.0	SHM
					18.6	1.0	0.7	0.5	0.2	4.5	0.8	0.2	18.4
				Including	2.9	2.3	1.5	2.7	0.2	5.2	0.5	0.4	18.4
CD-691	-50	189	60.2	SHM
					8.3	3.8	2.6	2.3	1.1	31.3	1.5	2.1	39.5
				Including	4.5	6.3	4.2	4.2	1.9	49.5	1.4	3.6	39.5
					1.9	1.5	1.0	0.1	0.1	9.0	3.0	0.8	50.5
CD-690	-89	000	45.0	SHM
					28.8	1.0	0.7	0.2	0.4	6.5	0.8	0.2	3.2
				Including	13.3	1.5	1.0	0.3	0.5	9.0	1.2	0.3	17.6
				Including	6.5	2.0	1.3	0.4	0.8	9.1	1.2	0.5	17.6
CD-688	-58	173	35.2	SHM
					17.2	0.9	0.6	0.1	0.3	4.8	0.9	0.1	4.4
				Including	1.5	3.0	2.0	0.6	1.2	9.5	2.2	0.7	9.7
CD-686	-72	187	81.3	SHM
					8.3	3.7	2.5	0.5	0.9	46.5	4.3	0.9	53.0
				Including	4.2	6.8	4.6	0.7	1.6	87.7	8.4	1.8	57.1
				Including	1.4	9.1	6.1	1.6	3.2	126.7	6.6	1.2	57.6
					3.0	0.3	0.2	0.3	0.0	15.2	0.0	0.3	74.0
CD-685	-51	189	61.1	SHM
					3.0	0.6	0.4	0.0	0.2	1.3	0.7	0.3	30.1
					9.0	0.9	0.6	0.1	0.3	3.8	1.1	0.4	38.6
				Including	2.1	2.1	1.4	0.2	0.8	3.3	2.0	1.3	45.4
CD-682	-70	193	25.0	SHM
					17.6	1.3	0.9	0.2	0.5	3.6	1.4	0.2	2.5
				Including	3.0	3.1	2.1	0.3	1.2	1.1	2.9	0.7	2.5
CD-681	-78	187	15.0	SHM
					2.6	0.6	0.4	0.6	0.1	3.8	0.1	0.2	0.0
CD-677	-88	000	105.1	SHM
					12.3	0.5	0.3	0.2	0.1	5.1	0.6	0.1	67.2
				Including	3.1	1.1	0.7	0.5	0.2	10.8	0.8	0.2	68.5
CD-676	-52	189	30.1	SHM
					16.3	0.9	0.6	0.3	0.2	9.2	0.8	0.1	2.1
CD-674	-71	215	45.5	SHM
					18.0	1.9	1.2	1.6	0.3	5.8	0.7	0.4	2.8
				Including	7.9	3.3	2.2	3.4	0.6	3.7	0.6	0.5	2.8
				Including	3.0	6.0	4.0	7.0	0.8	4.8	0.8	0.9	3.8
					0.4	2.5	1.7	3.8	0.0	0.7	0.0	0.0	25.6
CD-672	-65	207	42.0	SHM
					3.8	1.4	1.0	0.7	0.6	9.2	0.4	0.8	0.0
					24.0	0.5	0.3	0.1	0.1	3.2	0.6	0.1	5.7
CD-670	-61	206	36.1	SHM
					13.5	0.6	0.4	0.3	0.2	4.9	0.2	0.3	0.0
					11.3	0.3	0.2	0.1	0.0	7.5	0.3	0.1	17.2
					2.4	0.6	0.4	0.0	0.1	3.8	1.0	0.3	31.6
CD-668	-65	036	40.7	SHM
					3.5	0.3	0.2	0.2	0.0	6.2	0.3	0.2	7.6
					1.6	0.3	0.2	0.1	0.1	3.0	0.2	0.2	17.1
					1.0	0.9	0.6	1.0	0.0	10.7	0.5	0.3	26.0
CD-662	-64	193	47.8	SHM
					22.6	0.8	0.5	0.2	0.2	7.7	0.7	0.3	6.6
				Including	11.6	1.0	0.7	0.2	0.3	6.9	0.8	0.2	6.6
					2.8	1.0	0.6	0.1	0.2	5.7	1.6	0.2	33.9
CD-660	-44	054	55.6	SHM
					11.6	5.9	4.0	1.6	1.2	61.2	6.7	1.3	42.0
				Including	7.5	8.0	5.4	1.8	1.7	79.4	9.6	1.7	44.5
				Including	1.3	12.8	8.6	2.3	2.8	121.8	15.9	2.5	48.7

SOURCE: Meridian Mining UK S

View the original press release on ACCESS Newswire

FAQ

What are the most significant drill results from Meridian Mining's Santa Helena project?

The most significant result was from CD-701 with 25.4g/t Au and 449.0g/t Ag, representing the highest-grade bedrock gold intersection to date. Other notable results include CD-660 with 11.6m @ 5.9g/t AuEq from 42.0m and CD-700 with 17.6m @ 3.6g/t AuEq from 4.6m.

When is MRRDF planning to release the Santa Helena resource estimate?

Meridian Mining plans to release the Santa Helena resource estimate later in 2025, with resource definition ongoing through the second half of the year.

What is the significance of the Santa Fé exploration program for MRRDF?

Santa Fé, located 5km south of Santa Helena, shows expanding geochemical and IP anomalies, suggesting potential for additional mineralization. The company has mobilized a rig for shallow reconnaissance drilling in this area.

How deep is the mineralization at Santa Helena?

The mineralization at Santa Helena is relatively shallow, with significant intersections starting from as little as 4.6m below surface, making it potentially suitable for open pit mining.

What metals is Meridian Mining finding at Santa Helena?

Meridian is finding a polymetallic deposit containing gold (Au), copper (Cu), silver (Ag), and zinc (Zn) at Santa Helena.