Martello update - Completion of Initial Field Programme

13 July 2026

Richmond Hill Resources Plc

(" Richmond Hill " or the " Company ")

Martello update

Completion of Initial Field Programme

Richmond Hill Resources plc ("Richmond Hill" or the "Company") is pleased to announce the completion of its field reconnaissance and rock sampling programme across the Martello Gold Project in Ontario, Canada.

The programme was undertaken to ground-truth the priority exploration targets identified by the Company's recently completed independent 3D magnetic interpretation, while collecting geological and structural information to refine future drill targeting. Fieldwork focused on three target areas: Sakoose, Maw and Church Lake.

Highlights

• Field programme completed across three of the Company's exploration targets.
• 35 rock chip samples collected from Sakoose, Maw and Church Lake.
• Evidence identified at Sakoose that multiple quartz vein systems may be present, supporting further refinement of the Company's geological model.
• Quartz veins and veinlets mapped at each of the three target areas.
• Structural measurements collected to improve future drill targeting.
• Sulphide mineralisation observed at each target area, with hydrothermal alteration noted at Sakoose and Church Lake.
• Samples submitted for gold and multi-element analysis, with results expected during the current quarter.

At Sakoose, historical mine workings, drill pad locations and quartz vein exposures were examined. Field observations confirmed that the historically mined quartz vein locally varies from approximately 15 cm to 2 metres in thickness. Additional quartz veinlets were identified together with widespread hydrothermal alteration within both the quartz-feldspar porphyry and surrounding metabasalt. These observations provide evidence that multiple vein systems may be present and will be evaluated further following receipt of assay results.

At Maw, reconnaissance identified numerous quartz veins and veinlets hosted within gabbro and quartz-feldspar porphyry dykes. Several distinct structural orientations were recorded, indicating the presence of multiple vein sets. The field team also identified a historical excavation believed to represent the principal historical working and collected a sample from the associated stockpile. These observations will be integrated with the forthcoming assay results to prioritise future exploration.

At Church Lake, fieldwork identified additional quartz vein occurrences, historical workings and multiple structural trends. Although vegetation limited bedrock exposure in parts of the target area, several prospective zones were mapped and sampled where accessible during the programme. The work also confirmed structural orientations comparable to those recognised elsewhere across the Martello Project.

The Company believes the programme has successfully achieved its objectives of validating priority exploration targets, improving geological understanding across the Martello Project and collecting additional data to refine future exploration and drill planning.

All samples have been submitted for assay testing and the Company expects the results to be received during the current quarter (Q3 2026) and will announce the results once they have been received and interpreted.   The analytical results will be integrated with the Company's structural interpretation and recently completed independent 3D magnetic model to prioritise follow-up exploration and future drilling.

Hamish Harris, Executive Chairman, commented:

"This programme represents the first systematic field assessment of our high priority targets following the independent 3D magnetic interpretation.   The work has provided valuable new geological information from Sakoose, Maw and Church Lake and has strengthened our understanding of these priority targets.

We are particularly encouraged by the observations at Sakoose, where the field team identified evidence that multiple vein systems may be present. Together with the pending assay results, this work will help refine our geological model and support the next phase of drill targeting across the project."

This announcement contains inside information for the purposes of the UK Market Abuse Regulation and the Directors of the Company are responsible for the release of this announcement.

Richmond Hill Resources Hamish Harris	Tel: [phone]
Cairn Financial Advisers LLP (Nominated Adviser) Ludovico Lazzaretti / James Western	Tel: [phone]
Clear Capital Limited (Broker) Bob Roberts	Tel: [phone]

Further information on the Company can be found on its website at www.richmondhillresources.com

Caution regarding forward looking statements

Certain statements in this announcement, are, or may be deemed to be, forward looking statements. Forward looking statements are identified by their use of terms and phrases such as ''believe'', ''could'', "should" ''envisage'', ''estimate'', ''intend'', ''may'', ''plan'', ''potentially'', "expect", ''will'' or the negative of those, variations or comparable expressions, including references to assumptions. These forward looking statements are not based on historical facts but rather on the Directors' current expectations and assumptions regarding the Company's future growth, results of operations, performance, future capital and other expenditures (including the amount, nature and sources of funding thereof), competitive advantages, business prospects and opportunities. Such forward looking statements reflect the Directors' current beliefs and assumptions and are based on information currently available to the Directors.

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