High Grade Potential At Ampasindava

31 March 2025

Citius Resources Plc (to be re-named Harena Resources Plc)

("Harena" or the "Company")

Historical Exploration Data Review Highlights High Grade Potential At Ampasindava

Highlights:

·    Extensive trench and pit sampling confirm high integrity and elevated TREO grades

·    30,059 samples from 4,474 vertical pits with some max grades up to 14,995 ppm TREO and 39,098 ppm TREO

·    242 samples across five trenches returned max grade up to 3,663 ppm TREO and 4,589 ppm TREO

·    Vertical pits (1m by 1m up to 10m deep) provided extensive channel sampling coverage

Harena (LSE:HREE) is pleased to provide an update on the Ampasindava Rare Earths Project ("Project") in north-eastern Madagascar.

Following a detailed review of historic exploration data that formed the basis for the current Mineral Resources Estimate ("MRE") of 698.5 million tonnes measured, indicated and inferred JORC 2012 compliant Resource reported on 1 November 2023 by SGS (and incorporated in the Company's prospectus dated 26 February 2025), the Company has identified significant high-grade rare earth zones.

The MRE supports a potential mine-life of over one hundred years. This potential longevity creates flexibility in mine planning and the opportunity to target high grade zones during critical start up years. This forms part of the Company's strategy to enhance near-term project economics and cash flow generation.

Early High-Grade Potential Confirmed

The Company's technical team has review all available historic exploration data from trenching, sinking vertical pits, and 277 diamond drill holes. This work confirms the potential for early stage high-grade mining operations and mine plan optimisation.

Additionally, the advanced level of exploration and feasibility work already completed on the Project, presents further opportunities for to optimise mine planning optimisation across the ionic clay rare earth element ("REE") deposit.

Joe Belladonna, Managing Director, commented:

"This review highlights the value of acquiring a mature project with substantial historic exploration and development spend. I am particularly pleased that the team is identifying project optimization potential from day one - particularly through high-grade zones. The impact of high grading in the early years is forecast to drive robust economics especially in the early years of production."

Summary of Key Technical Information

An assessment of the sampling and analysis collected as part of the MRE highlighted the presence of several high grade zones hosting Total Rare Earth Oxides ("TREO") grades substantially higher than the mineral Resource average calculated grade. As we undertake mining planning, this allows mine planners to target these high-grade zones in preference.

1.         Pitting

A total of 4,474 pits were manually excavated for the purposes of assessing regolith hosted REE mineralisation. They are vertical pits typically 1m x 1m with a depth of up to 10m, with an average depth across the orebody of 5.68m. These have now been excavated over six prospect areas with pit spacing ranging from 50m to 250m.

Ideally the pits were excavated to bedrock. However, for safety reasons the pits were not excavated deeper than 10m. Once a pit was excavated, the sampling methodology involved marking out the samples on the same wall of each pit at 0.5m or/and 1.0 m intervals. Samples were collected from the lowermost interval first to minimise contamination.

All of the pits were back-filled as soon as geological observations, density measurements, moisture readings and sampling were completed.

The lithology identified within the Ionic Clay regolith zone are an upper zone of pedolith overlying a saprolith hosting saprolite and the transition to saprock. Table 1. below lists the analyses from the pitting campaigns, making up the largest portion of the assay database.

Notable amongst these results are the Max results for the Pedolith of 14,999 ppm TREO and for the Saprolith of 39,098 ppm TREO indicating that the mineralisation is skewed towards the saprolite layer, closer to the underlying volcanic breccia.

The very low minimums found in some pits indicates that some were excavated in clays which sit outside the volcanic breccia providing the REE feedstock. This diverse range of minimums and highs is not present in the trenching results.

These results, while still to be tested, provide flexibility in mining and targeting higher grade material for the planned initial heap leach production.

 Table 1. Summary of Analyses from Ampasindava Pitting Campaigns

2.         Trenching

A brief assessment of the trenching exercise conducted at Ampasindava revealed that areas underlain by volcanic breccia appear to have elevated TREO, Niobium (Nb) and Tantalum (Ta) grades. The trenches were about 3m deep, up to 100m long and most did not reach bedrock.

The summary trench sample results show an interesting trend. Whilst the average TREO (ppm) results for the west (Befitina and Caldera) are similar, those for the other rare metals are evidently dissimilar. This is an interesting trend that can be explained by the differences in lithological setting, with the west prospect comprising sedimentary rocks that contain mineralised intrusives that host certain rare metals and the east prospect that is predominantly volcanic breccia. From an economic perspective, it suggests that the regolith material is similarly enriched in REEs.

This is significant as it also substantiates the prospectivity of areas underlain by volcanic breccia in line with those underlain by mineralised intrusive rocks. However, it should be noted that this is too small a dataset on which to make definitive conclusions and warrants further follow up work.

Table 2. Summary of the Trench Sample Results (Gilbertson 2013)

Block Model TREO values

In developing a 3D Block Model for the Resource, the modeller determined the area of the Resource that hosted grades of between 1,000 ppm TREO and 2,000 ppm TREO. As can be observed in the image below, these extensive areas are contiguous to the east of the resource and whilst a mining reserve has not yet been determined, it is clear that an initial focus on the red areas, if possible, will provide a mining grade higher than the published resource grade.

Image 1. Oblique Section Showing Block Model TREO Values and Deposit Contours.

References:

1.   Independent Specialist Report by SGS - Ampasindava Rare Earths Project - August 20 2024

2.   Mineral Resource Report by SGS - Ampasindava Rare Earths Project - November 2023

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Notes to Editors

Harena Resources is a rare earths exploration and development company that holds a 75% interest in the on the Ampasindava Ionic Clay Rare Earth Project in Madagascar. The project hosts one of the largest ionic clay rare earth deposits outside of China, with significant concentrations of high-value magnet metals. Harena is committed to low-impact, high-recovery mining, providing a sustainable supply of critical minerals for the global energy transition and military defence industries.

Forward-Looking Statements This announcement contains forward-looking statements that involve risks and uncertainties. Actual results may differ materially from those expressed or implied in such statements.