Castle Minerals Limited - Additional Graphite Targets at Kambale

Castle Minerals Limited (ASX: CDT) ('Castle' or the 'Company') advises that a 275-line km ground electromagnetic geophysical survey at its flagship Kambale Graphite Project, Ghana ('Project') has identified 13 priority-one targets to be evaluated for possible additional graphitic schist occurrences. (Fig 1).

The survey used state-of-the-art, low-impact Loupe EM technology to evaluate the broader 149km2 Kambale licence for mineralisation additional and distal to the maiden JORC Code (2012) Mineral Resource Estimate ('MRE') of 15.6Mt at 9.0% TGC containing 1.41Mt of graphite that was delineated earlier in 2023 (ASX release 12 April 2023). Data processing also highlighted 33 priority-two anomalies and provided very useful high-resolution information on local structural fabric and mineralisation controls. The east-west EM survey lines extended between 200m and 3,950m and were spaced variably between 50m, 100m and 200m. Where there was overlap, the Loupe EM survey data compared well with data from a more focused HLEM survey undertaken in early-2022 (ASX release 31 March 2022). Processing of the HLEM data highlighted a series of modelled conductor plates that proved, in a majority of cases when drill tested, to be associated with graphitic mineralisation. The results of a recently completed infill 43-hole, 5,355m RC drilling programme, also guided largely by the HLEM, will be available later in August along with an update to the current MRE. This is expected to deliver a material increase in the MRE for the deposit (ASX release 16 May 2023). EM is clearly a very useful tool in identifying graphitic schists at Kambale. With still only half of the available prospective area covered by EM surveys, there remains considerable scope for more anomalies to be identified. A concurrent metallurgical test work programme is evaluating the Kambale graphitic material to produce a fine flake graphite bulk concentrate of commercially acceptable specifications. This is forecast to be completed mid-August and results reported in the weeks following. Castle has a well-defined strategy to fast-track the Project to coincide with the widely forecast looming supply deficit for fine flake concentrate which is a major input in the manufacture of electric vehicle batteries and stationary power storage units. Graphite is designated a Critical Mineral by the USA, the EU, Japan and Australia

Castle Managing Director, Stephen Stone, commented....'Knowing that a previous EM survey was successful in identifying additional graphitic schists at Kambale, we are naturally very keen to test this latest series of 13 priority-one targets identified by the recent Loupe EM survey. Kambale already hosts a sizable 15.6Mt Mineral Resource grading 9.0% TGC containing 1.41Mt of graphite and we are hopeful of materially increasing this when we process the results of the just completed 43-hole, 5,335m infill RC drilling programme.

Any additional material located on the broader licence area using the Loupe EM data will improve options for optimising a mining and on-site processing operation. Plus, we have still only surveyed 50% of the available prospective area.

We will be kicking-off a Scoping Study later in the year to begin evaluating the merits of establishing a mining and processing operation at Kambale. This will incorporate results from metallurgical test work aiming to produce a fine flake graphite bulk concentrate of commercial specifications. This is due to be completed mid-August and reported in the weeks following. Castle continues to fast-track the Kambale Graphite Project to coincide with a widely forecast looming supply deficit for fine flake concentrate which is a major input in the manufacture of electric vehicle batteries and stationary power storage units. Graphite is designated a Critical Mineral by the USA, the EU, Japan and Australia.'

KAMBALE PROJECT BACKGROUND

Geology The Kambale graphite deposit was identified in the 1960s by Russian geologists prospecting for manganese. They undertook a limited programme of trenching and shallow drilling. The genesis of the flake graphite in Kambale is believed to be the result of high-grade metamorphism (amphibolite-granulite facies) which has converted trapped amorphous carbon into characteristic fine crystalline layers

2012 drilling

Encouraged by firm graphite prices in 2012, Castle undertook three consecutive phases of drilling comprising RAB (251 holes, 5,621m), aircore (89 holes, 2,808m) and reverse circulation (3 holes, 303m). This work confirmed several zones of moderately to steeply dipping, north-east trending graphitic schists hoisted mainly in granodiorites. A JORC Code 2006 MRE was also undertaken. A review of a wide-spaced, regional-scale electromagnetic survey dataset inherited by Castle from previous licence holder, Newmont Limited, outlined a roughly elongate, north-south orientated, 10kmlong region that could be considered prospective for graphitic schist horizons. Castle also undertook a very limited programme of bench-scale test work on RC chips. Thereafter, little work was undertaken until the more recent improvement in graphite prices prompted a re-evaluation of the Project in early-2021.

Graphite market

The graphite market is diverse across industrial, metallurgical, chemical and specialised areas with each sector requiring reliable long term supplies of graphite concentrates with very specific qualities. Deposit type, size and geometry, flake size, flake shape, grade, impurities, capital and operating costs, ability to be refined, proximity to specific markets, supply logistics, jurisdiction, fiscal regime and many other factors all combine to determine the commercial viability of a particular deposit. The current medium to long term outlook for the broader graphite concentrates market is one of escalating demand and a looming supply deficit driven in particular by its use in the fast-growing EV battery and stationary power storage sectors. At present, there is no viable high-volume substitute for graphite whether that be natural flake or its synthetically manufactured form which involves a considerably higher CO2 generating process. Given the wide variety of uses and required specifications and volumes, the market and pricing for graphite is very opaque. The reader is directed to numerous recent publications, conference proceedings, market research papers and corporate websites of companies engaged in graphite exploration, project development or production for informed commentary and analysis of the graphite market

Authorised for release to ASX by the Board of Castle Minerals Limited: Stephen Stone Managing Director [e-mail] [phone]

About Castle Minerals Limited

Castle Minerals Limited is an Australian Securities Exchange (ASX: CDT) listed and Perth, Western Australia headquartered company with interests in several projects in Western Australia and Ghana that are prospective for Battery Metals (lithium and graphite), base metals (zinc, lead and copper) and gold. The Earaheedy Basin project comprises the Withnell and Terra Rossa sub-projects with the Withnell licence strategically located adjacent to the evolving World-Class Chinook-Magazine zinc-lead project of Rumble Resources Ltd (ASX: RTR) and north of the Strickland Metals Limited (ASX: STK) Iroquois prospect. The Terra Rossa licences have additional prospectivity for copper. The Beasley Creek project is prospective for gold and lithium and lies on the northern flanks of the Rocklea Dome in the southern Pilbara. The Success Dome project lies in the Ashburton structural corridor midway between the Paulsen's and Ashburton gold deposits and is prospective for gold and base metals. The Polelle project, 7km southeast of the operating Bluebird gold mine near Meekatharra, hosts a mainly obscured and minimally explored greenstone belt prospective for gold and possibly base metals whilst the Wanganui project is prospective for down-plunge high-grade gold shoots. The Wilgee Springs project, along strike from and within the same metamorphic belt as the world-class Greenbushes lithium mine 25km to the south, is prospective for spodumene bearing pegmatites as is the Woodcutters project, 25km south east of the Bald Hill lithium mine and 25km north west of the Buldania lithium deposit. The Woomba Well project will also be evaluated for lithium bearing pegmatites. The Great Southern Graphite project comprises granted licences encompassing the historical Kendenup graphite workings and the adjacent Martagallup graphite occurrences and one application covering a graphite occurrence at Mt. Barrow. In Ghana, West Africa, Castle's substantial and contiguous tenure position in the country's Upper West region encompasses large tracts of highly prospective Birimian geological terrane, the host to many of West Africa's and Ghana's multi-million-ounce gold mines. The emerging flagship Kambale Graphite Project lies within the Ghana tenure. Castle retains a 4% net smelter precious metal royalty over the Julie West licence, a key component of Azumah Resources Limited's Wa Gold Project, Upper West region, Ghana.

Cautionary Statement

All of Castle's projects are considered to be of grass roots or of relatively early-stage exploration status. Other than for the Ghana projects, there has been insufficient exploration to define a Mineral Resource.

No Competent Person has done sufficient work in accordance with JORC Code 2012 to conclusively determine or to estimate in what quantities gold or other minerals are present. It is possible that following further evaluation and/or exploration work that the confidence in the information used to identify areas of interest may be reduced when reported under JORC Code (2012).

Forward Looking Statement

Statements regarding Castle's plans, forecasts and projections with respect to its mineral properties and programmes are forward-looking statements. There can be no assurance that Castle's plans for development of its mineral properties will proceed. There can be no assurance that Castle will be able to confirm the presence of Mineral Resources or Ore Reserves, that any mineralisation will prove to be economic or that a mine will be successfully developed on any of Castle's mineral properties. The performance of Castle may be influenced by a number of factors which are outside the control of the Company, its Directors, staff or contractors.

Competent Persons Statements

The scientific and technical information in this Report that relates to the geology of the deposits and exploration results is based on information compiled by Mr Stephen Stone, who is Managing Director of Castle Minerals Limited. Mr Stone is a Member of the Australian Institute of Mining and Metallurgy and 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 and Ore Reserves'. Mr Stone is the Qualified Person overseeing Castle's exploration projects and has reviewed and approved the disclosure of all scientific or technical information contained in this announcement that relates to the geology of the deposits and exploration.

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