Oriole Resources PLC 

('Oriole Resources' or 'the Company' or 'the Group')

Lithium Exploration Update, Cameroon

Oriole Resources (AIM: ORR), the AIM-quoted exploration company focussed on West Africa, provides an exploration update on the lithium potential within its 90%-owned Central Licence Package ('CLP') project in Cameroon. The district-scale CLP project comprises nine contiguous licences covering 4,091 square kilometres ('km²') of previously unexplored Paleo-Proterozoic to Pan-African age rocks that are highly prospective for a range of commodities, including orogenic-style gold mineralisation and lithium. Two of the CLP licences, Ndom and Gamboukou, are being assessed for their potential to host hard rock lithium.

Highlights

·    In November 2022, the Company reported that anomalous geochemical data from its soil sampling programmes had identified lithium-in-soil anomalism at the Ndom licence, which appeared to be associated with geological units mapped regionally as porphyritic granitoid;

·    In the same month, the Company secured the Gamboukou licence, immediately to the south of Ndom on the basis of it having similar lithium-prospective geology;  

·    Pegmatite veins within the granitoids and the older basement rocks have been confirmed within both the Ndom and Gamboukou licence areas;

·    A total of 105 rock-chip samples (including QAQC) from Ndom targeted pegmatite veins that are up to 1.5 metres ('m') wide were analysed for a multi-element suite and have returned a maximum lithium value of 39.5 parts per million ('ppm');

·    Further analysis was completed on 11 rock chip samples (including QAQC), including the 39.5 ppm sample (NDR0085), using an alternative methodology and has returned a maximum value of 35 ppm lithium, also from sample NDR0085;

·    Technical studies to assess the mineralogy of the pegmatites to help understand the mineralogy and potential lithium-bearing minerals are on-going;

·    Mapping and sampling programmes have been designed for the next field season and the Company is currently seeking an investment partner for lithium.

Oriole Resources CEO, Tim Livesey, said: "Whilst it's good to get consistent lithium results on the samples taken to date, we do need to complete further analyses and mineralogical studies to begin to understand better the initiation point for the original anomaly. 

"As we remain focused on the significant positive gold results seen to date across the five Eastern CLP licences, we will continue to run our lithium investigations in parallel and remain open to any investment interest at a project level from any lithium specialist exploration groups."

Further Details

At the CLP project (4,091km² in area), located in the centre of Cameroon, nine contiguous licences cover a land package that has significant potential for orogenic gold mineralisation and other minerals. The Company has a 90% interest in all nine licences, which it holds through local subsidiary companies.

Five of these licences, the Eastern CLP (Tenekou, Niambaram, Pokor, Ndom and Mbe), were granted in February 2021 and have been the focus of the Company's exploration to date, primarily for orogenic gold. However, a review of multi-element data from regional-scale stream and soil samples identified anomalous lithium-in-soil values (up to 84 ppm) within the east of the Ndom licence which, according to the previously established regional geology, provisionally thought to be related to pegmatites hosted within porphyritic granitoid units. Noting that comparable porphyritic granitoids underlie much of the ground to the south of Ndom, the Company applied for the Gamboukou licence, which it was able to secure in November last year (Announcement dated 29 November 2022). These comparable granitoids are present in much of the eastern and central region of the 499 km² of the Gamboukou licence.

Figure 1: Simplified summary of the prospective areas across the CLP. Lithium anomalism identified to date is located in the southeastern corner of Ndom, with the Gamboukou, and Maboum licences also having been identified as having prospective geology.

Ndom licence

The results at Ndom outlined two anomalous lithium-in-soil trends, the longest of which is 9.6km and approximately half its length overlies an east-northeast trending Pan-African age (c. 450-650 million years old) porphyritic granitoid. This area also corresponds with elevated concentrations of caesium, tin and beryllium, elements that are commonly associated with LCT pegmatites (complex pegmatites characterised by anomalous accumulations of lithium, caesium and tantalum) and/or 'fertile' or lithium enriched granites, thus strengthening the theory that the pegmatites associated with the porphyritic granitoids may have the potential to host hard rock lithium mineralisation. Assessment of the geochemical signature of soils derived from this granitoid, and smaller outcrops in the vicinity, confirms that they are predominantly highly fractioned granites, and are likely to be S-type (sediment derived) that are known globally for their association with lithium deposits. These granitoid units also extend to the southeast, within much of the Gamboukou licence area. The second lithium-in-soil linear anomaly is approximately 9.0km long, and between 2km and 4km north of, but parallel to, the east-northeast porphyritic granitoid.

Figure 2: Soil sampling results for Grid 1, covering the Ndom and Mbe licences within the Eastern CLP block, showing the elevated lithium-in-soil concentrations in eastern Ndom, overlying a mixture of migmatitic gneisses and porphyritic granitoids

In Q1-2023, the team completed detailed geological mapping, over the zone of lithium anomalism, which identified numerous pegmatite veins (ranging from centimetre scale to up to 8m wide) in the granitoid outcrops, as well as within the metamorphosed, Pan African basement rocks (greenschist to amphibolite facies, tonalite- trondhjemite-granodiorite, 'TTG'). Pegmatites were observed as individual veins, but localised areas of 'clustered' pegmatites were also observed. The abundance of mica in some specimens, and the soil geochemistry suggested that petalite and lepidolite (common lithium-bearing mica minerals) and cassiterite (a tin-bearing mineral that commonly occurs within LCT pegmatites) may be present (Announcement dated February 2023).

A total of 105 samples (including QAQC), targeting pegmatites, were analysed for a suite of 45 elements (including lithium other LCT related elements such as beryllium, caesium, rubidium and tantalum etc.) using a four-acid rock digest preparation and an ICP-MS finish. Results have returned lithium concentrations up to a maximum value of 39.5 ppm, with only nine samples returning greater than 10 ppm lithium. These results were unexpectedly lower than the lithium-in-soil data and so further assessment was merited.

According to one academic source, granitic samples with an elemental K/Br ratio of less than 150 are considered to be characteristic of pegmatite-hydrothermal evolution. Review of the multi-element data from Ndom confirmed that 20 of the 105 samples fell within this range, thus confirming the presence of pegmatite-hydrothermal influences at Ndom.

Figure 3. Discrimination plot of K/Br vs Li (ppm) for the rock chip sample analyses (both methods) at Ndom. Samples that plot below a K/Br ratio of 150 are considered to be characteristic of pegmatite-hydrothermal evolution trend.

Due to lithium-bearing minerals typically showing resistance to acid digestion, it is considered that the initial four-acid digest used in the initial sample preparation may not have been sufficient to completely dissolve the lithium. To investigate this, representative material from ten samples, were analysed (together with one QAQC sample) using a more aggressive peroxide fusion rock-digest sample preparation with an ICP-MS finish. Whilst one of the samples is a re-analysis of sample NDR0085, which returned 39.5 ppm, the remaining samples were selected on the basis of the identification (in hand specimen) of a silver-coloured mica that is tentatively considered to be lepidolite. NDR0085 returned a comparable value of 35 ppm lithium and the remaining nine samples returned values between 3 ppm and 13 ppm lithium, similar to the previous batch of rock chip samples. 

The results to date highlight the difficulties surrounding exploration for hard rock lithium. However, the elevated lithium-in-soils values still indicate a proximal source of lithium within the Ndom permit, which merits further investigation.

In addition, eight rock chip samples (three from the original batch of 105 samples and five from the new selection) were selected for X-ray Diffraction (XRD) analysis, which was completed in collaboration with University College London. This technique can be used to identify minerals according to their crystal structures. All eight samples confirmed the presence of common pegmatite minerals (quartz, feldspars, and muscovite mica) with confidence. Due to the multiphase nature of the samples, and a similar diffraction pattern of lithium bearing micas (i.e. lepidolite) to muscovite mica, the formal identification of lithium bearing micas has not been possible. However, in one sample, parts of the XRD pattern could be attributed to one of a range of micas including illite, fluorannite, trilithonite (lithium-bearing), siderophyllite, and muscovite. Furthermore, it is possible to have a range of chemistry between muscovite and lepidolite, whereby the muscovite structure can contain up to 3.3 percentage by weight ("wt%") elemental lithium (or up to 7.1 wt% lithium oxide using the conversion factor of 2.153) before altering to a lepidolite structure that would be discernible using XRD analysis. There is therefore potential for more exotic forms of mica within the samples and more investigation is required to understand the lithium potential at Ndom.

Gamboukou licence

At Gamboukou, Pan-African age porphyritic granitoid outcrops similar to those seen at Ndom have been observed along with pegmatite occurrences.

A reconnaissance visit during Q4-2022 consisted of outcrop mapping along two north-south trending lines. The eastern line was dominated by a porphyritic granitoid unit similar to the main porphyritic granitoid at Ndom, with minor influence of overlying tertiary basalts, whereas the western line was dominated by strongly sheared granodiorite overlain by a thick laterite. Pegmatites were observed along both lines, although were more prominent along the eastern line.

Continuation of mapping and sampling, along with a first-pass stream sediment sampling programme is being planned for the next field season to help with targeting. However, the Company is currently seeking a lithium-focused investment partner to help fund this work.

For further information on the CLP project, including a JORC Table 1, please see the following page of the Company's website https://orioleresources.com/projects/central-licence-package. 

Competent Persons Statement 

The information in this release that relates to Exploration Results has been compiled by Claire Bay (Executive Director, Exploration and Business Development). Claire Bay (MGeol, CGeol) is a Competent Person as defined in the JORC code and takes responsibility for the release of this information. Claire has reviewed the information in this announcement and confirms that she is not aware of any new information or data that materially affects the information reproduced here.

** ENDS **

The information contained within this announcement is deemed to constitute inside information as stipulated under the retained EU law version of the Market Abuse Regulation (EU) No. 596/2014 (the "UK MAR") which is part of UK law by virtue of the European Union (Withdrawal) Act 2018. The information is disclosed in accordance with the Company's obligations under Article 17 of the UK MAR. Upon the publication of this announcement, this inside information is now considered to be in the public domain.

For further information please visit www.orioleresources.com, @OrioleResources on Twitter, or contact:

Notes to Editors:

Oriole Resources PLC is an AIM-listed gold exploration company, operating in West Africa. It is focussed on early-stage exploration in Cameroon, where the Company has a maiden Resource of 305,000 oz Au in the JORC Inferred category at the Bibemi project and has identified multi-kilometre gold and lithium anomalism within the district-scale Central Licence Package project. At the more advanced Senala gold project in Senegal, Oriole was advised by IAMGOLD on 26 April 2023 that AGEM Senegal Exploration Suarl ('AGEM') was now a wholly-owned subsidiary of Managem Group. As previously announced, AGEM has earned an initial 51% beneficial interest by spending US$4 million and has the option to spend up to a further US$4 million by 28 February 2024 to earn a further 19% interest. Reverse Circulation drilling is planned as part of AGEM's Year 6 programme at Senala. The Company also has several interests and royalties in companies operating in East Africa and Turkey that could deliver future cash flow.