Zinnwald Lithium plc / EPIC: ZNWD.L / Market: AIM / Sector: Mining

21 February 2024 

Zinnwald Lithium plc ("Zinnwald Lithium" or the "Company")

445% Increase in Mineral Resource Estimate

Zinnwald Lithium Project established as the second largest hard rock lithium project in the EU

Zinnwald Lithium plc, the European focused lithium company, is pleased to announce the publication of an updated independent Mineral Resource Estimate ("MRE") for its 100% owned Zinnwald lithium project ("Zinnwald" or the "Project") located in Saxony, eastern Germany.

The 2024 MRE update incorporates 26,911 metres of new diamond core drilling across 84 drill holes and a reinterpreted and updated geological model since the previous MRE which was released in September 2018.

In addition to the high-grade greisen mineralisation, focus of the recent 2022/2023 drilling was the lithium mineralisation hosted by the broader zone of altered albite granite, which includes internal lenses of higher-grade greisen. The inclusion of this mineralised zone allows for a higher production rate and a potential optimisation of overall project economics. 

2024 Resource Highlights:

·    A 445 % increase in tonnes and a 243% increase in contained lithium ("Li") in the Measured and Indicated category versus the previous 2018 MRE.

·    Total contained Li of 429kt compared with the 2018 MRE of 125kt in the Measured and Indicated category.

·    11.3 Mt grading 3,420ppm Li (0.736% Li₂O) in the Measured category.

·    193.5 Mt grading 2,220ppm Li (0.478% Li₂O) in the Measured and Indicated category.

·    33.3 Mt grading 2,140 ppm Li (0.461% Li₂O) in the Inferred category.

·    Increase in overall tonnage predominantly due to the incorporation of a broad zone of mineralised granite, as well as contribution of an extra 26,911 metres of new drilling over 84 holes.

·    Measured classification only applied to the external greisen domains due to a higher metallurgical confidence; Snowden Optiro recommends further metallurgical variability testwork in the broad mineralisation zone domain to further increase confidence.

·    Demonstrated dimensions of the mineralised zone (true thickness c. 80 metres) and continuity of ore supports highly efficient mining methods with minimal waste rock production.

·    Mineral Resources reported using a 1,100ppm Li cutoff grade and a stope optimisation to constrain an RPEEE Resource.

Zinnwald Lithium CEO, Anton du Plessis, commented: "We are delighted to be able to announce a substantial increase of our Mineral Resource at the Zinnwald Project with a 3.4x increase in contained lithium in the Measured and Indicated categories. This establishes the Project as the second largest hard rock lithium project by both resource size and contained lithium in the EU and clearly highlights its scale and strategic importance. 

"The inclusion of the mineralised granite in the resource and ultimately the mine plan will allow more efficient bulk underground mining techniques with the potential to meaningfully increase the lithium production from what was contemplated in the PEA published in 2022."

Detailed Information

The following statement of Mineral Resources has been prepared in accordance with National Instrument 43-101 Standards of Disclosure for Mineral Projects of the Canadian Securities Administrators ("NI 43-101") by independent consulting firm Snowden Optiro Ltd ("Datamine International") of Bristol, United Kingdom. 

Table 1.1               Mineral Resource Statement for Zinnwald Lithium Project, effective 20^th February 2024.

Notes

§  Mineral Resource statement has an effective date of 20^th February 2024.

§  A Mineral Resource is reported using a cut-off grade of 1,100 ppm Li, which was calculated using the following assumptions: lithium hydroxide monohydrate price USD 23,800 /t, operating costs of USD $ 121.5/ t ROM; Li recovery of 69%; mining dilution and recovery of 10%.

§  The requirement of a reasonable prospect of eventual economic extraction is met by having a minimum modelling width for mineralized zones, a cut-off grade based on reasonable inputs and an economic binding volume that lends itself to a potential scenario of underground extraction for undiluted in-situ resources.

§  The Mineral Resource is reported at a minimum of 20m below historical underground mine workings (to avoid historic underground workings), and within Germany only.

§  All tonnages reported are dry metric tonnes.

§  Minor discrepancies may occur due to rounding and use of appropriate significant figures.

§  LCE (lithium carbonate equivalent) calculation used - 5.323 x Li metal. LiOH*H2O (lithium hydroxide monohydrate) calculation used - 6.045 x Li Metal.

§  Mineral resources which are not mineral reserves do not have demonstrated economic viability. An Inferred Mineral Resource has a lower level of confidence than that applying to an Indicated Mineral Resource and must not be converted to a Mineral Reserve. It is reasonably expected that the majority of Inferred Mineral Resources could be upgraded to Indicated Mineral Resources with continued exploration.

§  The results from the stope optimization are used solely for the purpose of testing the "reasonable prospects for economic extraction" by underground methods and do not represent an attempt to estimate mineral reserves. There are no mineral reserves reported in this NI 43-101 resource update. The results are used as a guide to assist in the preparation of a Mineral Resource statement and to select an appropriate resource reporting cut-off grade. Stope optimisation does not represent an economic study.

§  The estimate of Mineral Resources may be materially affected by environmental, permitting, legal, title, taxation, socio-political, marketing, or other relevant issues.

§  The Author is not aware of any known mining, processing, metallurgical, environmental, infrastructure, economic, permitting, legal, title, taxation, socio-political, or marketing issues, or any other relevant factors, that could materially affect the current Mineral Resource Estimate.

Mineral Resource Estimate

Zinnwald Lithium has recently completed an infill drilling campaign in order to increase confidence in the geological block model and to produce an updated MRE. This update to the MRE has been completed in conjunction with other technical work contributing to an updated feasibility study.

This MRE required a reinterpretation and an updated geological model in order to represent the geological and mineralogical domains that have been defined by the most recent drilling campaign undertaken by the Company during 2022 and 2023. The geological model includes mineralisation domains that are represented by the higher grade greisens "external", as well as a broader zone of lithium mineralisation contained within a mineralised albite lithium mica granite and "internal" higher grade greisens. The higher-grade external greisens are narrow in places but can reach up to 40 metres in true thickness, they outcrop above the mineralised zone of granite and internal greisens, with a typical separation but variable distance of approximately 10 metres. The broader mineralised zone has an average true thickness of approximately 80 metres and contains lenses of greisen that locally exhibit higher grades of lithium mineralisation. Both the mineralisation zone and the greisens mirror the strike and dip of the host rock intrusion- the albite granite, as is typical of many greisen related roof zone deposits.

Lithium mineralisation within all geological domains is hosted exclusively by polylithionite micas, or better known as "zinnwaldite" type micas.

Lithium has been estimated using ordinary kriging methods and density using simple kriging methods. Estimation has honoured the hard boundaries of the external greisens, internal greisens and mineralised granite domains, as well as using a dynamic anisotropic search method to honour the varying dip and dip directions of all estimation domains (Figure 1.2, Figure 1.3 and Figure 1.4).

This updated MRE differs from the previous MRE, completed in 2018, by incorporating the broader mineralised zone. The incorporation of the mineralised zone has allowed for a higher production rate and a reduction in unit processing costs.

Figure 1.2 - 3D view looking north west. Updated resource block model showing distribution of lithium metal (Li_ppm) grades

Block model showing lithium (Li_ppm) grade distribution.

Figure 1.3 - North-South long section through the resource block model.

Block model showing lithium (Li_ppm) grade distribution, red line denotes reportable limit as defined by a 20-metre safety pillar below historical mine workings, black line denotes topography.

Figure 1.4 - West-East cross section through the resource block model.

Block model showing lithium (Li_ppm) grade distribution, red line denotes reportable limit as defined by a 20-metre safety pillar below historical mine workings, black line denotes topography.

Classification

Snowden Optiro has taken multiple factors into account when considering classification:

·    Drillhole spacing

·    Geological model confidence

·    Mineralisation continuity

·    Metallurgical confidence

·    Estimation pass

·    Mineralisation thickness

The classification criteria for the resource are as follows:

·    Measured: External greisen units, below the 20 metre safety buffer, showing consistently mineralised zones supported by several drilling intersections at a spacing of approximately 80 metres.  This corresponds to parts of the model where the geo-metallurgical behaviour is well understood, and the mineralisation shows suitable continuity.  The classification does not include any extrapolated material beyond appropriately spaced drillholes and must be estimated in the first search pass.

·    Indicated: External greisen units and the mineralisation zone, below the 20 metre safety buffer, supported by drilling intersections on a spacing of 80-120 metres.  The classification does not include any extrapolated material beyond appropriately spaced drillholes and must be estimated in the first search pass.

·    Inferred: External greisen units and the mineralisation zone, below the 20 metre safety buffer, supported by wider-spaced drilling.  This corresponds to less certainty in geological / mineralisation continuity and consists of material estimated in the first and second pass and extrapolated beyond drillholes at the periphery of the model up to half drillhole spacing.

It is the opinion of Snowden Optiro that given the metallurgical understanding of the mineralisation zone of the albite granite, it would not be appropriate to apply a classification of higher confidence than Indicated to the broad mineralisation zone. Snowden Optiro considers that due to lower mineralogical variability within the high grade greisens, and greater metallurgical test work coverage, portions of the high-grade greisen can be classified as Measured.  Snowden Optiro has recommended to Zinnwald Lithium that a geo-metallurgical testwork program be undertaken to provide a higher level of confidence in the Mineral Resource within the broader mineralisation zone. Snowden Optiro has provided Zinnwald Lithium guidance in sample selection and the metallurgical testwork programme.

Reasonable Prospects for Eventual Economic Extraction

NI 43-101 defines a mineral resource as that portion of the mineral inventory that has reasonable prospects for economic extraction ("RPEEE").  CIM Best Practice Guidelines for estimating mineral resources require the factors significant to project economics be current, reasonably developed and based on generally accepted industry practice and experience. In establishing the cut-off grade, it must realistically reflect the location, deposit scale, continuity, assumed mining method, metallurgical processes, costs and reasonable long-term metal prices appropriate for the deposit.

Key assumptions have been provided to Snowden Optiro by Zinnwald Lithium for this MRE; these have been adjusted in accordance with the Company's understanding of costs associated with a higher production rate expected when mining a greater volume of material at a lower grade.  This includes metallurgical recoveries and mineral processing costs based on the results of ongoing metallurgical testwork.

The grade-tonnage curve in Figure 1.5 demonstrate the robustness of the estimation to changes in cut-off grade around the 1,100 ppm Li grade.

Figure 1.5 - Grade-tonnage curve for the Zinnwald Lithium deposit, Measured and Indicated only.

Comparison with Previous Estimates

The most recent MRE for the deposit was completed on 30 September 2018 by G.E.O.S. Ingenieurgesellschaft GmbH and was prepared using the terminology and definitions given in the Canadian securities National Instrument 43-101 Standards of Disclosure for Mineral Projects ("NI 43-101"). The previous MRE focussed only on the greisens and not on the mineralised granite. The Snowden Optiro updated MRE has included the mineralised granite and incorporated internal greisens within a mineralised zone. A direct comparison is provided in Table 1.3, noting that the mineralised zone contains greisens as defined as type 1 in the 2018 MRE.

Table 1.3 - Comparison of the GEOS 2018 MRE with the updated Snowden Optiro 2024 MRE

Cut-off grade used for the GEOS 2018 MRE was 2,500ppm (due to lower expected processing throughputs) and 1,100ppm for the Snowden Optiro 2024 MRE.

The 2024 MRE shows a 445 % increase in tonnage in the Measured and Indicated category over the 2018 MRE. This is predominantly due to the incorporation of the broad mineralised zone, as well as the significant increase in drilling meters (27,000m) and sampling intervals contributed by the 2022-2023 campaign. A slight drop in the Measured category is in part due to the incorporation of internal greisens within the mineralised zone, and a more appropriate classification of higher confidence parts of the resource, taking into account, drillhole spacing, geological model confidence, mineralogical & metallurgical confidence and estimation quality. Snowden Optiro has recommended to Zinnwald Lithium that further metallurgical testing of the mineralisation zone be undertaken in order to convert parts of the mineralised zone currently defined as Indicated.

Qualified Persons

Laurie Hassall, Senior Consultant, MSci FIMMM '689775' FGS '1044219', of Snowden Optiro is the main author of the 2024 MRE and is responsible for the technical information in this announcement.  Mr Hassall is a Qualified Person under the terms of NI 43-101 and is independent of the Company.

In accordance with the AIM Rules - Note for Mining and Oil & Gas Companies, the information in this announcement has been reviewed and approved by Qualified Person EurGeol (#641) Christian Masurenko of Zinnwald Lithium, Dipl. Geo., Member EFG, Fellow SEG

*ENDS*

 For further information visit www.zinnwaldlithium.com or contact:

Notes

AIM quoted Zinnwald Lithium plc (EPIC: ZNWD.L) is focused on becoming an important supplier of lithium hydroxide to Europe's fast-growing battery sector. The Company owns 100% of the Zinnwald Lithium Project in Germany, which has an approved mining licence, is located in the heart of Europe's chemical and automotive industries and has the potential to be one of Europe's more advanced battery grade lithium projects.

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