New Mineral Resource Statement Zulu
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Premier African Minerals Limited ("Premier" or the "Company"), is pleased to report a new SAMREC compliant Mineral Resource Estimate ("MRE" or "Mineral Resource Estimate") on its wholly owned Zulu Lithium and Tantalum Project ("Zulu"). The previous Mineral Resource Estimate issued on 6 June 2017 is simultaneously withdrawn.
Highlights
| Ø | This MRE is concerned with those areas of the Zulu tenements that are expected to be mined and processed through the present plant only and excludes the greater EPO area. |
| Ø | This MRE estimates Li 2 O that is contained in spodumene, specifically Li 2 O that is attributable to spodumene at 107,366 tonnes and the direct conversion of the contained Li 2 O to spodumene concentrate 6 (SC6) is 1,789,433 tonnes. |
| Ø | This MRE estimates that the ore body contains 1,045,908 kg of Ta 2 O 5 . |
| Ø | On-going Mineral Resource development drilling, with the aim of identifying extensions to the current MRE and thereto having the potential to add additional Mineral Resources, is ongoing. |
George Roach, CEO commented: "This MRE supports the development of the Zulu mine on an expedited basis. It underlines our confidence in the medium and long-term future of this mine and further supports our view that Zulu has the stand-alone potential to develop a Lithium Sulphate plant. Work continues in the greater EPO area, and we have now identified areas of future potential mineralisation and secured those areas in the longer term under new mineral claims.
It is worth noting that this MRE is based on an assumed 80% of the total Li2O grade of the ore body being attributable to the SQI dominant style of mineralisation, which is conservative in our opinion and ongoing analysis of the mineral assemblage may support an increase in this percentage with potential increases in the contained spodumene. We have previously set out our expectation that Zulu is likely to produce spodumene concentrates with low iron and higher spodumene concentrate grades.
Accordingly, we expect to receive a premium for spodumene concentrates produced at Zulu and this further supports our determination to bring this plant into production now. Whilst we do not have the ability to recover tantalite at present, relatively minor plant additions that are under consideration are expected to see production of Ta2O5 concentrate in the future.
At the same time, I am pleased to note the arrival at site of all plant components and in particular the arrival and installation of the new ball mill. Assembly is expected to complete within the next weeks. Optimisation of the sorters is ongoing, and we expect the overall plant to be back in production during February 2024."
Mineral Resource Estimate:
The MRE is based on assay results from 163 drill holes totalling 33,258 metres (m) drilled between September 2016 and the end of August 2023. This MRE was carried out by an independent qualified person, Mr Charles Muller of Shango Solutions (Shango). All available data was verified prior to the development of the 3-dimensional geological model which was completed utilising Datamine Studio RM.
The geological model has been developed from extensive drilling, which was undertaken on a nominal 50 m x 50 m drill spacing, as well similarly spaced surface trenches. Variography indicates that 50 m spacing of the borehole pierce points is sufficient for an Indicated Mineral Resource classification.
The MRE set out in Table 1 is prepared in accordance with SAMREC and in compliance with Appendix 3 of the AIM Note for Mining and Oil & Gas Companies. In this regard, specific attention is drawn to the fact that Zulu is expected to produce spodumene concentrate and certain by products. Not all Li2O identified in assay results is contained in spodumene, with ongoing test work indicating that spodumene accounts for more than 80% of the Li2O grade. Accordingly, the overall tonnage of the Mineral Resource is reduced to reflect only the contained Li2O that is associated with spodumene. Premier is the Operator and 100% owner of Zulu such that the gross and net attributable MRE attributable to Premier is the same.
Table 1: Mineral Resource Statement for Zulu Project - 31st January 2024
| Tonnage | Grade | Metal | |||
| Category | Mt | Li 2 O | Ta 2 O 5 | Li 2 O | Ta 2 O 5 |
| % | g/t | t | kg | ||
| Indicated | |||||
| 14.78 | 0.45 | 43.83 | 66,498 | 647,687 | |
| Inferred | |||||
| 9.97 | 0.41 | 39.95 | 40,869 | 398,222 | |
| Indicated and Inferred | |||||
| 24.75 | 0.43 | 42.20 | 107,366 | 1,045,908 | |
| Notes | |||||
| i. | Losses: delineated pegmatites contain 80% spodumene - tonnage is reduced by 20% to reflect the mineral assemblage. In addition, geological losses of 5% for Indicated Mineral Resources and 10% for Inferred Mineral Resources have been applied. | ||||
| ii. | The MRE is prepared at a 0 % cut-off grade as all the spodumene is expected to be recovered. | ||||
| iii. | A density of 2.78 g/cm3 has been utilised. | ||||
| iv. | A depth cut-off of 300 m below surface has been considered based on cost parameters, although the majority of the pegmatites have only been modelled to a depth to 200 m. | ||||
| v. | The effective date of the MRE is 31 January 2024 | ||||
| vi. | The MRE is based on information compiled by the Company and reviewed by Shango and prepared in accordance with SAMREC. Mineral Resources are not Mineral Reserves and have not demonstrated economic viability. | ||||
| vii. | The contained Li2O and Ta205 metal values are rounded, actual grades and contained metal are accurately stated and any differences in the totals are due to rounding. | ||||
About Zulu:
Zulu comprises 14 mineral claims covering a surface area of 3.5 km² that are contained within a larger Exclusive Prospecting Order (EPO), and which are prospective for tantalum and lithium mineralisation. The project is located 80 km as east of Bulawayo. Fort Rixon is some 15 km further to the west of the project; the nearest village is Pioneer Village n°2, approximately 1 km to the south of the main deposits.
Geological Setting:
The area of interest is located within the Fort Rixon Greenstone Belt where the schist belt is north-south trending and tear drop shaped, measuring 30 km long in and 19 km wide near the broad section near the northern end of the belt.
The central area of the claims are underlain by Archaean-age schists of the Bulawayan Supergroup, with serpentinites and banded iron formations at the base of the Upper Bulawayan Group in the east, and metamorphosed mafic volcanics (amphibolites) and sediments of the Lower Bulawayan Group to the west. The principal pegmatites at Zulu (the Main and South pegmatites) are developed along the contact of the Upper and Lower Bulawayan groups. Additional pegmatites are developed in the footwall sediments. The metamorphic grade is retrograde Greenschist facies. In the east of the claims blocks, epidosites, calc-silicate rocks and gneissic granites prevail. The northern most part of the EPO is underlain by a post-Bulawayan Supergroup aged massive granite.
The Zulu pegmatites are typical Lithium-Caesium-Tantalum (LCT) pegmatites. Outcrop widths for the exposed pegmatites can vary between 1 m to 50 m.
The strikes of the individual pegmatites may varies widely but the South, Main and NE pegmatites and their subsidiary footwall pegmatites trend approximately NNE. The short strike length petalite-rich River Pegmatites trend in an approximate SW-NE direction, while the SE Pegmatites strike in a NW-SE direction. Although dips can vary locally with each pegmatite, the dip of the South and Main pegmatites is generally subvertical towards the west, while the River Pegmatites are dipping subvertical to the NW and the SE Pegmatites subvertical to the SW.
The South and Main pegmatites have exploited the serpentinite-amphibolites contact with the subsidiary footwall pegmatites mainly hosted in the amphibolite sediments. In the east the pegmatites are hosted in granites.
The drilled widths of individual pegmatites can vary from less than a metre to greater than 20 m in thickness down hole. Occasionally along the contacts between the pegmatites and the host amphibolites, the individual pegmatites have undergone intense sodium metasomatism resulting in the formation of a lithium bearing amphibole called holmquistite.
Lithium Mineralisation at Zulu:
To date, three principal lithium bearing minerals, spodumene, petalite and lepidolite have been identified in the Zulu pegmatites. Locally the host rocks of the pegmatites contain noteworthy amounts of holmquistite, a lithium bearing amphibole.
Tantalum Mineralisation at Zulu:
Many of the lithium bearing pegmatites at Zulu are weakly mineralised with tantalum with the best mineralised pegmatite being the South Pegmatite (South Pit) having an overall Indicated Mineral Resource grade of 86 ppm Ta2O5. The only tantalum bearing mineral observed to date is tantalite. The highest tantalum grade to date is 3,203 ppm Ta2O5 from a surface trench.
Exploration History:
The pegmatite was first pegged in 1955 by J.S. Willemse. Subsequently the Rhodesian Selection Trust Co. Ltd. ("RST") took an option on the claims and carried out an extensive drilling and excavation programme. Although much development work was carried out, the RST declined to exercise their option on the claims. In 1961 and 1962 a small quantity of petalite was mined by W. Burchett in partnership with J.S. Willemse.
In 2010, after decades of no activity, consulting geologist Richard B. Dollar registered the claims in his name and subsequently carried out diamond drilling and trenching programmes which were financed by Premier. In 2013 the Company exercised an option to acquire the claims.
Drilling Techniques and Hole Spacing:
All the boreholes available for the Mineral Resource estimation were diamond drill boreholes. The drilling and trenching statistics for each exploration phase are detailed in Table 2.
Table 2: Zulu Drilling Statistics
| PROGRAMME | Drill Holes | Surface Trenches | ||
|---|---|---|---|---|
| No. | Metres | No. | Metres | |
| RST (1958) | 7 | 903.9 | ||
| ZULU - 2011 Exploration | 6 | 2,312.9 | ||
| ZULU - 2016-2017 | 43 | 5,809.1 | ||
| ZULU - MRE (2021-2023) | 143 | 34,100.2 | 33 | 2,534.8 |
| TOTAL | 199 | 43,126.1 | 33 | 2,534.8 |
In 2011, six diamond drill holes totalling 2,312 m were drilled by Ox Drilling from Zambia. Core diameters ranged from PQ (85 mm) PQ3 (83 mm) and HQ (63.5 mm). The aim of this drilling campaign was to establish continuity of the pegmatite mineralisation at depth. Four boreholes, totalling 1,153 metres were surveyed in early 2017 by the new drilling contractor as only two of the six drill holes had been surveyed in 2011. Several of the holes had partly collapsed at depth.
The second diamond drilling programme, totalling 43 boreholes and 5,809 m of drilling, commenced in September 2016 and was completed by February 2017. The Zimbabwean company Geodrill from Bulawayo supplied and operated one and later two drill rigs on the project. 5,288 m of downhole surveys were completed for 40 drill holes with three holes not being surveyed due to drill hole collapses. Drill holes commenced with HQ (63.5 mm) diameter cores in the weathered zone and once in stable ground, the holes were completed with NQ (47 mm) coring.
The third diamond drilling programme commenced in 2021 and will continue through 2024. To date, 143 drill holes totalling 34,100.16 m have been completed. Drill holes are sited on a nominal 50 m x 50 m drill spacing. Holes are collared and drilled HQ size until the base of the weathered zone, cased and then completed with NQ-sized coring. Two drill contractors, supplying up to a six drill rigs, were deployed in 2022.
Sampling:
2016-2017 Drill Programme:
Drill cores were packed into metal core boxes which were secured on the drill site prior to being transported to the RHA Mine by truck. At the mine, the core was photographed and logged by Mr Wolfgang Hampel, the then Exploration Manager of Premier. Pegmatite intersections were marked-up, assigned unique sample numbers and cut in half, with one half subsequently being quartered. A diamond saw was utilised to cut the core. The quartered core was bagged for lithium and tantalum analysis, the balance of the core was stored at the RHA core shed, until transported to the new Zulu core shed in 2022. The lengths of the sampled cores varied between 0.16 m and 8.79 m, depending on the lithology (pegmatite / host rock) and the homogeneity of the pegmatites. Any identified zoned pegmatites were sampled across their logged mineralogical zones.
2021-2024 Drill Programme:
Drill cores are packed into metal core boxes at the drill site, with core block markers being inserted into the core boxes after each core run. Core is then transported to the Zulu core shed by company representatives. In the core shed, basic core measurements are captured (i.e. core recoveries and Rock Quality Designation - RQD). The core is then photographed and geologically logged. All pegmatite intersections, together with 1 m samples in the immediate hangingwall and footwall of the pegmatite, are marked up for cutting and sampling. The nominal sampling interval across a pegmatite intersection was 1 m but, in all cases, geological contacts were respected and no sampling across contacts took place. Unique sample numbers are assigned to each core sample. Core is cut in half and half cores were bagged and labelled. Bulk density determination on 10 cm lengths of core are then measured (Archimedes Principle) for each sample.
Samples are then transported under company supervision to Antec Laboratories in Kwekwe, for sample preparation.
Sample Analysis:
To date 10,129 core and trench sample assays have been returned. In addition, 1,528 QA/QC (Quality-Assurance / Quality-Control) samples (blanks, duplicates and standards), or 15.1% of the analysed core samples were inserted to ensure adequate QA/QC.
2016-2017 Drill Programme:
All sample preparation was carried out at RHA's sample preparation facility at the mine. Every sample of quarter core was dried, and its bulk density was determined using a density scale (Archimedes principle). Samples were crushed to -4 mm in a jaw crusher and a 200-250 g split was pulverised (minimum of 85% passing 75 microns (μm)). A 50 g aliquot of the pulverised samples was labelled and sent to SGS South Africa (Randfontein) for multi-element analysis (49 elements). SGS code ICM90A Multi Elements by sodium peroxide fusion, ICP-OES and ICP-MS finishes. The sodium peroxide fusion technique is considered to be a "total" dissolution technique for lithium-bearing silicate and tantalum bearing oxide minerals. Detection limits for lithium are 10 ppm to 10% (i.e. 100,000 ppm) and 0.5 ppm to 1% (i.e. 10,000 ppm) for tantalum. Certified Reference Material samples (AMIS0343) for lithium and tantalum were introduced into the sample stream at a rate of 1:16. Blanks were introduced at the same rate, the blank being sourced from a massive barren quartz vein found some 8 km from Zulu. A number of core samples from the earlier 2011 drilling campaign were re-assayed using the method described above. Initially, the samples of 2011 had only been dissolved using a multi-acid digestion, which is a semi-quantitative technique and not adequate to dissolve certain minerals including spodumene and tantalite.
2021-2024 Drill Programme:
Samples were prepared at Antec Laboratories in Zimbabwe. At Antec, samples were crushed to -2 mm then a 200 g aliquot was pulverised to a minimum specification of 85% passing 75 μm. Pulverised samples (pulps) were transported by an independent logistics company to the Premier offices in Johannesburg, where they were inspected and transported to SGS Lakefield by a company representative. SGS performed a sodium peroxide fusion with the 51 multi-element analytical finishes (ICP90A50 and IMS90A50). Detection limits for lithium are 10 ppm to 5% (50,000 ppm) and tantalum 0.5 ppm to 1% (10,000 ppm). QA/QC samples, (i.e. Certified Reference Material, blanks and duplicates) were inserted on site into the sample stream with each sample represented with a unique sample number. The QA/QC samples represent 15% of the total number of samples analysed.
Estimation Methodology:
3-dimensional geological modelling was conducted in Datamine Studio RM on a lithological basis by an external consultant, Shango. Information utilised to construct the models was sourced from 194 diamond drill boreholes, 31 trenches together with surface mapping. All data that was included within the models were verified and checked prior to modelling. At the time of model development assays from 163 boreholes were available. Wireframe models were constructed on lithological parameters as opposed to grade parameters. This method was imposed in order to remove the effect of holmquistite, which is a lithium bearing amphibole that is present in the host rock. Therefore, the wireframes constructed for the geological model only included mineralised pegmatites. Each of the 27 mineralised pegmatites was modelled separately and subsequently reviewed by Premier prior to the Mineral Resource estimation.
Each of the 27 mineralised pegmatites was flagged and estimated separately. The sample data were composited on a 1.5 m basis. For this exercise both Li2O and Ta2O5 were estimated. Statistical analyses were performed including descriptive statistics, histogram plots, probability plots and capping of outliers. Spatial variances were modelled in the form of downhole and planar variograms. Kriging neighbourhood analysis (KNA) determined the optimal block model cells sizes and search parameters for the estimation process. Ordinary Kriging (OK) was applied for the grade estimation and detailed model validations and checks were performed. Visual checks and various estimation parameters, including search volumes, number of samples, distance to samples, kriging efficiencies and regression slope, were utilised to classify the Mineral Resource into Indicated and Inferred categories.
Ongoing metallurgical test work indicated that spodumene accounts for more than 80% of the contained Li2O and the tonnages have been reduced to reflect only the contained Li2O that is associated with spodumene. Test work also indicated that all of the spodumene will be recovered and therefore a zero cut-off Li2O grade has been applied for the Mineral Resource statement. A zero cut off is considered applicable to this project as the Mineral Resource reflects the recovery of mineral (spodumene), as opposed to a metal. A further 5% geological loss has been applied for the Indicated category and 10% for the Inferred category.
Mineral Resource Classification:
Extensive close-spaced drilling allows that 60% of this MRE falls within the Indicated category. A combination of results from mining activities and further in-fill drilling is likely to see an increase in the Indicated category. Similarly, it is anticipated that the Mineral Resource classification will likely change to a Reserve classification with ongoing mining activity and grade control sampling, providing real time confirmation of the validity of the modifying factors that may be applied to the Mineral Reserve.
Mining and Metallurgy:
The Company has developed Zulu as an open pit mine. Plant and process design was based on metallurgical test work conducted by German based Dorfner-Anzaplan in 2016 and 2022 and is supported by extensive additional test work undertaken by Geolabs in South Africa and the laboratory established at Zulu in 2023.
Lithium (Li) is recovered from minerals such as spodumene, petalite and lepidolite as well as lithium-rich brines and is used in a range of products such as ceramics, glass, batteries and pharmaceuticals. Lithium use has expanded significantly in recent years due to the increasing use in rechargeable batteries in portable electronic devices and batteries and electrical motors for hybrid and electrical motor vehicles.
At Zulu, SC6 is the product recovered. Zulu will therefore report that the estimated tonnage of lithium is directly associated with spodumene. This assumes 100% recovery and no process losses in the concentration of spodumene in the plant are considered in this MRE.
Lithium standard conversion factors are set out in the Table 3 below:
Table 3: Conversion Factors for Lithium Compounds and Minerals
| Convert from | Convert Li | to Li 2 O | to Li 2 CO 3 | |
|---|---|---|---|---|
| Lithium | Li | 1.000 | 2.153 | 5.323 |
| Lithium Oxide | Li 2 O | 0.464 | 1.000 | 2.473 |
| Lithium Carbonate | Li 2 CO 3 | 0.188 | 0.404 | 1.000 |
The current pricing of Li is set out below (Source: Metal.Com):
- Spodumene concentrate, SC6 6% Li 2 O, CIF China US$950/t.
- Spodumene concentrate, >7% Li 2 O, CIF China: US$1,610/t.
Li content of pure Spodumene concentrate is 8.03%.
Tantalum
The primary source of tantalum is from minerals including tantalite, columbite, wodginite and microlite which are typically hosted in pegmatite ore bodies. The largest deposits are located in Australia, Brazil and Africa. Tantalum's major use is in the production of electronic components, especially for capacitors, with additional use in components for chemical plants, nuclear power plants, airplanes and missiles. It is also used as a substitute for platinum.
The tantalum market is niche in size with around 1,300 tonnes required each year. However, the market is rapidly growing due to capacitor use in wireless and handheld devices.
Withdrawal of Previous Mineral Resource Estimate and declaration:
Premier has withdrawn the previous MRE related to Zulu published in 2017 and which has been superseded by the MRE set out in this announcement and in particular:
- The estimation methodology in the 2017 MRE, whilst appropriate at that time based on the very limited and widely spaced data and early stage of exploration, is superseded by the extensive data set now available to Zulu; and
- Industry Standard reporting has generally disregarded mineral assemblage in reporting lithium grade only. Zulu is concerned with the recovery and production of spodumene only and Shango Solutions considers the reporting of overall lithium grade, without reference to mineral assemblage as unsuitable for this project.
Mineral Resource Estimate
The scientific and technical information contained in this announcement that relates to the Mineral Resource Estimate is based on data compiled and verified by Mr Charles Muller of Shango Solutions, including the sampling, preparation, security and analytical procedures.
Shango Solutions has reviewed the information in this announcement that relates to the Mineral Resource Estimate and has confirmed that the information presented is balanced and complete and not inconsistent with the reported MRE.
Mr Charles Muller is a Competent Person who is a Professional Natural Scientist registered with the South African Council for Natural Scientific Professions (No. 400201/04) and a Fellow of the Geological Society of South Africa, each of which is a "Recognised Professional Organisation" (RPO). Mr Charles Muller has sufficient experience that is relevant to the style of mineralisation and type of deposit under consideration and to the activity being undertaken to qualify as a Competent Person as defined in the 2014 Edition of the "South African Code for the Reporting of Mineral Resources and Mineral Reserves". Mr Charles Muller consents to the release of the report and the information contained therein.
Mr Charles Muller is an employee of Shango Solutions (Shango), registered as Dunrose Trading 186 (Pty) Ltd and established in April 2004. Shango provides a diverse range of services to the mineral and mining sectors. Areas of specialisation include target generation, exploration, geodatabase compilation and management, geological modelling, resource estimation, mineral asset valuations, due diligences, desktop project reviews and technical reporting.
Mr Charles Muller provides independent technical geological services to Premier. Furthermore, Mr Muller has extensive experience in preparing technical and competent persons' reports for exploration and mining companies.
Mr Charles Muller is not employed by or related to any employees, representatives or directors of Premier Minerals. In addition, neither Shango nor its employees have or have had any personal interest in this project resulting in a conflict of interest.
Geology
Bruce Cumming, a consulting geologist to Premier, has reviewed and approved this release to the extent that reference is made to the geology and mineralogy of the Zulu pegmatites. Mr. Cumming is a SACNASP and GSSA registered geoscientist with 48 years' experience in exploration and project management, in multicommodity projects throughout Africa.
Market Abuse Regulations:
The person who arranged the release of this announcement on behalf of the Company was George Roach.
A copy of this announcement is available at the Company's website, www.premierafricanminerals.com
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