22 April 2024
First Tin Plc
("First Tin" or "the Company")
Tellerhäuser Mineral Resource Estimation Update
First Tin PLC ("First Tin"), a tin development company with advanced, low capex projects in Germany and Australia, is pleased to announce an updated Mineral Resource Estimate ("MRE") for its 100% owned Tellerhäuser Tin Project in Germany, completed by independent geological consultants DMT Group ("DMT"). The MRE has been prepared in accordance with the 2012 JORC Code & Guidelines and based on the additional information obtained from archives in Hartenstein and Chemnitz.
Highlights:
· Total Indicated plus Inferred tin Mineral Resource Estimate ("MRE") at 0.20% Sn cut-off has increased by 35% from the H&S Consultants Pty Ltd ("H&SC") 2019 estimate, from 102,900t tin to 138,600t tin.
· Total Indicated only tin MRE at 0.20% Sn cut-off has increased from the H&SC estimate by 37% from 32,700t tin to 45,000t tin.
· Additional 42,726 tin assays included in the database, of which 1,164 are above the cut-off grade.
· Cut-off has been reduced from 0.50% Sn to 0.20% Sn due to improved tin prices. At the previously reported 0.50% cut-off grade, there is a 49% increase in Indicated and Inferred tin MRE from the previous Bara estimate 2021, which was quoted in the IPO prospectus.
· The additional MRE tonnage in the Indicated category, obtained by a combination of lower cut-off grade and increased data density, will enable a longer mine life to be considered in economic evaluations.
First Tin's CEO, Bill Scotting, commented: "This increased MRE is a large step forward for us at our Tellerhäuser project in Germany. In a world requiring more tin, but with few advanced projects such as ours, increasing our resources from historic drilling data mining is extremely valuable. The additional data from the equivalent of 1311 drillholes and channel samples has enabled a more robust resource model with significantly more tonnes. The increase in tonnage, especially in the Indicated category, allows us to consider a longer mine life in economic evaluations."
The updated Mineral Resource Estimate (MRE) is:
Table 1. Tellerhäuser Indicated and Inferred resource
| Resource Class | Domain | Density [t/m³] | Volume [Mm³] | Tonnage [Mt] | Sn [%] | Sn [t] | Fe₂O₃ [%] | Zn [%] | Ag [ppm] | In [ppm] |
|
Indicated | Skarn | 3.60 | 1.44 | 5.18 | 0.57 | 29,700 | 17.94 | 0.78 | 3.92 | 40.17 |
| Mineralised Schist | 2.90 | 1.65 | 4.79 | 0.32 | 15,300 | 1.92 | 0.04 | 0.94 | 3.39 | |
| Total Indicated | 3.26 | 3.09 | 9.97 | 0.45 | 45,000 | 10.24 | 0.42 | 2.49 | 22.49 | |
|
Inferred | Skarn | 3.60 | 3.17 | 11.42 | 0.65 | 74,000 | 12.25 | 0.96 | 3.67 | 41.77 |
| Mineralised Schist | 2.90 | 2.26 | 6.55 | 0.30 | 19,600 | 2.33 | 0.03 | 0.71 | 1.09 | |
| Total Inferred | 3.34 | 5.43 | 17.97 | 0.52 | 93,600 | 8.63 | 0.62 | 2.59 | 26.94 |
The estimation was made by Florian Lowicki and Dr Bernd Teigler of DMT who are both Competent Persons under the JORC 2012 code and consent to the reporting of the MRE in the form and context in which it appears here. The JORC Table 1 is appended to the end of this announcement.
The MRE is reported to a 0.2% Sn cut-off grade which corresponds to an average resource grade of around 0.5% Sn. This is considered by the consultants to be a reasonable cut-off based on current tin prices.
A comparison with previous estimates is shown in the table below. Note that GKZ 1991 is a manual estimate and uses a 0.15% Sn cut-off. The rest are geostatistical estimates and use a cut-off of 0.20% Sn.
Table 2. Tellerhäuser Indicated and Inferred resource comparison (0.20% Sn cut-off)
| Estimated By | Resource Category | Tonnes (M) | Grade (% Sn) | Tin (Tonnes) |
| GKZ 1991 | Indicated | 8.95 | 0.47 | 42,400 |
|
| Inferred | 13.67 | 0.57 | 78,500 |
|
| Total | 22.62 | 0.53 | 120,900 |
| H&SC 2019 | Indicated | 6.87 | 0.48 | 32,700 |
|
| Inferred | 15.24 | 0.46 | 70,200 |
|
| Total | 22.11 | 0.47 | 102,900 |
| DMT 2024 | Indicated | 9.97 | 0.45 | 45,000 |
|
| Inferred | 17.97 | 0.52 | 93,600 |
|
| Total | 27.93 | 0.50 | 138,600 |
The total MRE conducted by DMT contains around 36,000t (35%) more tin than the H&SC MRE and around 12,000t (37%) more tin in the Indicated category. This is partly due to using a higher bulk density (based on many new measurements obtained from the archives) and on using a slightly larger search radius.
A direct comparison with the Bara MRE, which used a cut-off of 0.50% Sn, and re-stating of the DMT MRE at 0.50% Sn cut-off, is provided below for completeness.
| Estimated By | Resource Category | Tonnes (M) | Grade (% Sn) | Tin (Tonnes) |
| Bara 2021 | Indicated | 2.0 | 1.0 | 19,000 |
|
| Inferred | 3.3 | 1.0 | 34,000 |
|
| Total | 5.3 | 1.0 | 53,000 |
| DMT 2024 | Indicated | 2.3 | 1.0 | 23,000 |
|
| Inferred | 4.9 | 1.2 | 56,000 |
|
| Total | 7.2 | 1.1 | 79,000 |
At 0.50% cut-off grade, the total DMT MRE contains around 26,000t (49%) more tin than the Bara MRE and around 4,000t (21%) more tin in the Indicated category.
The updated MRE is based on the digitisation of the large amount of additional historic drilling data discovered in the archives in Hartenstein and Chemnitz. This data, previously obtained by Wismut during the 1970s and early 1980s, closes existing gaps in the mineral resource and provides additional resource volume, at minimal additional cost. An additional 42,726 tin assays have been included in the database, with 1,164 of these reporting grades over the cut-off of 0.20% Sn.
The following figures show a 3D model of the deposit and a grade-tonnage graph for Indicated category mineralisation.
The Tellerhäuser project is owned by First Tin's 100% owned German subsidiary, Saxore Bergbau GmbH.
Enquiries:
| First Tin | Via SEC Newgate below |
| Bill Scotting - Chief Executive Officer |
|
| Arlington Group Asset Management Limited (Financial Advisor and Joint Broker)
| |
| Simon Catt | 020 7389 5016 |
| | |
| WH Ireland Limited (Joint Broker) | |
| Harry Ansell | 020 7220 1670 |
| | |
| SEC Newgate (Financial Communications) | |
| Elisabeth Cowell / Molly Gretton | FirstTin@secnewgate.co.uk |
Notes to Editors
First Tin is an ethical, reliable, and sustainable tin production company led by a team of renowned tin specialists. The Company is focused on becoming a tin supplier in conflict-free, low political risk jurisdictions through the rapid development of high value, low capex tin assets in Germany and Australia, which have been de-risked significantly, with extensive work undertaken to date.
Tin is a critical metal, vital in any plan to decarbonise and electrify the world, yet Europe has very little supply. Rising demand, together with shortages, is expected to lead tin to experience sustained deficit markets for the foreseeable future.
First Tin's goal is to use best-in-class environmental standards to bring two tin mines into production in three years, providing provenance of supply to support the current global clean energy and technological revolutions.
APPENDIX 1 - JORC CODE, 2012 EDITION - TABLE 1 MINERAL RESOURCE ESTIMATION - UPDATE FOR THE TELLERHÄUSER PROJECT AREA, SAXONY, GERMANY.
| Section 1 Sampling Techniques and Data (Criteria in this section apply to all succeeding sections.) | ||
| Criteria | JORC Code explanation | Commentary |
| Sampling techniques | · Nature and quality of sampling (eg cut channels, random chips, or specific specialised industry standard measurement tools appropriate to the minerals under investigation, such as down hole gamma sondes, or handheld XRF instruments, etc). These examples should not be taken as limiting the broad meaning of sampling. · Include reference to measures taken to ensure sample representivity and the appropriate calibration of any measurement tools or systems used. · Aspects of the determination of mineralisation that are Material to the Public Report. · In cases where 'industry standard' work has been done this would be relatively simple (eg 'reverse circulation drilling was used to obtain 1 m samples from which 3 kg was pulverised to produce a 30 g charge for fire assay'). In other cases more explanation may be required, such as where there is coarse gold that has inherent sampling problems. Unusual commodities or mineralisation types (eg submarine nodules) may warrant disclosure of detailed information.
| · While the bulk of the data is from exploration work completed in the 1970s and 1980s by state-owned Wismut company, Saxore completed since 2013 a confirmation channel sampling, a bulk sampling program in Hämmerlein and a confirmation drilling program at Dreiberg. Historic Sampling: · The historic sampling is based on diamond core drilling, and channel sampling where the underground exploration drifts did cut mineralisation and drilling was not possible. · Sampling was done based on standardized operating procedures following the standards at that time. · Channel sampling was done using an angle grinder to cut two 2cm deep cuts 10 cm apart with the material between the two cuts removed with a compressed air jackhammer. · Drill core was logged and marked up for sampling under geological control with 1 m being the dominant sample interval and thereafter, core was split into halves using a core splitter. One half was stored for further geological, mineralogical, and processing investigations and the other half was used for further sample preparation and analysis. · The half-core sample was crushed in 2 steps. In the first step, the sample was crushed with a double-toggle jaw crusher to 100 % passing 10 mm. A single-toggle jaw crusher was then used to crush the entire sample to below 1 mm. After homogenization, the sample was divided until a representative 400 g subsample was achieved. This sample was milled to a powder in the last stage by using a vibratory disc mill. The resulting 400 g sample had to fulfil the requirement of 95 % <65 μm. This was tested internally as well as by external controls. From this final 400 g sample, all sub-samples for different analysis. Confirmation Sampling (Saxore): · From 2013 onwards, Saxore collected and assayed a variety of samples as part of the project development. In 2015, Saxore executed a targeted sampling programme comprising 66 channel samples from accessible areas in Hämmerlein. A total of approx. 2.2 t of material was taken. Samples were subjected to a variety of bench-scale tests including sorting, dense media separation, magnetic separation, flotation, and gravity. · The channels were cut using an electric rock saw and jackhammer and were mainly cut V-shaped approximately 10-15 cm wide and max. 11 cm deep. The material was then chiselled out using the jackhammer. · Diamond drilling was used to obtain 1 m samples, depending on the lithology of HQ core which was sawn in half longitudinally. The half core was bagged and sent to ALS Global for assaying. This is industry standard work. · No samples from Reverse Circulation (RC) drilling were used · All core samples intersected the main Dreiberg skarn were sent for assay after being logged by the geologist. · All drilling samples of the main skarn and intervals approximately 10 to 20m above and below the skarn were analysed. |
| Drilling techniques | · Drill type (eg core, reverse circulation, open-hole hammer, rotary air blast, auger, Bangka, sonic, etc) and details (eg core diameter, triple or standard tube, depth of diamond tails, face-sampling bit or other type, whether core is oriented and if so, by what method, etc). | Historic Drilling: · Four main phases of drilling have been undertaken from 1966 to 1991 from surface and underground · All drill-core was 56mm in diameter (between NQ and HQ) but for areas of difficult ground bigger core sizes were used. There is no indication of how much difficult ground was encountered. The 1970-75 drilling used an SBU SIF-650 surface rig (rated to 1000m) and a SIF-300 and SIF-650 underground rigs. Downhole geophysics was completed for the surface holes and most of the underground holes but no digital data is available. The 1976-1981 underground drilling campaign used a GP-1 and BSK-2m-100 drilling rigs. Confirmation Drilling: · The primary aims were to confirm historic grades and upgrade parts of the inferred resource to the next higher category in accordance with the JORC Code (2012) by expanding the data base in the thick skarn seams. Between 20 August 2022 and 23 April 2023, surface drilling was carried out. The project was coordinated by Saxore and the drilling work was carried out by GEOPS Bohrgesellschaft mbH and later by Pruy KG, Gesteins-, Bohr- und Umwelt-Technik. · Diamond drilling was undertaken by the contractor GEOPS Bohrgesellschaft mbH. All drilling used PQ or HQ bits. Directional drilling was done in NQ which was redrilled in HQ. Drill rods were stabilized and triple tubing was used to ensure good core recovery and avoid washing out of cassiterite. · Drilling was at an angle of -69° to-79° and hence cuts across the skarn seams that are sub-horizontal. · GEOPS Bohrgesellschaft mbH used drilling rigs from Atlas Copco Crealius. The drilling by Pruy KG was carried out with a HD 110 coring drilling rig mounted on a crawler. A total of 8 drill holes with a total length of 4365.7 m were drilled from 3 drill sites (including three test holes from Pruy from collar SaxDRE036). · The holes drilled by GEOPS Bohrgesellschaft mbH in the period from 20 August 2022 to 30 December 2022 were cored. Drilling without coring was performed at the top, where a standpipe was drilled and in sections where directional drilling was carried out to reach the target (downhole motor). Drill holes started with PQ diameter and changed to HQ at a certain depth. NQ for pre-drilling was necessary for directional drilling in some parts. · Drilling by Pruy KG in the period from 15 April 2023 to 22 April 2023 was carried out using a RC method, whereby the rock is crushed at the bottom of the hole and transported to the surface by compressed air in an inner tube and thus preventing contamination. Systematic sampling did not take place. · All drilling, depth control and recovery was supervised by project geologists |
| Drill sample recovery | · Method of recording and assessing core and chip sample recoveries and results assessed. · Measures taken to maximise sample recovery and ensure representative nature of the samples. · Whether a relationship exists between sample recovery and grade and whether sample bias may have occurred due to preferential loss/gain of fine/coarse material. | Historic Drilling: · Recovery data was supplied as a decimal fraction of the measured length which HSC converted to a percentage. The data contained recoveries for both channel sampling and diamond drilling. HSC reviewed recoveries for the three mineral zones only, primarily to establish if there was any bias with either the sampling methods or with the tin grades. In all instances average recovery was greater than 97% with 98.5%, 97.6% and 97.3 % for Hämmerlein, Dreiberg and Zweibach respectively. No bias with either the sampling method or the tin grade was observed. Confirmation Drilling: · All core intervals are measured and compared with driller's marks to determine actual recovery. Recovery was generally above 95% apart from isolated intervals with poor ground conditions, generally either near surface or in fault zones. During directional drilling no core or cuttings could be sampled. The loss for these areas was 100%. · No systematic core loss in mineralised zones was noted. · During coring, core recovery in fresh rock was generally above 95 %, with the exception of disturbed or brecciated areas. During directional drilling no core or cuttings could be sampled. The loss for these areas was 100 %. It was agreed with the drill contractor that directional drilling would no longer be used 100 metres above the target depth. No systematic core loss was detected. |
| Logging | · Whether core and chip samples have been geologically and geotechnically logged to a level of detail to support appropriate Mineral Resource estimation, mining studies and metallurgical studies. · Whether logging is qualitative or quantitative in nature. Core (or costean, channel, etc) photography. · The total length and percentage of the relevant intersections logged. | Historic · Logging consisted of hand-written detailed hardcopy log sheets completed by Wismut that have been transcribed into digital data by Beak Consultants (based in Freiberg, Germany). This included using numeric codes for the different lithotypes (Appendix 2). The quality of the logging is good and includes the added bonus of graphic logs. · The main items have all been captured in the digital database including the drill intervals, lithology, recovery and assay data. · The captured data has been compared with original drill logs by Saxore for much of the database, as part of a manual resource estimation. Only minor errors were noted and no significant problems were found in the data checked. · Validation of the drillhole database by HSC included reviewing of 50 randomly selected hardcopy drillogs for the three areas and comparing numbers etc for downhole surveys, geological logging and assays. No significant issues were noted. · No core remains available for viewing. All core was destroyed with the cessation of the uranium mining. Confirmation: · All diamond drill cores have been geologically logged and photographed (wet and dry) to a level of detail to support appropriate mineral estimation, mining, and metallurgical studies. · A logging of RC cuttings was omitted as no mineralisation was expected in the near surface area of the planned RC hole. |
| Sub-sampling techniques and sample preparation | · If core, whether cut or sawn and whether quarter, half or all core taken. · If non-core, whether riffled, tube sampled, rotary split, etc and whether sampled wet or dry. · For all sample types, the nature, quality and appropriateness of the sample preparation technique. · Quality control procedures adopted for all sub-sampling stages to maximise representivity of samples. · Measures taken to ensure that the sampling is representative of the in situ material collected, including for instance results for field duplicate/second-half sampling. · Whether sample sizes are appropriate to the grain size of the material being sampled. | Historic: · Assaying of Sn was carried out using the device "MAK-1" (until 1974) and "Romul-EFA" (from 1974). Assays of MAK and EFA were performed on site using a 5 g split of the sample collected as described above. · The MAK-1 device ('Mössbauer-Analysator für Kassiterit': Mössbauer analyzer for cassiterite, which is a Gamma-ray fluorescence analyzer) only determines the content of oxidic Sn, as this device does not detect Sn in silicate minerals and others (e.g., stanine). These values were recorded in the database in the column "Sn_pc_MAK". · The "Romul-EFA" device ('Element Fluoreszenz Analyzer', which is an X-ray fluorescence analyzer) measures the total Sn content with its two-channel elemental phase analyzer, regardless of its mineralogy. These values were recorded in the database in the column "Sn_pc_EFA". · MAK and EFA was carried out on a 5 g chip sample at the mine site in the laboratory in Pöhla. This was followed by spectral analysis (AES) of all samples for the elements Zn, Pb, Cu, In, Cd, As, W, Ag, As and Bi, whereby the prioritization of the elements to be analyzed varied and changed over time. Elements such as B, Ni, Co, but also F, P, Mn, Zr, V, Cr, Sr, Ge, Nb, Ta, Sb, Se, Ga, Au, Y, La and Ce were also analyzed spectroscopically over time and ranges. If the upper detection limit was overrated, X-ray fluorescence analyses were performed for the elements Zn, Pb, Cu, As, W, Bi and Cd. If the upper detection limit for the elements Cu and In was exceeded, further atomic absorption spectrometric analyses (AAS) was carried out. · Iron and zinc were analyzed using FAAS, with total iron reported as Fe2O3. DMT notes that total iron includes Fe hosted by all Fe-bearing minerals reported in the skarn mineralogy including magnetite, amphiboles, garnets, chlorite and Fe-rich sphalerite, etc. Confirmation: · The drill core samples were sent to certified ALS Laboratory in Rosia Montana, Romania. · At the ALS laboratory in Rosia Montana, the sample of core is crushed and split to around 1kg to finer than 2 mm using method CRU-31, then pulverized in a mill to 85% finer than 75µm using method PUL-32. · Analysis of the diamond drill samples consisted of a four-acid digest and ICP-AES for 33 elements. The samples were also assayed for Sn and In using a lithium borate fusion and ICP-MS technique. If over detection limits on the ICP was reached, then the samples were assayed using XRF. |
| Quality of assay data and laboratory tests | · The nature, quality and appropriateness of the assaying and laboratory procedures used and whether the technique is considered partial or total. · For geophysical tools, spectrometers, handheld XRF instruments, etc, the parameters used in determining the analysis including instrument make and model, reading times, calibrations factors applied and their derivation, etc. · Nature of quality control procedures adopted (eg standards, blanks, duplicates, external laboratory checks) and whether acceptable levels of accuracy (ie lack of bias) and precision have been established. | Historic: · The devices of EFA and MAK were tested under certain circumstances on samples of the Tellerhäuser deposit and fulfilled the requirements considering accuracy, sensibility, stability, reliability, and speed. The technique appears to be very accurate up to 10% Sn but this is the maximum value it can usefully detect, with anything over 10% Sn being reported as simply >10% Sn. · In order to control EFA and MAK an additional 5 g split of the original 400 g pulverised sample was collected at regular intervals (approximately 1 in 10) and sent to an external laboratory, Grüna (Central laboratory of SDAG Wismut) where it was analysed by a wet chemical method. The working routine was started with an alkali fusion with Na2O2/NaOH fluxing reagent (sample/reagent = 1/10). Leaching was undertaken with distilled water and neutralized with HCl. Three grams of aluminium were added to this solution to create reducing conditions. Small grains of calcite were added to ensure the production of CO2 and thus prevent the influence from oxygen in the air. This tin solution then underwent a titration process with iodine utilizing the reaction Sn2+ + I2 → Sn4+ + 2 I. By adding small drops of 0.1 molar iodine solution to the dissolved sample, an abrupt colour change from transparent to blue appears at a certain level of added iodine. Each 1 ml of added reagent corresponds to 0.5935 mg Sn in the sample. By using the simple rule of proportion, the tin grade of the original sample was thus calculated. These values were recorded in the database in the column "Sn_pc_Chemie". · An additional 5 g split of the original 400 g sample was collected at regular intervals and sent to a third laboratory as a check for the three techniques described above. This was undertaken in the laboratory of the Ehrenfriedersdorf tin mine and used the same assay technique as the Grüna Laboratory (Central laboratory of SDAG Wismut), as described above. · Assaying was checked by internal and external control analyses. The measuring devices in the laboratories were calibrated daily. Calibration was performed as standard on the basis of various defined content classes. · Within the sample batches, a minimum of 1 standard per 20 samples was prescribed, but the rule was 1 in 10. These standards were made from different materials of different content classes and had different qualities in order to check the accuracy. The standard measurements were recorded in the laboratory and kept in the archive. Only the sample results were communicated to the client (SDAG Wismut laboratory order). Confirmation: · Tin is a difficult element to analyse as cassiterite is not soluble in acid. Thus, a sub-sample of the pulverized and mixed material is taken and fused with lithium borate. The fused bead is then analysed by a mass spectrometer using method ME-MS85 which reports Sn and In. This returns a total tin content, including tin as cassiterite. Over limit assays of tin are re-analysed using method ME-XRF15b which involves fusion with lithium metaborate with a lithium tetraborate flux containing 20% NaNO3 with an XRF finish. · Other elements are analysed by method ME-ICP61. This involves a 4 acid (HF-HNO3-HCLO4 digest, HCl leach and ICP-AES finish). This is an industry standard technique for Cu, Pb, Zn and Ag. A suite of 33 elements is reported, including tin, which is only acid soluble tin in this case and thus can be subtracted from the fusion tin assays to obtain tin as cassiterite. The acid soluble tin is generally associated within the lattice of silicates and Fe-oxides. It is in some part significant as it has a main impact on tin recovery. · Prior to dispatch of samples, the following QA/QC samples are added: · Certified standards representative of the grades expected are added at the rate of 1 in 20 samples. · Blanks are added at the rate of 1 in 20 samples. |
| Verification of sampling and assaying | · The verification of significant intersections by either independent or alternative company personnel. · The use of twinned holes. · Documentation of primary data, data entry procedures, data verification, data storage (physical and electronic) protocols. · Discuss any adjustment to assay data. | Historic: · Due to the privatization of the laboratories in the 1990s, a large part of the archive data was destroyed. As a result, there is hardly any information about the standards used and the control analyses determined. But corresponding results of the control analyses and error estimates are documented in the report. Confirmation: · Twinning of the previous Wismut drill hole S21 show acceptable reproduction in hole SaxDRE034. · Results of Certified Reference Materials for Sn show acceptable reproduction of certified values. Thus, analysis method is assessed as appropriate to have produced reliable results on a level of confidence required for resource estimation · Results of Blanks for Sn demonstrate that a cross-contamination during sample preparation and analysis is not observed. · Internal quality control by ALS included the following additional analyses: CRMs for each analytical method, blanks and duplicate measurements of the drill core samples submitted. Blanks: all analysed internal blanks had values of <0.5 ppm Sn. Duplicates: all showed very good agreement for the different analytical methods as shown in the following plots. |
| Location of data points | · Accuracy and quality of surveys used to locate drill holes (collar and down-hole surveys), trenches, mine workings and other locations used in Mineral Resource estimation. · Specification of the grid system used. · Quality and adequacy of topographic control. | · All location information is in metric projected coordinate reference system UTM ETRS89 Zone 33N as measured or transformed from historic reference systems by Saxore. Historic: · In the 1976 to 1981 drilling campaign, drill collars were surveyed in using a closed loop theodolite method tied in to the national grid. It is uncertain if this method was used for the earlier or later drilling campaigns. · Downhole surveys for the early drilling were measured using a Multigraph Inclinometer at 10 to 25m intervals. This apparatus had an accuracy of 0.5° for the dip angle and 3° for the azimuth. The final phase of drilling saw the use of camera surveys although no details are known. All survey data in the database were generated by using detailed surveyed points in hardcopy level plans, which show accurate collar, downhole survey and end of hole locations and RL (height above mean sea level) for each of these points. Confirmation: · All drill holes are pre-planned and located by use of a handheld GPS. Holes were originally sited and angled using compass and clinometer. Prior drilling, hole collars were surveyed with tachymeter from accurately surveyed official fixed-points due to the lack of GPS signal and mobile connection. This was changed to the use of Devico gyro navigation for the later downhole survey in order to get an added level of accuracy. · GEOPS carried out down-hole orientation surveys with measurements at 25 m intervals, while Pruy KG measurement spacing was approx. 50 m.
|
| Data spacing and distribution | · Data spacing for reporting of Exploration Results. · Whether the data spacing and distribution is sufficient to establish the degree of geological and grade continuity appropriate for the Mineral Resource and Ore Reserve estimation procedure(s) and classifications applied. · Whether sample compositing has been applied. | Historic: · Drilling was done from 50 m spaced drifts in 10 m distanced stations, each station having 1 to 3 holes drilled as fan to the mineralization below or above the drift plus 5 m spaced channels when the drift is intersecting the mineralisation · Predominant sample length is 1 m for both the drilling and channels · The data spacing and distribution is sufficient to establish and suitably classify Mineral Resource Estimates. · For Sn a sufficient amount and density of data was available in Hämmerlein to produce variograms in acceptable quality for the domain of Skarn and Mineralised Schist. Thus, the resulting parameters were used to interpolate Sn in domains of Skarn and Mineralized Schist using OK for all the areas of Tellerhäuser project area. · For Fe2O3, Zn, Ag, Cu, WO3, In, Bi, Ge, As, Cd IDW was applied due to limited amount and distribution of these assays. · Around 6 % (holes) and 3 % (channels) of sample intervals are above 1 m. Thus, a sample compositing is assumed. Confirmation: · The original drilling undertaken was intended to be better than a 50m x 50m spacing. · Twin drilling was used to verify the historical drilling, check its geological units and verify the geochemical results. · The original data spacing is considered to be sufficient to establish the degree of geological and grade continuity appropriate for the JORC classifications applied. |
| Orientation of data in relation to geological structure | · Whether the orientation of sampling achieves unbiased sampling of possible structures and the extent to which this is known, considering the deposit type. · If the relationship between the drilling orientation and the orientation of key mineralised structures is considered to have introduced a sampling bias, this should be assessed and reported if material. | Historic: · The drill orientation is approximately perpendicular to mineralized skarn units and does not appear to introduce bias. · The schist mineralisation at Hammerlein has both a sub-vertical and sub-horizontal component and hence the mainly sub-vertical drilling may not be optimal for some of the sub-vertical structures.
Confirmation: · No orientated drilling was carried out. · The skarn seams are sub-horizontal and the drilling is angled at between -69° and -79° to be as close as possible to cutting across the skarn seams at 90°. · As drilling was designed to intersect the main skarn seams at as high an angle as possible. The potential for any introduced sampling bias is considered minor. |
| Sample security | · The measures taken to ensure sample security. | Historic: · This was an active uranium mining area during GDR times and security was thus very tight. No reason to suspect any security issues can be found. Confirmation: · All core and sample material was stored and investigated in a locked facility. All transportation was done by authorized personnel only. Sample transportation was cross-checked by sample list completeness of amount of samples and sample weight. |
| Audits or reviews | · The results of any audits or reviews of sampling techniques and data. | Historic: · Audits and reviews were conducted at regular intervals during the GDR era but results are not currently available. The GDR era estimates are classified between C1 and Delta category which require audits by the central authorities. · Audits and reviews have been done by HSC in 2019, BARA in 2021 · The techniques of sampling, QA/QC methods and quality of the historic data was assessed as appropriate to be used for resource estimation |
| Section 2 Reporting of Exploration Results (Criteria listed in the preceding section also apply to this section) | ||
| Criteria | JORC Code explanation | Commentary |
| Mineral tenement and land tenure status | · Type, reference name/number, location and ownership including agreements or material issues with third parties such as joint ventures, partnerships, overriding royalties, native title interests, historical sites, wilderness or national park and environmental settings. · The security of the tenure held at the time of reporting along with any known impediments to obtaining a licence to operate in the area. | · First Tin, via its 100% owned subsidiary Saxore, holds a valid Mining Licence (ML) for the extraction of mineral resources for the "Rittersgrün" field which contains the Tellerhäuser Project, consisting of the Hämmerlein and Dreiberg resources. The mining licence was issued in compliance with the German Federal Mining Act and is valid until the 30th June 2070. · The mineralisation is secured by the Breitenbrunn Erlaubnis (exploration permit). It is 100% owned by Saxore Bergbau GmbH. This licence is valid for Sn, W, Mo, Ta, Be, Cu, Pb, Zn, Ag, Au, Ge, In Fe, Fluorite and Baryte. · A pre-existing Bewilligung (mining permit) exists over radioactive minerals but this is owned by Wismut GmbH, a Federal Government company tasked with clean-up of previous uranium mining activities which is not allowed to undertake any mining activities. It is currently only treating water run-off from the old mine. · The area is in a region of spruce and mixed forests. The environment has been effected in the past by previous mining activities. No immediate environmental impediments are obvious other than the disturbance caused by vehicle movement on surface and initial development from surface. |
| Exploration done by other parties | · Acknowledgment and appraisal of exploration by other parties. | · Significant work was undertaken by a Soviet - East German joint venture and these activities for the basis of the current resource estimate. No other activities are known in the project area. |
| Geology | · Deposit type, geological setting and style of mineralisation. | · The mineralisation consists of skarn, overprinted skarn, and schist hosted sub-vertical and sub-horizontal greisen veins. It is hosted within Cambrian to Ordovician meta-sediments intruded by Carboniferous to Permian aged granites. Metamorphism is generally under greenschist to amphibolite facies conditions. The granites are generally accepted as the source of the tin mineralising fluids which have subsequently deposited tin and other associated elements in chemically and structurally favourable settings when pressure, temperature and physico-chemical conditions were optimal. In particular, originally calcareous beds have acted as a very good chemical trap for the ascending tin rich fluids, being metasomatised to a skarn assemblage. However, a significant, later, retrograde event associated with chlorite minerals, has deposited a significant amount of coarse cassiterite (SnO2) and hence the deposit is not a "typical" skarn tin deposit. · The overprinted skarn are sub-horizontal zones between 1m and 15m true thickness (averaging about 3m) that are several hundred metres wide and several thousand metres long. These consist of amphibole, garnet, pyroxene, feldspar, magnetite, cassiterite, sphalerite and other sulphides. These have been subsequently partially metasomatised under retrograde conditions which has resulted in chloritic alteration fronts with coarse quartz-cassiterite segregations and veins. Cassiterite has been deposited in both the prograde and retrograde metasomatic events and occurs in both coarse and fine grained (less than 50 micrometres) forms. · These seams are very continuous geologically and can be traced over several kilometres. However, several generations of mineralisation are evident and the paragenesis is complex. Faulting and parting also effects the skarn units. · The Hämmerlein skarn has associated schist hosted greisen style mineralisation that occurs as both sub-vertical and sub-horizontal quartz-feldspar-tourmaline-cassiterite veins immediately below the main skarn unit. These form a sheeted to stockwork vein array which has been located up to 30m below the main skarn and is open at depth. It is suspected that this zone may have significant depth potential due to its partially sub-vertical disposition but has not been adequately drill tested below about 30m beneath the Hämmerlein Seam. |
| Drill hole Information | · A summary of all information material to the understanding of the exploration results including a tabulation of the following information for all Material drill holes: o easting and northing of the drill hole collar o elevation or RL (Reduced Level - elevation above sea level in metres) of the drill hole collar o dip and azimuth of the hole o down hole length and interception depth o hole length. · If the exclusion of this information is justified on the basis that the information is not Material and this exclusion does not detract from the understanding of the report, the Competent Person should clearly explain why this is the case. | · This project is resource status, not exploration status |
| Data aggregation methods | · In reporting Exploration Results, weighting averaging techniques, maximum and/or minimum grade truncations (eg cutting of high grades) and cut-off grades are usually Material and should be stated. · Where aggregate intercepts incorporate short lengths of high grade results and longer lengths of low grade results, the procedure used for such aggregation should be stated and some typical examples of such aggregations should be shown in detail. · The assumptions used for any reporting of metal equivalent values should be clearly stated. | · This project is resource status, not exploration status |
| Relationship between mineralisation widths and intercept lengths | · These relationships are particularly important in the reporting of Exploration Results. · If the geometry of the mineralisation with respect to the drill hole angle is known, its nature should be reported. · If it is not known and only the down hole lengths are reported, there should be a clear statement to this effect (eg 'down hole length, true width not known'). | · This project is resource status, not exploration status |
| Diagrams | · Appropriate maps and sections (with scales) and tabulations of intercepts should be included for any significant discovery being reported These should include, but not be limited to a plan view of drill hole collar locations and appropriate sectional views. | · This project is resource status, not exploration status |
| Balanced reporting | · Where comprehensive reporting of all Exploration Results is not practicable, representative reporting of both low and high grades and/or widths should be practiced to avoid misleading reporting of Exploration Results. | · This project is resource status, not exploration status |
| Other substantive exploration data | · Other exploration data, if meaningful and material, should be reported including (but not limited to): geological observations; geophysical survey results; geochemical survey results; bulk samples - size and method of treatment; metallurgical test results; bulk density, groundwater, geotechnical and rock characteristics; potential deleterious or contaminating substances. | · This project is resource status, not exploration status |
| Further work | · The nature and scale of planned further work (eg tests for lateral extensions or depth extensions or large-scale step-out drilling). · Diagrams clearly highlighting the areas of possible extensions, including the main geological interpretations and future drilling areas, provided this information is not commercially sensitive. | · This project is resource status, not exploration status |
| Section 3 Estimation and Reporting of Mineral Resources (Criteria listed in section 1, and where relevant in section 2, also apply to this section) | ||
| Criteria | JORC Code explanation | Commentary |
| Database integrity | · Measures taken to ensure that data has not been corrupted by, for example, transcription or keying errors, between its initial collection and its use for Mineral Resource estimation purposes. · Data validation procedures used. | · All historic data was in hardcopy format and has been initially digitised and compiled to a drillhole database in MS Access by local consultants (Beak Consultants GmbH). · Checks by both Beak and Saxore has found only minor errors and the digital data is considered to be of good quality. · Several audits by Bara and HSC checked the database for consistency. Original paper logs were inspected and compared to the database and the database was assessed to be acceptable for resource estimation. · In 2023 Saxore added further data from confirmation drilling and a significant amount of further historic data from Wismut to the MS Access drillhole database. The focus was on the intervals with low grade Sn but concentrations of other elements of potential viability, e.g. Fe2O3, Zn, Ag, Cu, WO3, In, Bi, Ge, As, Cd. · The precision and accuracy of the analytical techniques appears appropriate for mineral resource estimation. · The updated database was checked for consistency. Only minor error were found which are assessed to have no material impact on the resource estimate. · In consequence, DMT assesses that all analysis results are accurate, precise and representative to be used for a resource update. |
| Site visits | · Comment on any site visits undertaken by the Competent Person and the outcome of those visits. · If no site visits have been undertaken indicate why this is the case. | · A site visit was conducted by Ernst Bernhard Teigler (CP Resources Review) from 4th to 5th April 2022 to inspect the drilling operations at Dreiberg. · A site visit to the visitor's mine was conducted by Ernst Bernhard Teigler (CP Resources Review) with Florian Lowicki (CP Resources) and Andreas Hees (CP Metallurgy) from 4th to 5th September 2022. · The study team were accompanied by Thomas Kleinsorge (Project Director Saxore Bergbau GmbH) and Eric Hohlfeld (Project Geologist Saxore Bergbau GmbH) · An underground site visit was conducted to inspect the geology of the Hammerlein deposit and discussions relating to the geology were undertaken. |
| Geological interpretation | · Confidence in (or conversely, the uncertainty of ) the geological interpretation of the mineral deposit. · Nature of the data used and of any assumptions made. · The effect, if any, of alternative interpretations on Mineral Resource estimation. · The use of geology in guiding and controlling Mineral Resource estimation. · The factors affecting continuity both of grade and geology. | · Earlier interpretations of HSC and BARA described the Tellerhäuser tin mineralization as dominantly hosted in laterally continuous Skarn units. · DMT reviewed the existing models of Skarn units and found, that many intervals of rocks other than Skarn were included in the modelled domain to achieve continuous Skarn units. · DMT found that the skarn structure is hosted largely stratabound but with many short-range attenuations and/or split-offs. The same appearance can be observed for the mineralization hosted in the schist units underlying the skarn. · Following this interpretation concept, a domain model was prepared in Leapfrog Geo Software (Version 2023.1) using an implicit modeling methodology including Leapfrog's 'Vein Interpolator' and 'Pinch-out Tool'. · Two mineralization types Skarn and Mineralised Schist were defined following geological logs and Sn grades. For Skarn, all intervals logged as skarn were considered for modelling. For Mineralised Schist, only intervals logged as Schist with above 0.05 % Sn were considered. · A first global filter was applied to the Skarn samples filtering all lithological intervals ≥ 2 m. A first solid was generated from the 'Vein Interpolator' considering only these samples (≥2 m) to get an idea about lateral continuity, thickness, and orientation of the main skarn body. Following the trend of this main skarn body all intervals even shorter than 2 m were selected manually using the 'Interval Selection' tool. The interval selection tool works like a paintbrush to select samples. After selection these skarn intervals were set into new domains, which then were modelled to layered to lens-shaped domain bodies using the 'Vein Interpolator' and 'Pinch-out Tool'. · In the case two or more sequenced intervals were selected, the 'Vein Interpolator' used topmost and lowermost footwall- and hanging wall contact and all non-Skarn intervals in-between were included to the domain. However, the benchmark was set to a maximum of 25 % on non-domain rocks in the domain. · Skarn was subdivided into 3 domains: Main Skarn (domain 1), Skarn Lenses above Main Skarn (domain 2), and Skarn Lenses below Main Skarn (domain 3). Mineralised Schist was assigned to domain 4. A fifth domain of Schist (domain 5) was set as background lithology. This domain pattern was initially established for Hämmerlein area. The Main Skarn and Mineralized Schist was modelled continuously, while the Skarn lenses were modelled using the Pinch-out Tool. For the resource update of the Tellerhäuser project area, it was decided to apply the Pinch-out Tool to all domains in order to avoid non-Skarn rocks in Skarn domain and non-mineralised schist in Mineralised Schist domain. · The fault model supplied by Saxore (done by HSC in 2019) was applied to the model. · In order to honour the very short-range variations in thickness and to enable Leapfrog to model the domain bodies accordingly, the surface resolution was set to very low values of around 1 or 2 m. · Some database inconsistencies of overlapping data caused by incorrectly entered drilling orientation of fan drilling made implicit modelling fail for these overlapping hole information, which was solved by using support points to guide the implicit model. · For all modelled volume bodies, a volume reduction was carried out considering existing exploration workings including a shield of 6 m radius around the centerline of these workings. A clipping operation was performed in Leapfrog. The Clip Volume is used to outersect the volume body of 6 m-shield from the domain solids. · Overall, 27 volume bodies were modelled, 5 in Hämmerlein (3 layers of Skarn, 2 layers of Mineralised Schist), 14 in Dreiberg (all Skarn), 8 in Zweibach (7 layers of Skarn, 1 layer of Mineralised Schist) · A block model was generated with the dimensions 10mx10mx1m. The limits used were the same limits defined in the domain model. A volume percentage attribute was calculated for each of the 27 volume bodies reduced by existing workings including the surrounding shield. Volume percentage was calculated in order to ensure 100 % match between volume bodies and block model volume. · Then, the 27 volume percentage attributes were unified (summed) to 5 attributes representing each of the five domains: main Skarn layer (domain 1), Skarn lenses above main Skarn (domain 2), Skarn lenses below main Skarn (domain 3), Mineralized Schist (domain 4) and schist as back ground (domain 5). Two integer attributes listing the number of layer bed running from 1 to 27 and the domain number running from 1 to 5. |
| Dimensions | · The extent and variability of the Mineral Resource expressed as length (along strike or otherwise), plan width, and depth below surface to the upper and lower limits of the Mineral Resource. | · The Hämmerlein skarn is relatively flat lying with horizontal to 10 degrees dip to the SE. Skarn is interpreted to measure 2 km down dip and 1.5 km across strike. It averages in thickness to around 2 m with maximum of 4 m (StdDev or 66 Percentile). Mineralised Schist follows the Skarn above and below with average thickness of around 6 m with maximum of 15 m (StdDev or 66 Percentile). Mineralization is 200-300 m below the surface. · The Dreiberg skarn continuous to SE and is also relatively flat lying with horizontal to 10 degrees dip to the SE. Skarn is interpreted to measure 3.3 km down dip and 1.3 km across strike. It averages in thickness to around 3 m with maximum of 6 m (StdDev or 66 Percentile). Mineralization is 300-1000 m below the surface. · The Zweibach skarn is relatively flat lying with horizontal to 10 degrees dip to the SE parallel to Dreiberg but separated with 300 m offset by a SE running normal fault. Skarn is interpreted to measure 2.3 km down dip and 0.6 km across strike. It averages in thickness to around 2 m with maximum of 4 m (StdDev or 66 Percentile). Mineralised Schist follows the Skarn below with average thickness of around 23 m with maximum of 46 m (StdDev or 66 Percentile). Mineralization is 200-300 m below the surface. |
| Estimation and modelling techniques | · The nature and appropriateness of the estimation technique(s) applied and key assumptions, including treatment of extreme grade values, domaining, interpolation parameters and maximum distance of extrapolation from data points. If a computer assisted estimation method was chosen include a description of computer software and parameters used. · The availability of check estimates, previous estimates and/or mine production records and whether the Mineral Resource estimate takes appropriate account of such data. · The assumptions made regarding recovery of by-products. · Estimation of deleterious elements or other non-grade variables of economic significance (eg sulphur for acid mine drainage characterisation). · In the case of block model interpolation, the block size in relation to the average sample spacing and the search employed. · Any assumptions behind modelling of selective mining units. · Any assumptions about correlation between variables. · Description of how the geological interpretation was used to control the resource estimates. · Discussion of basis for using or not using grade cutting or capping. · The process of validation, the checking process used, the comparison of model data to drill hole data, and use of reconciliation data if available. | · Resource block model was established with block size of X = 10 m, Y = 10 m, Z = 1 m. No sub-blocking was applied · Compositing was done based on 1 m as it is the 90 percentile for both the drill holes and the channels. · Compositing was done for each layer separately. · Outliers were top-cut at 99.9 Percentile in order to exclude around one sample per mille. For resource model diluted and top-cut composites were used, once to treat un-sampled intervals as blank material and once not to bias interpolation by high grade outliers, both in order not to overestimate the resource. · For Sn a sufficient amount and density of data was available in Hämmerlein to produce variograms in acceptable quality for the domain of Skarn and Mineralised Schist. Thus, the resulting parameters were used to interpolate Sn in domains of Skarn and Mineralized Schist by OK for all the areas of Tellerhäuser project area. The other elements Fe2O3, Zn, Ag, Cu, WO3, In, Bi, Ge, As, Cd were interpolated using IDW. · Exponential omnidirectional variogram model for data of Sn in Skarn show a range of 140 m, a nugget of 0.16 and a sill of 0.18 (orientation -10 degrees to SE) · Exponential omnidirectional variogram model for data of Sn in Mineralised Schist show a range of 140 m, a nugget of 0.022 and a sill of 0.022 (orientation -10 degrees to SE) · In order to reduce smoothing effects, the interpolation was done in several passes with increasing sizes of the search ellipsoid, minimum number of composite samples coming from a minimum number of holes · Model validation shows good reproduction of primary data · The resource block model was validated to demonstrate that the applied methodology to model geology and grade has produced a model which is representative to primary data of holes and channels. · This validation focused on the two key factors tonnage and grade of Skarn+Mineralised Schist. Applying Sn cut-off grades to database limited to intersections of Skarn+Mineralised Schist, a percentage of remaining intervals was calculated and compared to percentage of remaining tonnage from indicated resource of Skarn+Mineralised Schist. · The comparison demonstrates that the assayed Sn concentrations from drilling and channels are representatively reflected in the block model. Slight discrepancy is to be expected because of the drill pattern, which does not provide 100 % regular intersections of the mineralisation. The other reason is the typical smoothing caused by the compositing using dilution for un-sampled intervals and interpolation process itself. · Volume domains of mineralisation type of Skarn show good alignment with skarn intersections with only a few exceptions caused by sporadic database errors which are assessed to have no material effect on the resource estimate. However, these should be corrected in future, when historic documentation enables. · Volume domains of mineralisation type of Mineralised Schist include intervals of non-Mineralised Schist in order to produce continuous bodies including the most higher-grade intervals of Sn. The non-mineralised intervals were corrected in the resource model by using diluted composites. · Resource History: In comparison to the indicated resources of HSC 2019, contained tonnage of Sn metal in Skarn+Mineralised Schist could be increased by almost 37% from 33 000 t to 45 000 t considering a Sn cut-off grade of 0.2 % for both Skarn and Mineralised Schist. The main factors for the increase are a higher bulk density derived from additional data and a slightly higher geostatistical range for indicated resources. However, there is a significant increase in sample availability since 2019 and 2023 resource estimate. From 42 726 additional Sn values only 1164 samples were above 0.2 % Sn. The vast majority is below 0.2 % Sn. |
| Moisture | · Whether the tonnages are estimated on a dry basis or with natural moisture, and the method of determination of the moisture content. | · All tonnage and grade is on a dry basis. |
| Cut-off parameters | · The basis of the adopted cut-off grade(s) or quality parameters applied. | · Following the development of the Sn price at LME for the last 15 years, the recent price situation and increased demand assumed for future electromobility and renewable energy, the future price is assessed up to 25,000 USD per metric tonne of Sn, refined, 99.85 % purity. · This would correspond to an ROM ore grade of approx. 0.5 % Sn which is assumed to be realized at 0.2 % Sn cut-off grade. Thus, for Skarn and Mineralised Schist a 0.2 % Sn cut-off grade is applied. |
| Mining factors or assumptions | · Assumptions made regarding possible mining methods, minimum mining dimensions and internal (or, if applicable, external) mining dilution. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider potential mining methods, but the assumptions made regarding mining methods and parameters when estimating Mineral Resources may not always be rigorous. Where this is the case, this should be reported with an explanation of the basis of the mining assumptions made. | · The Mineral Resources were estimated on the assumption that the material will be mined by an appropriate underground method e.g. room and pillar, stopes. |
| Metallurgical factors or assumptions | · The basis for assumptions or predictions regarding metallurgical amenability. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider potential metallurgical methods, but the assumptions regarding metallurgical treatment processes and parameters made when reporting Mineral Resources may not always be rigorous. Where this is the case, this should be reported with an explanation of the basis of the metallurgical assumptions made. | · The available metallurgical testwork indicates that tin is recoverable by gravity separation and flotation. · Magnetic separation is required to remove iron as part of the process circuit and iron may be recovered as a by-product. The Company estimates approximately 5% of Iron is present in phases other than Magnetite and Hematite. · It is also expected that zinc will need to be removed by floatation to improve gravity recovery and zinc may be recovered as a by-product. · Indium is expected to report to a copper sulphide concentrate that will be recoverable via flotation. (The Company report that the indium occurs as roquesite, a copper-indium-sulphide). |
| Environmental factors or assumptions | · Assumptions made regarding possible waste and process residue disposal options. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider the potential environmental impacts of the mining and processing operation. While at this stage the determination of potential environmental impacts, particularly for a greenfields project, may not always be well advanced, the status of early consideration of these potential environmental impacts should be reported. Where these aspects have not been considered this should be reported with an explanation of the environmental assumptions made. | · Environmental factors have not been investigated for the purposes of the Resource Estimate reported here. · It is expected that processing will be completed underground and the existing underground development will offer some space for disposal of waste materials. |
| Bulk density | · Whether assumed or determined. If assumed, the basis for the assumptions. If determined, the method used, whether wet or dry, the frequency of the measurements, the nature, size and representativeness of the samples. · The bulk density for bulk material must have been measured by methods that adequately account for void spaces (vugs, porosity, etc), moisture and differences between rock and alteration zones within the deposit. · Discuss assumptions for bulk density estimates used in the evaluation process of the different materials. | · Density is based on measured samples. All samples total to an average bulk density of 3.86 t/m³ for Skarn and 2.88 t/m³ for Mineralised Schist. For the resource model, DMT attributed a bulk density of 2.9 t/m³ to Mineralised Schist and reduced the bulk density of Skarn to 3.6 t/m³ because the Skarn domain may contain up to 25 % schist. · Several cross-checks were done by DMT to confirm the bulk density of the Skarn domain, which comprises different types of skarn with variable proportions of skarn-associated silicates, magnetite, sulphides and quartz. Firstly, DMT reviewed all measurements by checking plausibility of each measurement and attributing ranges of bulk densities plausible for skarn types sensu stricto. The resulting density of skarn is 3.6 t/m³. Secondly, DMT calculated a skarn bulk density of 3.6 t/m³ based on the mineral composition of the bulk sample sent to ALS Burnie and mineral densities from the literature |
| Classification | · The basis for the classification of the Mineral Resources into varying confidence categories. · Whether appropriate account has been taken of all relevant factors (ie relative confidence in tonnage/grade estimations, reliability of input data, confidence in continuity of geology and metal values, quality, quantity and distribution of the data). · Whether the result appropriately reflects the Competent Person's view of the deposit. | · Resource classification within mineralization envelopes for Skarn and Mineralised Schist is generally based on spacing of drill holes and channels, grade continuity, and overall geological continuity. The distance to the nearest composite and the number of drill holes or channels are also considered in the classification. In classifying the resource estimate, the following key factors have been considered: · Confidence in data quality and quantity and specifically sample spacing of Sn data; · Confidence in the geological interpretation and continuity (geological complexity); and · Confidence in mineralization / grade continuity (complexity of spatial grade distribution). · Considering the above, the following criteria have been applied for classification into the various mineral resource categories for this estimate. Half the geostatistical range of 140 m was considered in this classification. · Indicated Resources: · All blocks within the wireframed constraints and 70 m maximum distance to nearest Sn sample and a minimum of 3 composites from a minimum of 2 drill holes or channels. · Inferred Resources: · All blocks within the wireframed constraints and 70 m minimum distance to nearest Sn sample and a minimum of 2 composites from a minimum of 1 drill hole. |
| Audits or reviews | · The results of any audits or reviews of Mineral Resource estimates. | · No audits of the Mineral Resource estimates have been completed. · The estimates of resources have been compared to previous estimates and are comparable. |
| Discussion of relative accuracy/ confidence | · Where appropriate a statement of the relative accuracy and confidence level in the Mineral Resource estimate using an approach or procedure deemed appropriate by the Competent Person. For example, the application of statistical or geostatistical procedures to quantify the relative accuracy of the resource within stated confidence limits, or, if such an approach is not deemed appropriate, a qualitative discussion of the factors that could affect the relative accuracy and confidence of the estimate. · The statement should specify whether it relates to global or local estimates, and, if local, state the relevant tonnages, which should be relevant to technical and economic evaluation. Documentation should include assumptions made and the procedures used. · These statements of relative accuracy and confidence of the estimate should be compared with production data, where available. | · All Resources are classified as Indicated and Inferred. Due to the reliance on legacy data and the inherently erratic nature of Sn grades not measured resource classifications have been applied. · The Mineral Resource Estimates are considered to have sufficient global and local accuracy to allow mine planning in the Indicated resources where tin only is used to determine cut-off grade. · Inferred resources do not have sufficient local accuracy and carry a higher global estimation risk than indicated resources. · The Mineral Resource Estimates of the Tellerhäuser deposits are sensitive to the cut-off grade applied. Increasing the confidence in by product metal estimation may allow for further de risking in select area where further sampling is possible. · Areas of inferred resources require infill drilling to improve confidence in mineral resource estimated. |
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