Announcement PDF ASX Announcement 13 May 2024 ASX: OD6 High Metallurgical Recoveries Continue at Splinter Rock Project OD6 Metals Limited (OD6 or the Company) is pleased to announce that high metallurgical recoveries continue to be achieved at Splinter Rock, from Phase 3 samples tested at the Australian Nuclear Science Organisation (ANSTO). Highlights: • Achieved high metallurgical recoveries, up to 90%, of Magnet Rare Earth Elements (MagREE) in multiple Prospect areas, across 71 new samples • • Average ~60% MagREE recovery at 25g/l HCl (excluding basin edges and carbonaceous shales) – Centre Prospect: 42% to 90% recovery of MagREE – Inside Centre Prospect: 44% to 76% recovery of MagREE – Prop Prospect: 41% to 77% recovery of MagREE Importantly recoveries for all magnet rare earth oxides (MagREO) inclusive of Nd, Pr, Dy, Tb are similar. This is the key to overall project economics for any clay hosted rare earth project. • The data is being considered as part of the future Mineral Resource Estimate Upgrade expected to be available this quarter. • Further Phase 4 metallurgical leaching and processing optimisation work underway at ANSTO • All assays contained in this ASX announcement are based on the 4-Acid soluble digestion method, aligning with the reporting of geological drill assays and the Mineral Resource Estimate. Brett Hazelden, Managing Director, commented: “The results continue to show that the Splinter Rock Recoveries are as good as or better than the Brazilian Clay hosted Rare Earth plays that have gained so much attention over the last 12 months, and continues to affirm that we are Australia’s premier clay-hosted rare earth deposit. The Inside Centre recoveries of ~60% when combined with grades of between 1,400 to 2,200ppm TREO, across an extensive 2km by 1km areas, with substantial thicknesses between 20 to 77m, a low stripping ratio, plus low acid consumptions continues to be a standout for the company. These metrics align closely with the essential value drivers we believe are crucial for the economic viability of clayhosted rare earth projects both in Australia and globally. At the Splinter Rock Project we have no private royalties, do not sit over farming land, are located in a known wind and solar renewable energy corridor, plus we are only a short distance to the major port of Esperance. We look forward to these factors being considered as part of our future Mineral Resource Estimate upgrade scheduled for later this quarter” MagREE (Magnet Rare Earths) = Nd + Pr + Tb + Dy) MagREO (Magnet Rare Earth Oxide) = Nd2O3 + Pr6O11 + Tb4O7 + Dy2O3 TREO (Total Rare Earth Oxide) = La2O3 + CeO2 + Pr6O11 + Nd2O3 + Sm2O3 + Eu2O3 + Gd2O3 + Tb4O7 + Dy2O3 + Ho2O3 + Er2O3 + Tm2O3 + Yb2O3 + Lu2O3 + Y2O3. Metallurgical Sample Selection A total of 71 samples were selected from a wide variety of clays, locations and depths to further develop a geometallurgical understanding of recovery across the various regolith types at our two large prospects at Splinter Rock (Centre and Prop). Samples were chosen based on differing geographic locations, REE grades, colours, chemical compositions, AEM conductivity, proximity to granite, basin position (including paleo valley/channel positions) and inferred geological genesis. Refer to figures 1, 2 and 3 for Phase 3 sample locations along with those previously completed during Phases 1 and 2. Figure 1: Splinter Rock Scrum and Centre metallurgical sample drill hole locations on AEM model clay thickness 2 Figure 2: Splinter Rock Inside Centre metallurgical sample drill hole locations on AEM model clay thickness Figure 3: Splinter Rock Prop and Flanker metallurgical sample drill hole locations on AEM Model clay thickness 3 Centre Prospect Results Centre Prospect results are presented in Table 1 and Figure 4. These results are based on three geological locations, each with its own clay setting and granite basin boundaries. The main Centre Prospect is a large clay basin located within an elevated tableland, featuring multiple feeder channels and Booanya granite to the north. Based on the recovery results, the following observations can be made: Inside Centre • Is a significant feeder channel heading northeast into the main Centre Basin • MagRE Recoveries (extractions) across all four MagRE elements average between 44% and 76%. • Areas on the margin of the clay basin have lower recovery, likely due to the transition between clay and saprock due to weathering. • No carbonaceous shales are found in this channel Centre North • Is a large Clay basin to the north and western edge of the main prospect • MagRE Recoveries (extractions) across all four MagRE elements average between 42% to 90%. • A carbonaceous shale (black clay) located in parts of the basin is likely the remnants of a historic estuary. Recoveries and grades of rare earth located in this carbonaceous material are generally lower and have a corresponding increase in sulphur levels. • Below the carbonaceous shales recoveries and grades generally increase significantly. Centre • Is a large Clay Basin covering a vast area in the southern western area of the main prospect • MagRE Recoveries (extractions) across all four MagRE elements average between 48% to 68%. • Areas on the margin of clay basin have lower recovery, likely due to the transition between clay and saprock due to weathering. • A carbonaceous shale (black clay) located in parts of the basin is likely the remnants of a historic estuary. Recoveries and grades of rare earth located in this carbonaceous material are generally lower and have a corresponding increase in sulphur levels. • Below the carbonaceous shales recoveries and grades generally increase significantly. Table 1: Centre Prospect MagRE acid leach recovery for various drill hole locations, intercepts and sample types Composite ID Inside Centre SRAC0356 51-72m SRAC0356 72-79m SRAC0357 39-54m SRAC0357 54-90m SRAC0358 36-54m SRAC0358 54-84m SRAC0359 27-51m SRAC0359 51-87m SRAC0470 33-57m Head Assay TREO MagREO ppm ppm 1842 454 952 193 2108 479 1787 409 1473 282 1984 595 1495 291 1470 338 2335 539 Nd % 44% 75% 44% 65% 76% 56% 51% 62% 35% % MagRE Recovery Pr Tb Dy MagRE % % % % 42% 48% 44% 44% 73% 75% 74% 74% 41% 40% 38% 43% 63% 66% 64% 64% 75% 71% 67% 76% 55% 57% 56% 56% 51% 48% 46% 51% 60% 60% 58% 61% 38% 43% 39% 36% Sample Selection location, rock type, colour (brown, red, grey clay) (grey clay) (cream, grey clay) (brown, green clay) (brown clay) 4 Composite ID SRAC0301 21-33m % MagRE Recovery Nd Pr Tb Dy MagRE % % % % % 44% 43% 49% 50% 44% 90% 90% 84% 80% 90% 46% 46% 49% 48% 46% 69% 69% 66% 62% 69% 1% 1% 20% 28% 3% 52% 48% 49% 51% 51% 71% 70% 79% 79% 72% 75% 73% 76% 73% 74% 79% 78% 74% 70% 78% 46% 38% 47% 47% 44% 56% 50% 66% 66% 56% 9% 8% 15% 16% 10% 43% 38% 50% 51% 42% 61% 58% 64% 64% 60% 57% 56% 58% 56% 57% 51% 53% 54% 51% 52% 49% 50% 56% 53% 49% 48% 47% 58% 55% 48% 82% 81% 78% 74% 81% 8% 8% 10% 8% 8% 48% 48% 54% 54% 48% 10% 9% 16% 16% 10% 12% 9% 22% 20% 12% 3% 3% 5% 5% 3% 49% 46% 50% 45% 48% 60% 58% 60% 56% 59% 34% 32% 43% 42% 34% SRAC0302 27-41m 1031 251 66% 68% 63% 61% 66% (black clay) SRAC0303 21-39m 1024 221 53% 52% 52% 48% 53% (dark grey clay) SRAC0307 18-27m 2605 624 27% 25% 24% 25% 27% (brown clay) SRAC0308 12-24m 1629 342 12% 10% 14% 14% 12% (cream, dark grey clay) SRAC0310 36-42m 973 231 20% 19% 20% 17% 20% SRAC0310 42-50m 1502 374 68% 65% 73% 72% 67% SRAC0311 42-60m 1138 285 58% 57% 62% 63% 59% (grey clay) SRAC0314 27-39m 1615 242 39% 39% 42% 40% 39% (grey clay) SRAC0325 33-43m SRAC0326 18-27m SRAC0327 30-45m SRAC0328 24-42m SRAC0328 42-52m SRAC0330 30-45m SRAC0333 30-42m Centre North SRAC0333 42-73m SRAC0335 39-60m SRAC0337 39-51m SRAC0337 51-63m SRAC0338 30-42m SRAC0339 51-63m SRAC0340 48-60m SRAC0340 60-72m SRAC0469 39-48m SRAC0469 48-70m SRAC0291 21-33m SRAC0291 33-49m SRAC0297 18-27m SRAC0297 27-36m SRAC0298 12-27m SRAC0298 27-47m SRAC0300 12-21m SRAC0300 21-39m Centre Sample Selection location, rock type, colour Head Assay TREO MagREO ppm ppm 2457 682 2811 618 1207 270 1564 348 1160 252 1696 338 3218 1013 1064 286 1061 226 870 181 1287 327 1338 351 1616 411 1571 344 2033 377 1265 342 1638 367 1384 305 809 184 1834 456 1833 432 1497 352 1885 487 2421 589 845 136 1504 381 940 175 SRAC0300 39-55m (black clay) (brown clay) (white clay) (grey clay) (grey clay) (grey clay) (grey clay) (grey clay) (grey clay) (brown, grey clay) (grey, brown clay) (brown, black clay) (brown, grey, black clay) (grey clay) (brown clay) (grey, brown clay) (brown, grey clay) (grey clay) Note: There will be some variation between original head grade total assay and the sum of residual solid and liquor assays which is not accounted for. Recoveries only reflect initial rare earth leaching, with further losses expected in precipitation, impurity removal, purification and drying. 5 Figure 4: Centre Prospect REE Recovery by Element (>40% MagREO recovery) Prop Prospect Results Prop Prospect results are presented in Table 2 and Figure 5. The Prop Prospect is located at the lowest elevation at Splinter Rock and is surrounded by Booanya granite to the north and south, is interpreted to be a paleo-valley filled with clay, featuring multiple feeder channels. Based on the recovery results it can be observed that: • MagRE Recoveries (extractions) across all four MagRE elements are more variable, averaging between 41% and 77%. • Areas on the margin of clay basin and also to the west have lower recovery, most likely due to the transition between clay and saprock caused by weathering. • The highest recoveries are located in the centre of the Prop deposit along a central NW to SE channel • Other rare earth elements are recovered in similar quantities with most elements exhibiting a broader range of recoveries • Some black carbonaceous shales (black clay) have been located in parts of the basin and are likely remnants of a historic estuarine river. Recoveries and grades of rare earth located in this carbonaceous material are generally lower and have a corresponding increase in sulphur levels. Table 2: Prop Prospect MagRE acid leach recovery for various drill hole locations, intercepts and sample types Composite ID Prop Nd % 19% % MagRE Recovery Pr Tb Dy MagRE % % % % 14% 23% 21% 18% Sample Selection location, rock type, colour 229 49% 48% 43% 44% 49% (brown, green clay) 356 54% 51% 56% 58% 53% (grey, brown, purple clay) SRAC0361 30-42m Head Assay TREO MagREO ppm ppm 817 195 SRAC0371 48-56m 923 SRAC0377 39-61m 1644 (Red, brown clay) 6 Composite ID Head Assay TREO MagREO ppm ppm Nd % % MagRE Recovery Pr Tb Dy MagRE % % % % SRAC0385 24-39m 1027 216 0% -1% 4% 3% 0% SRAC0397 24-33m 911 990 935 1229 677 715 779 543 3315 843 1026 1510 1114 1502 1217 1166 988 905 1590 1252 865 199 168 200 262 146 160 174 165 828 207 207 358 264 361 272 277 241 242 401 300 215 66% 56% 11% 50% 48% 67% 69% 47% 69% 41% 29% -7% -3% 49% -4% 14% 43% 33% 37% 43% 78% 61% 50% 14% 49% 41% 64% 63% 40% 68% 37% 25% -9% -9% 53% -1% 17% 40% 29% 38% 45% 76% 70% 32% 21% 44% 59% 68% 66% 51% 74% 32% 35% -5% -9% 29% 1% 14% 30% 43% 39% 44% 68% 69% 27% 20% 42% 60% 67% 65% 52% 72% 31% 32% -3% -7% 24% 2% 11% 29% 46% 42% 42% 66% 65% 53% 12% 49% 47% 66% 68% 46% 69% 39% 28% -7% -4% 49% -3% 14% 41% 33% 37% 43% 77% SRAC0397 54-68m SRAC0398 21-33m SRAC0398 33-45m SRAC0398 45-54m SRAC0399 18-27m SRAC0399 27-37m SRAC0401 66-78m SRAC0402 18-21m SRAC0403 42-57m SRAC0403 57-68m SRAC0404 12-24m SRAC0406 24-33m SRAC0406 33-56m SRAC0408 15-39m SRAC0410 30-54m SRAC0410 54-66m SRAC0411 36-57m SRAC0425 45-82m SRAC0432 27-41m SRAC0433 12-27m Sample Selection location, rock type, colour (red clay) (grey, red clay) (grey clay) (grey clay) (brown clay) (red clay) (brown clay) (brown clay) (grey clay) (grey clay) (grey, brown clay) (grey, brown clay) (black, grey clay) (brown clay) (brown clay) Figure 5: Prop Prospect REE Recovery by Element (>40% MagREO recovery) 7 Leach Conditions OD6 and ANSTO have developed a project specific bottle roll test procedure utilising a 25 g/L hydrochloric acid solution, nominally maintained at 30C and ambient pressure, with a 4 wt% solids density over a 24-hour period. Recoveries are then calculated based on the difference between the assayed solid head and solid residue using a 4-acid digestion method. This procedure was developed and benchmarked against previous tests to achieve results equivalent to diagnostic leach tests using a 25 g/L hydrochloric acid, at notionally ambient conditions and pressures, over a 6hour period. The leach conditions were selected based on previously announced works for consistency (refer ASX announcements, 27 February 2024, 7 November 2023 and 3 April 2023). Further optimisation works will be undertaken in future test work programs. The bottle roll method is devised to be an inexpensive and fast technique for determining the leachability of samples. ANSTO utilises a 4 wt% solids density for all clay hosted rare earth projects inclusive of acid soluble and ionic diagnostic tests. Once further bench scale testing is undertaken, it is anticipated that a slurry density of between 25 and 30% is likely to be optimal, as has been recorded on a number of other projects, with little to no decrease in leach recoveries. Test work results should be interpreted in the context of geological setting, selection of known non-clay samples to identify boundary limits, and OD6’s objectives to test various clay types to identify areas of favourable geology and metallurgy whilst delineating the extent of these areas. Assay Method The Splinter Rock clay hosted prospect areas are characterised by a combination of ionically adsorbed, acidsoluble and refractory rare earth elements (REEs). Our chosen assay method (4-acid digestion) does not report the refractory rare earth component, aiming to eliminate the variable grade proportion of the refractory material, which could introduce modelling errors in the future. Work conducted by OD6 continues to demonstrate that utilising the alternative Lithium Borate Fusion Digest method can increase the head grade by up to 30% compared to the 4-acid assay method. However, it is important to note that this extra grade is highly unlikely to be recoverable in any proposed clay hosted rare earth process flowsheet. All assays contained in this ASX announcement are based on the 4-acid soluble digestion method, rather than the ALS Lithium Borate Fusion Digest method, aligning with OD6’s reporting of geological drill assays and the Mineral Resource Estimate. It should be acknowledged that future potential commercial production of REE is significantly improved through successful leaching of both ionic and acid-soluble REEs. 8 Forward Works Program • Incorporation of Results into Mineral Resource Estimate: Evaluate and potentially upgrade the Mineral Resource Estimate based on the latest results. • Bench Scale Tests: Perform bench scale tests to determine preferred slurry densities and further optimize leach conditions. • Slurry Leach Tests: Conduct slurry leach tests to evaluate slurry handling, filtration, and washing processes. • Impurity Removal Trials: Conduct impurity removal trials under various pH conditions, temperatures, and with different reagents. • Assessment of Resin Use: Evaluate the potential use of resins in both pulp and liquid phases to assist in impurity removal. • Ion Exchange Assessment: Assess ion exchange processes on "leach" liquor and investigate selective elution of REE versus impurities such as Al and Fe. • Nanofiltration Evaluation: Evaluate nanofiltration processes to produce a retentate with increased REE concentration and a permeate containing clean acid for recycling. • Mixed Rare Earth Precipitation: Investigate mixed rare earth precipitation methods, including carbonates and hydroxides. • Process Modelling and Techno-Economic Comparison: Develop process models and conduct technoeconomic comparisons of various flowsheet options. • Mini Pilot Scale Testing: Conduct mini pilot scale testing using composited bulk samples to validate findings on a smaller scale. • Conversion of Rare Earth Carbonate/Hydroxide: Apply process models to assess options for converting mixed rare earth carbonate/hydroxide in a downstream refinery to multiple potential rare earth oxides. 9 Competent Persons Statement Information in this report relating to Exploration Results is based on information reviewed by Mr Jeremy Peters who is a Fellow of the Australasian Institute of Mining and Metallurgy and a Chartered Professional Geologist and Mining Engineer of that organisation. Mr Peters is a Director of Burnt Shirt Pty Ltd, consulting to OD6 and has sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activity which he is undertaking to qualify as a Competent Person as defined by the 2012 Edition of the Australasian Code for reporting of Exploration Results, Mineral Resources and Ore Reserves. Mr Peters consents to the inclusion of the data in the form and context in which it appears. The information in this report relating to the Mineral Resource estimate for the Splinter Rock Project is extracted from the Company’s ASX announcement dated 18 July 2023. OD6 confirms that it is not aware of any new information or data that materially affects the information included in the original announcement and that all material assumptions and technical parameters underpinning the Mineral Resource estimate continue to apply. Forward Looking Statements Certain information in this document refers to the intentions of OD6 Metals, however these are not intended to be forecasts, forward looking statements, or statements about the future matters for the purposes of the Corporations Act or any other applicable law. Statements regarding plans with respect to OD6 Metals projects are forward looking statements and can generally be identified by the use of words such as ‘project’, ‘foresee’, ‘plan’, ‘expect’, ‘aim’, ‘intend’, ‘anticipate’, ‘believe’, ‘estimate’, ‘may’, ‘should’, ‘will’ or similar expressions. There can be no assurance that the OD6 Metals plans for its projects will proceed as expected and there can be no assurance of future events which are subject to risk, uncertainties and other actions that may cause OD6 Metals actual results, performance, or achievements to differ from those referred to in this document. While the information contained in this document has been prepared in good faith, there can be given no assurance or guarantee that the occurrence of these events referred to in the document will occur as contemplated. Accordingly, to the maximum extent permitted by law, OD6 Metals and any of its affiliates and their directors, officers, employees, agents and advisors disclaim any liability whether direct or indirect, express or limited, contractual, tortuous, statutory or otherwise, in respect of, the accuracy, reliability or completeness of the information in this document, or likelihood of fulfilment of any forward-looking statement or any event or results expressed or implied in any forward-looking statement; and do not make any representation or warranty, express or implied, as to the accuracy, reliability or completeness of the information in this document, or likelihood of fulfilment of any forward-looking statement or any event or results expressed or implied in any forward-looking statement; and disclaim all responsibility and liability for these forward-looking statements (including, without limitation, liability for negligence). This announcement has been authorised for release by the Board of OD6 Metals Limited 10 About OD6 Metals OD6 Metals is an Australian public company pursuing exploration and development opportunities within the critical mineral sector. The Company has successfully identified clay hosted rare earths at its 100% owned Splinter Rock and Grass Patch Projects, which are located in the Esperance-Goldfields region of Western Australia - about 30 to 150km northeast of the major port and town of Esperance. Drilling and geological analysis at its flagship Splinter Rock has shown widespread, thick, high-grade clay hosted REE deposits that extend over hundreds of square kilometres. Metallurgical testing using hydrochloric acid to leach the rare earths have resulted in positive REE recoveries with optimisation ongoing. The Company aims to delineate and define economic resources and reserves of Rare Earth Elements (REE), in particular Neodymium (Nd), Praseodymium (Pr), Dysprosium (Dy) and Terbium (Tb), which can be developed into a future revenue generating mine. Clay REE deposits are currently economically extracted in China, which is the dominant world producer of REEs. REE are becoming increasingly important in the global economy, with uses including advanced electronics and permanent magnets in electric motors. As an example, a neodymium magnet used in a wind turbine or electric vehicle motor is 18 times stronger than a standard ferrite magnet significantly increasing energy use efficiency. As part of the exploration process the Company has entered into heritage agreements with Esperance Tjaltrjraak Native Title Aboriginal Corporation and the Ngadju Native Title Aboriginal Corporation that serves to both enable exploration and protect important cultural sites on Country. Corporate Directory Managing Director Mr Brett Hazelden Non-Executive Chairman Dr Darren Holden Non-Executive Director Mr Piers Lewis Non-Executive Director Dr Mitch Loan Financial Controller/ Joint Company Secretary Mr Troy Cavanagh Joint Company Secretary Mr Joel Ives Exploration Manager Tim Jones Contact OD6 Metals Ltd ACN 654 839 602 www.od6metals.com.au Mail to: info@od6metals.com.au Phone: +61 8 6189 8515 Level 1, 50 Kings Park Road, West Perth, WA 6005 PO Box 277, North Beach, WA 6920 PO Box 2009, Esperance, WA 6450 11 Metallurgical Drill Hole Location Details Hole ID Type Easting Northing RL (m) Dip (degrees) End of Hole (m) SRAC0291 Aircore 499186 6338152 206 -90 49 SRAC0297 Aircore 497503 6336490 204 -90 36 SRAC0298 Aircore 497181 6336252 202 -90 47 SRAC0300 Aircore 496404 6336432 208 -90 55 SRAC0301 Aircore 496028 6336565 212 -90 36 SRAC0302 Aircore 497440 6334719 205 -90 41 SRAC0303 Aircore 497223 6334383 205 -90 43 SRAC0307 Aircore 498089 6335722 202 -90 27 SRAC0308 Aircore 498313 6336054 203 -90 27 SRAC0310 Aircore 498814 6336676 208 -90 50 SRAC0311 Aircore 499097 6336958 205 -90 60 SRAC0314 Aircore 499566 6338039 205 -90 41 SRAC0325 Aircore 501855 6341344 203 -90 43 SRAC0326 Aircore 501260 6341403 203 -90 55 SRAC0327 Aircore 501763 6341732 203 -90 60 SRAC0328 Aircore 501762 6342132 204 -90 52 SRAC0330 Aircore 501756 6342932 205 -90 49 SRAC0333 Aircore 502529 6343475 201 -90 73 SRAC0335 Aircore 503329 6343487 195 -90 60 SRAC0337 Aircore 504100 6343677 195 -90 63 SRAC0338 Aircore 504472 6343823 194 -90 56 SRAC0339 Aircore 504861 6343919 193 -90 63 SRAC0340 Aircore 505260 6344002 193 -90 72 SRAC0356 Aircore 501767 6337263 206 -90 79 SRAC0357 Aircore 502068 6336999 205 -90 95 SRAC0358 Aircore 502177 6336615 204 -90 84 SRAC0359 Aircore 501939 6336293 204 -90 87 SRAC0361 Aircore 515633 6324245 147 -90 49 SRAC0371 Aircore 515666 6326792 148 -90 56 SRAC0377 Aircore 518227 6328120 149 -90 61 SRAC0385 Aircore 514718 6325247 147 -90 40 SRAC0397 Aircore 517487 6329839 147 -90 68 12 Hole ID Type Easting Northing RL (m) Dip (degrees) End of Hole (m) SRAC0398 Aircore 517215 6330131 143 -90 54 SRAC0399 Aircore 516907 6330385 146 -90 37 SRAC0401 Aircore 516895 6329352 149 -90 81 SRAC0402 Aircore 516495 6329353 146 -90 21 SRAC0403 Aircore 516095 6329354 147 -90 68 SRAC0404 Aircore 515694 6329357 147 -90 69 SRAC0406 Aircore 514893 6329362 149 -90 56 SRAC0408 Aircore 514091 6329364 146 -90 40 SRAC0410 Aircore 516577 6330149 150 -90 66 SRAC0411 Aircore 516580 6330549 146 -90 60 SRAC0425 Aircore 520849 6333885 158 -90 82 SRAC0432 Aircore 517069 6335615 154 -90 41 SRAC0433 Aircore 516744 6335759 153 -90 27 SRAC0469 Aircore 501662 6341390 203 -90 70 SRAC0470 Aircore 502305 6336788 203 -90 60 13 JORC 2012 – Table1: Splinter Rock Section 1 Sampling Techniques and Data (Criteria listed in the preceding section also apply to this section) Criteria JORC Code explanation Commentary Sampling techniques • • • • • Drilling techniques Drill sample recovery • • • • Logging • • • Sub-sampling techniques and sample preparation • • • • • • 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. Drill type (eg core, reverse circulation, openhole hammer, rotary air blast, auger, Bangka, sonic, etc) and details (eg core diameter, triple or standard tube, depth of diamond tails, facesampling bit or other type, whether core is oriented and if so, by what method, etc). 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. 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. 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 subsampling 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. • • • • • • • • • • • • • • • • • Geochemical sampling was undertaken by sampling of metre interval samples returned from the cyclone of a conventional air core drilling rig. Certified reference samples, duplicates and blank samples were inserted into the sample stream such as to represent approximately 5% of the samples submitted to the laboratory for analysis Two composite samples were collected over three metre intervals – the first (the A sample) being submitted for laboratory analysis and the second (the B sample) being retained as a reference. A sample from each metre was collected and stored in a chip tray for logging and x-ray diffraction analysis Air core drilling was completed by hammer and blade industry standard drilling techniques Aircore is considered to be an appropriate drilling technique for saprolite clay Drilling used blade bits of 87mmØ with 3m length drill rods to blade refusal. Air core recoveries were not recorded but are not considered to be materially biased, given the nature of the geology and samples. The assay data will be analysed against control samples and historical assays for any indications of bias The Competent Person considers that due to the nature of the drilling and geology, sample bias is unlikely to result from poor recovery. All chips were logged qualitatively and quantitatively. A sample from each metre was collected and stored in a chip tray for logging Geological logs recorded lithology, colour and weathering. The Competent Person considers that the logging protocols are sufficient to support estimation of a Mineral Resource. A composite sample of ~ 3kg for analysis was taken using a scoop from each metre pile to subsample 1 to 1.5kg sample. This was then dispatched to the laboratory. A second composite sample was similarly taken and stored on site as a reference Air core samples were a mix of wet and dry Certified reference samples, duplicates and blank samples were inserted into the sample stream such as to represent approximately 5% of the samples submitted to the laboratory for analysis The Competent Person considers to be appropriate the measures taken to demonstrate that sample protocols were appropriate and unbiased. 14 Criteria JORC Code explanation Commentary Quality of assay data and laboratory tests • • • • Verification of sampling and assaying • • • • The natur