Mt Cattlin Ore Reserve update confirms mine life extension

A total of 39 DD holes for 1,528.56m, 986 RC holes for 48,763m,59 OH holes for 1,999m and 23 RAB for 402m had been completed before 2017. 

The drill-hole collars were surveyed by professional survey contractors. A total of 71 drill holes were surveyed by Surtron Technologies Australia of Welshpool in 2010. Sampling was carried out under Galaxy Resources QAQC protocols and as per industry best practice. 

RC sample returns were closely monitored, managed and recorded. Drill samples were logged for lithology and SG measurements. Diamond HQ and PQ core was quarter-cored to sample lengths relating to the geological boundaries, but not exceeding 1m on average. RC samples were composited from 1m drill samples split using a two-stage riffle splitter 25/75 to obtain 2kg to 4kg of sample for sample preparation. All samples were dried, crushed, pulverized and split to produce a 3.5kg and then 200g sub-sample for analysis For Li (method AAS40Q), for Ta, Nb and Sn (method XRF78O) and in some cases for SiO2, Al2O3, CaO, Cr2O3, Fe2O3, K2O3, MgO, MnO, P2O5, SO3, TiO2 and V2O5 were analysed by XRF78O. Entire drill-hole lengths were submitted for assay.  

Drilling 2017-8 
From 1m of drilling and sampling, two 12.5% splits are taken by a static cone splitter in calico drawstring bags. This obtains two 2kg to 4kg samples with one being retained as an archive sample and the other submitted for assay, where required an archive bag is used as the duplicate sample. 

A 4.5-inch diameter rod string is used and the cyclone is cleaned at the end of every 6m rod as caking occurs from the mandatory use of dust suppression equipment. 

Drilling November 2018 – 2021 
Subsequent to 2018 update, 5,912m (41 holes) of new reverse circulation (RC) and 273.65m of diamond tails (2 holes)  has been completed (excluding metallurgical and geotechnical) has taken place.

From 1m of drilling and sampling, two 12.5% splits are taken by a static cone splitter in calico drawstring bags. This obtains two 2kg to 4kg samples with one being retained as an archive sample and the other submitted for assay, where required an archive bag is used as the duplicate sample.

A 4.5-inch diameter rod string is used and the cyclone is cleaned at the end of every 6m rod as caking occurs from the mandatory use of dust suppression equipment. 

2022 Drilling
The current drillhole dataset for the project contains 3,232 drillholes, for 175,950 metres, comprised of a combination of reverse circulation (RC), diamond drilling (DD), and RC with a diamond tail (RC_DDT) drillholes.

The dominant drillhole type is RC, with over 95% of the metres being from RC drillholes.

RC 2017 -2020 
5.25-inch face sampling hammer, reverse circulation, truck mounted or tracked drilling rigs, Three Rivers Drilling, Castle Drilling. 

Diamond core is generally RC from surface, and either PQ size tails in weathered rock and narrowed to HQ in fresh rock (standard tubing). Core was not oriented as the disseminated and weathered nature of the mineralization does not warrant or allow it. Diamond core is typically for metallurgical test-work.  Pre-collars drilled short of mineralisation. 

RC 2021 A 5.25-inch face sampling hammer, used in reverse circulation. ASX (Australian Surface Exploration) drillers used for RC (including pre-collars).

Diamond 2021: 
Wizard Drilling utilised for diamond drilling from surface. HQ size Metallurgical and geotechnical diamond drilling (standard tubing). Two Metallurgical holes were diamond tails from approximately 70m to 80m. Four Geotechnical holes were diamond from surface and two tails from 50-60m depth.

RC 2022
PXD drilling was utilised for RC drilling from surface.  HQ size Metallurgical and geotechnical diamond drilling (standard tubing) by Orlando Drilling. Four Metallurgical holes were and three Geotechnical holes were diamond drilled from surface and two diamond tails from 150-160m depth.

The DD core was oriented using the Ezy-Mark tool and after 2019 using the Reflex ACT electronic orientation tool. 
Geological logging was qualitative. 

Recording of interval weights, recovery and RQD was quantitative. 
All DD core was photographed and representative 1m samples of RC and OH (PC) chips were collected in chip trays for future reference and photographed. All drill holes were logged in full.

2017-2023 logging 
All drill holes are logged and validated via LogChief/ Maxwells Geosciences/DataShed systems. 
Assays, standards and control limits are monitored after loading of each batch and reports supplied on demand.  All drill holes are logged in full.  Different Lithium bearing mineral species are logged in detail.

All 2kg 1m drill samples were sent to SGS, dried, crushed, pulverized and split to approximately -75µ to produce a sample less than 3.5kg sub-sample for analysis. 

Sampling was carried out under Galaxy Resources QAQC protocols and as per industry best practice. 

Duplicate, blank and standard reference samples were inserted into the sample stream at random, but averaging no less than 1 blank and standard in every 25 samples. 

Samples were selected periodically and screened to ensure pulps are pulverized to the required specifications. 

Duplicate quarter-core samples were taken from DD core at random for testing averaging one in every 25 samples. 

Duplicate riffle-split RC samples were taken at random, but averaging one every approximately 25 samples. 

The sample sizes are appropriate to the style, thickness and consistency of the mineralization at Mt Catlin. 

Drilling 2016 (SGS) 
Core was halved by saw and sample lengths typically 0.5m in length. Sample preparation involved crushing followed by splitting of sample if sample greater than 3 kg using a riffle splitter (SPL26), Dry sample, crush to 6mm, pulverise to 75µm (PRP88) in a LM5 Mill.

Drilling 2017-2021  
Diamond drilling was typically sawn half core with whole core used for metallurgical test work. 

Intertek (2017-8) 
Samples are sorted and weighed. Samples >3kg are riffle split and milled in LM5 to obtain 85% passing 75 Microns. A 400g pulp is taken and a nominal 0.25g sub-sample is fused with sodium peroxide. 

Nagrom:  2018-2021 
RC chips are dried to 105C°, crushed to nominal top-size of 2 mm in a Terminator Jaw crusher using method CRU01. Pulverised up to 3 kg in a LM5 pulveriser mill at 80% or better passing 75µm, using method PUL01.  If the sample is greater than 3 kg, the sample is dried, and split with rotary splitter before analysis, Diamond core is dried, crushed in a Terminator Jaw crusher to top size 6.3 mm, and pulverised in a LM5 mill up to 2.5 kg using method CRU01.  If the sample is greater than 2.5 kg, the sample is riffle split after drying to reduce the sample size.

Intertek 2022-3
Samples are sorted and weighed. Samples >3kg are riffle split and milled in LM5 to obtain 85% passing 75 Microns. A 400g pulp is taken and a nominal 0.25g sub-sample is assayed by Sodium peroxide fusion in a Ni crucible / MS, OES method FP6-Li/OM19.

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 (e.g. standards, blanks, duplicates, external laboratory checks) and whether acceptable levels of accuracy (i.e. lack of bias) and precision have been established.

Duplicate, blank and certified reference samples were inserted into the sample stream at random, but averaging one every ~25 samples. Galaxy Resources utilized certified Lithium standards produced in China and one from SGS in Australia, STD-TAN1. 

Inter-laboratory checking of analytical outcomes was routinely undertaken to ensure continued accuracy and precision by the preferred laboratory. 
Samples were selected periodically and screened by the laboratory to ensure pulps are pulverized to the required specifications. All QAQC data is stored in the Mt Catlin database and regular studies were undertaken to ensure sample analysis was kept within acceptable levels of accuracy; the studies confirmed that accuracy and precision are within industry standard accepted limits. 

Umpire analysis performed on pulps at Genalysis and Ultratrace Perth 

2016-QAQC 
In 2016 Perth SGS were used for a small 6 hole diamond program by General Mining. Samples were digested using a sodium peroxide fusion digest, method DIG90Q and the resultant solution from the digest was then presented to an ICP-MS for the quantification of Li2O, using method IMS40Q. The majority of standards submitted performed within expected ranges with a positive bias observed for two standards.

2017 – 2021  QAQC
Samples (including QA/QC samples) were processed by Intertek PLC, Perth laboratory in 2017 and 2018, by utilised method FP1 digest (Peroxide Fusion – complete), MS analytical finish, 22 elements, Li2O detection limit 0.03% Ta2O5 detection limit, 0.2 ppm. Monthly review of QA/QC, which includes blanks, field duplicates, high grade standards and CRM (certified reference materials) and SRM (standard reference materials). FS_ICPMS is a Laboratory Method FP1/MS (mass spectrometry) used to analyse for Cs, Nb, Rb, Ta,Th, and U . FS/ICPES (inductively coupled plasma emission spectroscopy) is Laboratory method FP1/OE used to analyse Al, Fe, K, Li, and Si. Reports include calculated values of oxides for all elements.

RC samples and diamond (including QA/QC samples) have been processed by Nagrom Perth, Perth Western Australia. Methods utilised from Lithium and Tantalum are ICP004 and ICP005 (Peroxide Fusion – complete). ICP005 utilises tungsten carbide bowl to reduce iron contamination at exploration and resource development stages (detection limit of 10ppm and 1ppm for Li2O and Ta respectively) Monthly review of QA/QC, which includes blanks, field duplicates, high grade standards and CRM (certified reference materials) and SRM (standard reference materials). All sampling has rigorous QAQC in terms of reference sampling as well as blank and standards introduced into the sample steam. 
Duplicate field samples show some evidence of high nugget effect. Typically, duplicate pairs plot within acceptable limits. Field duplicates have been submitted at a rate of 1 per 20.5 samples.

Standards used are ASM0343, ASM0340 AMIS0339, OREAS147, OREAS148 and OREAS149. 

Standards reported only one result outside three standard deviations from 533 assays for Lithium. The majority of Tantalum standards reported within three standard deviations. 

Coarse blanks have shown no evidence of systematic contamination from 2016-2021 with results consistently low. 

QAQC in 2022-3 is broadly in line with the processes above, assays are by Intertek, Perth and Kalgoorlie.

Standards used are OREAS 147, AMIS0341, OREAS 751, OREAS 753, OREAS 148, AMIS0341, AMIS0341, and OREAS 147 to support Sodium peroxide fusion in Ni crucible assay method MS, OES FP6-Li/OM19. This method provides near complete recovery for most samples.

Ore grade standards e.g. Oreas 751 reported only four results outside 2 standard deviations from assays for Lithia. The majority of Tantalum standards reported within 2 standard deviations.

A figure accompanying this announcement is available at https://www.globenewswire.com/NewsRoom/AttachmentNg/a0a96d56-0609-4c98-a4b7-54a5abe86952

The data is moderately precise.

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.

The geological logging of the DD holes supports the interpreted geological and mineralization domains. 

Studies on assays results from twinned holes showed a close correlation of geology and assays. 

Primary data is recorded by hand in the field and entered Excel spread sheets with in-built validation settings and look-up codes. 
Scans of field data sheets and digital data entry spread sheets are handled on site at Mt Cattlin. 
Data collection and entry procedures are documented, and training given to all staff. 

QAQC checks of assays had identified several standards out of control, these were subsequently reviewed and results rectified. 

No clear and consistent biases were defined by Galaxy during the further investigations into QAQC performances although deviations were noted by Galaxy. 

2017-8 Verification 
CP independently verified drilling, sampling, assay and results from validated, externally maintained and stored database. 
No adjustments to assay data other than conversion from Li to Li20 and Ta to Ta2O5.

2018 – 2022 Verification
The CP independently verified drilling, sampling, assay and results from validated, externally maintained and stored database. 
No adjustments to assay data other than conversion from Li to Li20 and Ta to Ta2O5. 

Primary data capture by Maxwell LogChief and management by Maxwell DataShed.  Assay data loaded directly from Laboratory supplied .csv files as are downhole and collar surveys.

An independent data verification was completed as part of a 2021 Ni-43-101 filing by then competent person.

Data exported from SQL database and verified by the CP.

No adjustments are made to assay data.

• 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 license to operate in the area. 

The project is subject to normal projects approvals processes as regulated by the WA Department of Mines, Industry and Regulation.

The tenement is subject to the Standard Noongar Heritage agreement as executed 7 February 2018.

The underlying land is a mixture of freehold property and vacant Crown land. The property Freehold title is held by Galaxy Resources or its child subsidiaries.

• Acknowledgment and appraisal of exploration by other parties.

In 1989 Pancontinental Mining, Limited drilled 101 RC drill holes. In 1990 Pancontinental drilled a further 21 RC drill holes. 

In 1997 Greenstone Resources drilled 3 diamond holes and 38 RC holes, undertook soil sampling and metallurgical test work on bulk samples from the mine area.

Haddington Resources Ltd in 2001 drilled 9 diamond holes for metallurgical test work and undertook further sterilization drilling. 

Galaxy acquired the M72/12 mining tenement from the Sons of Gwalia administrators in 2006. 

• Deposit type, geological setting and style of mineralization. 

The Annabelle Volcanics at Mt Cattlin consist of intermediate to mafic volcanic rocks, comprising both pyroclastic material and lavas. 

The pegmatites which comprise the orebodies occurs as a series of sub- horizontal sills, hosted by both volcanic and intrusive rocks, interpreted as a series of westward verging thrusts. Typical coarse grained spodumene (grey green colour) from the NW pegmatite shown below.

A photo accompanying this announcement is available at https://www.globenewswire.com/NewsRoom/AttachmentNg/f75c30db-a3c7-4a94-b77e-7e2fe8863892
   

• 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: 
  • easting and northing of the drill hole collar 
  • elevation or RL (Reduced Level – elevation above sea level in meters) of the drill hole collar 
  • dip and azimuth of the hole 
  • down hole length and interception depth 
  • hole length. 

2019-2022 drill collars 
New resource development collar information is presented in Appendices below.

Holes generally inclined between -75 to -80 degrees to determine true width or due to local infrastructure.

• In reporting Exploration Results, weighting averaging techniques, maximum and/or minimum grade truncations (e.g. 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. 

2019-2022 Drilling 
New results are reported to a 0.3% cut-of grade (below), minimum 4m width, maximum 1m internal dilution.  Only drillholes incorporated into the resource model are reported. 

No metal equivalent values are used. 

• These relationships are particularly important in the reporting of Exploration Results. 
• If the geometry of the mineralization 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’). 

Intersections were calculated allowing a maximum of 2m of internal dilution with no top-cut applied. Cutting of high grades is not required due to nature of the mineralization and grade distribution/estimation. 

The Mt Cattlin lithium and tantalum mineralization occurs as a thick horizontal to gently dipping pegmatite and generally lies 30 to 280m below the current topographic surface resulting in drill intercepts nearing true widths.

All reported intersections in 2023 are approximate true widths.

• 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. 

• 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. 

2019-2022 Drilling 
Drill hole collars and relevant assay details are appended below.

• Other exploration data, if meaningful and material, should be reported including (but not limited to): geological observations; geophysical survey results; geochemical survey results; bulk sample– size and method of treatment; metallurgical test results; bulk density, groundwater, geotechnical and rock characteristics; potential deleterious or contaminating substances. 

• 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.

Diagrams are illustrated in the text above.

Feasibility study work to trade off open pit vs underground options has commenced.

• 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.

Field data was entered into project-specific password-protected spread sheets with in-built auto-validation settings. The spread sheets were emailed to head office on a weekly basis and then passed on to the data administrator, where all data was subject to validation procedures and checks before being imported into the central database. Invalid data was not imported into the central database but was quarantined until corrected. Data exports were routinely sent from head office to site for visual validation using ArcGIS and Micromine.

2017 to Jan 2019
Database and data QAQC processes was re-established after review in 2016. The Datashed database was managed/maintained by Maxwell Geoservices and was validated externally to GXY and aggregated meta-data from site and the sample laboratory. The assay laboratory reported sample validation and checks on arrival. Database managers’ reported both QAQC and validation checks monthly and upon request.

Jan 2019 to Current
Allkem have employed a Database Administrator who loads all data, manages the database and performs routine validations on all loaded data.

All logging is undertaken on a Toughbook using the dedicated LogChief logging system matched to the Datashed database.

Visual validation of drilling data versus the wireframes in Surpac software is undertaken routinely by Mine Geology and Exploration personnel.

• 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.

• 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.

Surface diamond and reverse circulation (RC) drillholes have been logged for lithology, structure, and alteration and mineralisation data.

The lithological logging of pegmatite in combination with the Li₂O, Fe₂O₃ and MgO assays, including grain size and mineralogical differentiation, have been used to guide the sectional interpretation of the pegmatites in Leapfrog Geo modelling software.

The geological wireframes have then been used as a boundary within which internal, mineralisation wireframes have been generated in Leapfrog software using geology logging and assay data. The primary assumption is that the mineralisation is hosted within the fine-grained material within the pegmatite sills, which is considered robust.

Weathering surfaces have been updated by Allkem Resources in Leapfrog Geo software for recently completed drillholes.

Due to the consistent nature of the pegmatite identified in the area, no alternative interpretations have been considered. The pegmatites are found to be continuous over the area of the deposit.

The Li₂O% mineralisation interpretations are contained wholly within the pegmatite geological units. Evidence of late-stage faulting is present and has, where appropriate, been incorporated into the geological model.

• 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

Thirteen pegmatites have been identified to date in the NW and SW area. They range in extent from 50 m along strike and 50 m down-dip to 650 m along-strike and 500 m down-dip. The pegmatites range in thickness from a few metres to 20 m.

• 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 (e.g. 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 drillhole data, and use of reconciliation data if available.

The geological, mineralisation and weathering wireframes generated have been used to define the domain codes by concatenating the three codes into one. The drillholes have been flagged with the domain code and composited using the domain code to segregate the data. Hard boundaries have been used at all domain boundaries for the grade estimation Pegmatite waste wireframing using <0.3% lithia and < 4% Na2O.

Compositing has been undertaken within domain boundaries at 1m with a merge tolerance of 0.1 m.

Top cuts for all elements have been assessed for all mineralised and un-mineralised pegmatite domains, as well as for the external waste and mafic dyke domains, with only those domains with extreme values having been top cut. The top cut levels have been determined using a combination of histograms, log probability and mean-variance plots. Two domains have been top cut for Li₂O. Three domains have been top-cut for or Ta₂O₅ ppm and no top-cutting completed in Fe₂O₃%.

Variography has been completed in Supervisor 8.14 software on an individual domain basis. Domains with too few samples have borrowed variography.

No assumptions have been made regarding the recovery of any by-products.

The drillhole data spacing ranges from 40 m by 40 m resource definition drillhole spacing out to an 80 m by 80 m exploration spacing.

The block model parent block size is 20 m (X) by 20 m (Y) by 5 m (Z), which is considered appropriate for the dominant drillhole spacing used to define the deposit. A sub-block size of 2.5 m (X) by 2.5 m (Y) by 0.625 m (Z) has been used to define the mineralisation edges, with the estimation undertaken at the parent block scale.

• Pass 1 estimations have been undertaken using a minimum of 7 and a maximum of 27 samples into a search ellipse set at approximately half of the variogram range. A 4 sample per drillhole limit has been applied in all pegmatite domains.
• Pass 2 estimations have been undertaken using a minimum of 7 and a maximum of 27 samples into a search ellipse set at approximately the variogram range. A 4 sample per drillhole limit has been applied in all pegmatite domains.
• Pass 3 estimations have been undertaken using a minimum of 2 and a maximum of 24 samples into a search ellipse set at four times the Search 2 range.

The Mineral Resource estimate has been validated using visual validation tools combined with volume comparisons with the input wireframes, mean grade comparisons between the block model and composite grade means and swath plots comparing the composite grades and block model grades by Northing, Easting and RL.

Mining reconciliation data for the NW and SW regions is available.

No selective mining units are assumed in this estimate.

No correlation between variables has been assumed.

• Whether the tonnages are estimated on a dry basis or with natural moisture, and the method of determination of the moisture content.

• The basis of the adopted cut-off grade(s) or quality parameters applied

• 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 mining assumptions/parameters applied to the optimisation are:

• Mining Recovery – 93%
• Mining Dilution – 17%
• Li2O% Price/tonne 6% concentrate – USD$1,100
• Li2O% recovery – 75%
• Ta2O5ppm Price/pound concentrate – USD$40
• Ta2O5ppm recovery – 25%
• Transport and port Cost/tonne – AUD$49.68
• State Royalty – 5%
• Processing Cost/tonne – AUD$33.16
• Mining Cost/tonne – AUD$4.29

USD exchange rate of 0.70 Li₂O cut-off of 0.4% has been applied in the Whittle optimisation.

Both Inferred and Indicated Mineral Resource classifications have been utilised in the RPEEE optimisation.

• 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.

• 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

• 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.

The bulk densities which have been assigned to the Mineral Resource block model by lithology and weathering state are:

• The basis for the classification of the Mineral Resources into varying confidence categories
• Whether appropriate account has been taken of all relevant factors (i.e. 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.

The classification takes into account the relative contributions of geological and data quality and confidence, as well as grade confidence and continuity.

Portions of the deposit which have been estimated in the first two estimation passes and which have been estimated with a high degree of confidence, with defined grade continuity, have been classified as Indicated Mineral Resources.

Portions of the deposit that have been estimated and have a suitable level of drilling to assume geological continuity of the pegmatite have been classified as Inferred Mineral Resources.

The classification reflects the view of the Competent Person.

• The results of any audits or reviews of Mineral Resource estimates.

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

The remaining Measured, Indicated, and Inferred material from the NW and SW region have been considered in the mineral resource.

The estimate is domained by identified pegmatite number and zoned by mineralised and un-mineralised subtypes using 0.3% lithia and Na2O < 4%.

Estimates are thus local by domain.

The same geological model and wireframes are used for grade control and mine planning in Dassault/Surpac Software.

Regularized translations of the original Datamine Studio model are used in Dassault/Surpac re-blocked to 5 x 5 x 6.25m for short term mine planning and monthly reconciliations.

Reconciliation is within tolerance for an “Indicated” resource.

• Regularised mining model created from the MRE that included dilution and mining recovery
• Surveyed surface topography provided from Mt Cattlin as at 31/03/23
• Contract mining costs from a competitive tender process
• Closure costs from the site Mine Closure Plan cost estimate
• Spodumene concentrate (SC5.2) revenue price of US$1,500/t inclusive of shipping and marketing costs
• Tantalite concentrate revenue from current sales contract
• State Government and third-party royalties
• Processing, General & Administration, concentrate surface haulage, and port costs from current site budgets and forecasts (based on actual data)
• Net Present Value (NPV) discounting rate of 10%

Where supplied by Allkem, these input parameters were reviewed by Entech and considered appropriate for the current spodumene concentrate market. 
The staged pit design and schedule is considered suitable for Ore Reserve estimation.

• 20 m bench height 
• 70^o bench face angle 
• 8.5 m wide spill berm 
• 52^o inter-ramp angle 
• 12 m wide geotechnical berm every approx. 100 m of high wall face 

Pit designs were reviewed by Entech’s Principal Geotechnical Engineer to ensure compliance with geotechnical intent.  
In conjunction with the Mineral Resource and grade control predictive computerised block models, established site grade control procedure utilises visual inspection of blast hole cuttings and pit-floor visual geological control when mining ore (“ore spotting”). The combination of techniques enables identification and segregation of barren pegmatite or pegmatite containing fine grained spodumene, from pegmatite containing coarse grained spodumene (ore). Specific grade control drilling campaigns (RC technique) are used in areas of higher structural or mineralogical uncertainty. 
Mt Cattlin is an operating mine with current production and excavation knowledge. The resource drilling that defines the Stage 4 expansion is +95% Reverse Circulation (RC), and predominantly spaced at 40 m x 40 m.

• Regularising the block size into Selective Mining Unit (SMU) dimensions of 5.0 m x 5.0 m x 2.5 m (East, North, Elevation). 
• The SMU size was selected based on the size of the equipment, the parent and sub cell block sizes in the resource model and matched the existing mining bench height to the vertical dimensions of the block. 
• The ore blocks were flagged as either “Clean” (uncontaminated with mining dilution) or “Contaminated” (contaminated with basalt country rock and requiring beneficiation by optical sorting prior to being processed) ore types depending upon the proportion of clean ore within the SMU block.  
• The overall model reports 82% of the ore to the Clean category and 18% to the Contaminated category. 

• contract mining costs – competitive market tender
• all other operating costs – from analysis of the site FY24 forecast (which is derived from actual historical costs and existing contracts) 

Transport charges are derived from existing contracts, and likewise penalty charges are taken from existing sales contracts.

• Environmental Policy 
• Requirements of approvals, permits and licences 
• Environmental responsibilities of site personnel 
• Site induction programmes 
• Environmental monitoring and reporting requirements 
• Inspection and audit process  
• Non-conformance, corrective action, and risk management of incidents 
• Preparation of procedures and work instructions addressing identified elements such as dewatering, saline spillage, waste management and bioremediation 
• Stakeholder consultation, including: 
• Regular update meetings with Shire of Ravensthorpe and Ravensthorpe Business Association 
• Ongoing consultation with local neighbours 
• Ongoing consultation with Traditional Owner groups and presentations at the Southwest Aboriginal Land and Sea Council working party meetings 
• Appointment of an Environmental and Community Liaison Officer 
• Biannual presentations to the Ravensthorpe community 
• Establishment of the Mt Cattlin Community Consultation Group in 2018 with members consisting of respected leaders of the community and Mt Cattlin senior management. Minutes of meetings and presentations are made publicly available via

Allkem have advised the Competent Person that there are no current issues that would be expected to endanger the ‘social licence to operate’.

Historically disproportionate amounts of fine-grained ore in the ROM feed negatively affected plant recovery in the second half of 2022. This has since been identified in the Mineral Resource and domained out of the new MRE which underpins this ORE.