Announcement PDF Monday, 28 August 2023 100m STEP OUT HOLE AT KAVANAGH HITS 45.4m @ 1.2% COPPER HIGHLIGHTS • Diamond drilling to test extensions of the main Kavanagh mineral system have returned outstanding results circa 100m from the nearest copper intercept and 70m from the Resource envelope. • The results include: o 45.4m @ 1.19% Cu, 0.12 g/t Au from 428.5m downhole (KTDD243_W1), including: ▪ 5.35m @ 2.13 % Cu, 0.11 g/t Au from 428.5m downhole, and ▪ 23.9m @ 1.53 % Cu, 0.12 g/t Au from 444m downhole, including ▪ 6.6m @2.31% Cu, 0.23 g/t Au from 460.4m downhole. • The drilling demonstrates that the Kavanagh mineral system continues to host wide zones of higher grade Cu-Au breccia within 100m from and adjacent to, the planned Underground (UG) development and which are not included in any current mineral resource estimate. • These drilling results demonstrate the potential to increase the existing mineral resource inventory and would indicate that extensions to the mine life are possible. • These drill intercepts are mainly located within the Spitfire Cu-Au mineral system, at the southern end of the Kavanagh Cu-Au lode. • The Spitfire lodes have not previously been the focus of the surface exploration drilling programs. • The mineralisation in these drill intercepts is open down-dip and open along strike. • Restart of copper production at Kanmantoo, scheduled to commence in Q1 2024, remains on track. For a plan of the location of the drilling, see Figure 4 and for the list of all drill results in this release, see Table 1. Intercepts tabulated in the Highlights table are amalgamated over a minimum down hole length of 2m > 0.3% Cu with a maximum of 2m internal dilution < 0.3% Cu. No assays were cut before amalgamating the intercept calculation. Hillgrove Resources Limited ACN 004 297 116 Ground Floor, 5-7 King William Road, Unley SA 5061, Australia | T + 61 8 7070 1698 | E info@hillgroveresources.com.au Figure 1 Oblique section showing current mine design relative to the new drill holes Spitfire, illustrated in red in Figures 1 and 2, consists of two stope levels in the Economic Assessment Study (EAS) released on 27 February 2023. The recent intersection is further down plunge and along strike of the Spitfire stopes, highlighting an opportunity to extend the mine design in this area (subject to further drilling). Note: Figures 1 and 2 show only the two drill holes (KTDD243 and KTDD243W1). There are other holes that exist but are not shown in order to declutter the images. Figure 2 Long section (looking west) showing current mine design relative to the new drill holes Hillgrove Resources Limited ACN 004 297 116 Ground Floor, 5-7 King William Road, Unley SA 5061, Australia | T + 61 8 7070 1698 | E info@hillgroveresources.com.au Figure 3 Cross section through KTDD243_W1 drill hole Intersection > 80m from known mineralisation provides opportunity to increase mine plan pending future drilling success Hillgrove Resources Limited (Hillgrove, the Company) (ASX:HGO) is pleased to provide the following drilling update at its Kanmantoo Mine Lease located at Kanmantoo, 55kms southeast of Adelaide in South Australia. In total, a further three exploration diamond holes have been drilled to the end of July 2023 for 2,202.6 metres of drilling. Figure 4 shows the locations of these additional 2023 drill holes into the Kavanagh mineral system. Drilling has now been completed and all assays received. Overall, the 2023 drilling continues to successfully increase the mineralisation footprint in the Kavanagh lode system. Hillgrove Resources Limited ACN 004 297 116 Ground Floor, 5-7 King William Road, Unley SA 5061, Australia | T + 61 8 7070 1698 | E info@hillgroveresources.com.au Two of the diamond drill holes (KTDD243 and 243_W1) intersected the Spitfire Cu-Au mineral zone and narrower down-dip extensions of the Central Kavanagh Cu-Au lodes. The Spitfire zone is located <50m south of the Kavanagh UG decline that is currently being developed, and is adjacent to the planned UG access to the Nugent Cu-Au lode system. The two drill holes (KTDD243, and 243_W1) intersected the Spitfire mineralisation at ~420 metres below surface (at ~750m RL) and affirm the down dip continuity of multiple Spitfire Cu-Au zones previously mined in the Giant open pit down to 1000m RL. Further drilling from UG and from surface is warranted to determine the down-dip and along strike extent of these Cu breccia zones. The third exploration diamond drill hole (KTDD244) was planned to intersect an extension of the Central Kavanagh Cu-Au system. The hole intersected multiple wide zones of low grade Cu-Au mineralisation demonstrating the continuation of the system, including a Cu breccia zone of higher grade mineralisation (1.2m @ 2.46% Cu, 0.47 g/t Au). Commenting on the drilling results, Hillgrove CEO and Managing Director, Lachlan Wallace said: “The drilling continues to demonstrate the continuity of the copper mineralisation below the current mine design. The two holes in Spitfire show the potential for Spitfire to extend at least a further 70m down dip, as well as along strike, with the most northern hole in Spitfire returning a downhole drill intersection of over 45m at 1.19% Cu and 0.12 g/t Au, and remaining open to the north. The close proximity of the Spitfire lode to the current underground decline development provides an opportunity to bring these lodes into the early stages of the mine plan for modest incremental cost.” Further details of the drilling are provided in Appendices A and B. Authorised for release by the Board of Hillgrove Resources Limited. For more information contact: Mr Lachlan Wallace CEO & Managing Director Tel: +61 (0)8 7070 1698 Mr Joe Sutanto Chief Financial Officer & Company Secretary Tel: +61 (0)8 7070 1698 Hillgrove Resources Limited ACN 004 297 116 Ground Floor, 5-7 King William Road, Unley SA 5061, Australia | T + 61 8 7070 1698 | E info@hillgroveresources.com.au Competent Person's Statement The information in this release that relates to the Exploration Results is based upon information compiled by Mr Peter Rolley, who is a Member of The Australian Institute of Geoscientists. Mr Rolley is a full-time employee of Hillgrove Resources Limited and has sufficient experience relevant to the styles of mineralisation and type of deposit under consideration to qualify as a Competent Person as defined in the 2012 Edition of the ‘Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (JORC Code)’. Mr Rolley has consented to the inclusion in the release of the matters based on their information in the form and context in which it appears. The information in this report that relates to past Exploration and Drilling Results on the Kanmantoo project were initially reported by the Company to ASX on 26 May 2016, 10 October 2019, 3 September 2020, 3 May 2021, 6 May 2021, 24 June 2021, 26 August 2021, 1 September 2021, 21 March 2022, 6 May 2022, 27 February 2023 and 3 July 2023. The Company confirms that it is not aware of any new information or data that materially affects the information included in the original market announcement and that all material assumptions and technical parameters underpinning the Exploration Results and the Resource Estimate in the relevant market announcement continue to apply and have not materially changed. The Company confirms that the form and context in which the Competent Person's findings are presented have not been materially modified from the original market announcements. Figure 4 Plan View of the location of the 2023-Q2 exploration drilling Hillgrove Resources Limited ACN 004 297 116 Ground Floor, 5-7 King William Road, Unley SA 5061, Australia | T + 61 8 7070 1698 | E info@hillgroveresources.com.au Table 1 Hole ID KTDD243 KTDD243_W1 KTDD244 Ore Zone Target List of drill intercepts in this release Depth From Interval Length Cu% Au g/t Spitfire 398 20.1 0.89 0.2 incl 412 6.1 2.24 0.49 Central Kavanagh 443 4 1.07 0.25 Central Kavanagh 527 2.6 1.26 0.05 Spitfire 428.5 45.4 1.19 0.12 incl 428.5 5.35 2.13 0.11 incl 444 23.9 1.53 0.12 incl 460.4 6.6 2.31 0.23 Central Kavanagh 537 4.3 1.71 0.04 Central Kavanagh 516 1.2 2.46 0.47 Intercepts in Table 1 are amalgamated over a minimum down hole length of 2m > 0.3% Cu with a maximum of 2m internal dilution < 0.3% Cu. No assays were cut before amalgamating the intercept calculation. APPENDIX A The objective of the Q2 2023 diamond drilling program has been the Kavanagh and Spitfire mineral systems within the Kanmantoo Mine Lease. All holes are collared and drilled using conventional HQ/NQ diamond drilling tools and navi-drilling as required to achieve the targets. Figure 4 shows a plan view of the locations of the drill holes. Collar co-ordinates and downhole surveys of the holes reported in this release are provided in Table’s 2 and 3 in Appendix B respectively. Appendix B also describes the drilling techniques and QA/QC processes. Figure 5 provides an example of the Cu-Au breccia zone in KTDD243_W1 at Spitfire from a downhole depth of 464.08m. Note the excellent core recovery. Figures 6 and 7 are cross sections through the Spitfire drill holes. Hillgrove Resources Limited ACN 004 297 116 Ground Floor, 5-7 King William Road, Unley SA 5061, Australia | T + 61 8 7070 1698 | E info@hillgroveresources.com.au Figure 5 Cu-Au mineralisation in KTDD243_W1 through the Spitfire Lode The interval 464.0 to 468.4m shown in this photo is an average of 4.4m @ 2.57% Cu, 0.30 g/t Au. Figure 6 Cross Section through KTDD243 drill hole Hillgrove Resources Limited ACN 004 297 116 Ground Floor, 5-7 King William Road, Unley SA 5061, Australia | T + 61 8 7070 1698 | E info@hillgroveresources.com.au Figure 7 Cross section through KTDD243_W1 drill hole Summary These drilling results, as experienced in every drill program since 2018, continue to demonstrate that drilling is continuing to increase the footprint of the Cu-Au zones at Kanmantoo in preparation for expanding the opportunity for increasing copper production at Kanmantoo. Hillgrove Resources Limited ACN 004 297 116 Ground Floor, 5-7 King William Road, Unley SA 5061, Australia | T + 61 8 7070 1698 | E info@hillgroveresources.com.au APPENDIX B – JORC Table 1 Section 1 Sampling Techniques and Data Criteria Sampling techniques Commentary • The 2023 Diamond Drill Hole (DDH) sampling was conducted as per the Hillgrove Resources procedures and QAQC protocols. • Sample intervals from 1.22m to 0.25m as determined by geology through visibly mineralised zones were split from the drill core, with the drill core sawn in half with a diamond core saw. • Samples were prepared by ALS Adelaide with each sample being wholly pulverised to >85% passing <75µm. Drilling techniques • All drilling undertaken by external drilling contractor, DRC Drilling. Using HQ for collars to a maximum of 321.4m downhole and NQ drilling thereafter for all drilling holes. NQ Core size is 47.6mm in diameter. Drill sample recovery • Recovered drill core metres were measured and compared to length of drill hole advance to calculate core recovery for every core run. On average sample recovery is >98%. There is no correlation between sample recovery and copper grades in this DDH drill program. Logging Sub-sampling techniques and sample preparation • All drill core was logged for lithology, alteration, weathering and mineralisation by Hillgrove geologists in accordance with Hillgrove’s Core Logging Procedure. Colour and any additional qualitative comments were also recorded. • High quality photographs of all drill core before being sampled were taken under controlled light at the HGO core yard at Kanmantoo. • All drill core is stored at Hillgrove’s Kanmantoo core yard facility. • All geological logging is recorded into LogChief (a database product from Maxwell Geosciences) templates and visually validated before being imported into the Hillgrove drill hole database. Additional validation is conducted automatically on import. • In addition, a structural log of all drill core is recorded utilising the “base of core” orientation mark collected during diamond drilling to assist in understanding the local controls on the mineralisation. • A geotechnical log of all drill core for UG mine planning is also recorded. RQD is 98-100% • For selected intervals the core was sawn in half and the half core despatched to ALS for each sample interval and the entire sample then crushed and 1kg riffle split from the crushed mass and the 1kg sub-sample then pulverised. A sub-split of 200 grams was then split by ALS and retained, and the reject pulverised material returned to Hillgrove. From the 200 gram sub-split a 2 gram aliquot was scooped and weighed by ALS for 4-acid digestion. Hillgrove Resources Limited ACN 004 297 116 Ground Floor, 5-7 King William Road, Unley SA 5061, Australia | T + 61 8 7070 1698 | E info@hillgroveresources.com.au Criteria Commentary • Hillgrove have detailed sampling and QAQC procedures in place to ensure sample collection is carried out to maximise representivity of the samples, to minimise contamination, and to maintain sample numbering integrity. Quality of assay data and laboratory tests Verification of sampling and assaying • All samples were submitted to ALS for analysis. ALS code ME-MS61 using a 4-acid digest with determination by Mass Spectrometry. If the copper result was greater than 1%, the analysis was repeated using a modified acid digestion technique. • Gold is assayed by 30g Fire Assay. If > 10 g/t then repeated by fire assay with a gravimetric finish • The QAQC of sample preparation and analysis processes were via the following samples: o Certified reference materials (CRM’s) inserted by HGO into the sample sequence at a frequency of one in 20. OREAS standard 506 has been used to provide a CRM Standard grade of 0.444% Cu, and 0.365 g/t Au which are relevant for the expected cutoff grades used for resource estimates across the Kanmantoo deposit. o Results from all returned QAQC samples provide reasonable confidence as to the accuracy of the assay results used in the estimation. >90% of assays fall within 2SD of the expected CRM mean grade for Cu and Au. o Laboratory inserted QAQC samples were inserted with a minimum of two standards and one blank for every batch of 40 samples. • Quartz flushes with <60ppm Cu are introduced to the bowl pulverisers within every high sulphide interval. These are monitored and where Cu contamination of the quartz flush occurs the batch is repeated by the assay lab. For the holes reported there are no examples of sulphides contaminating successive samples via sample preparation processes. • Quartz washes are also utilised through the Boyd crusher where high sulphides are present and identified by the logging geologist to ALS. • Hillgrove‘s quality policy is that at a minimum of 5% of all samples are CRM’s, and 5% of samples submitted are blanks thus ensuring that as a minimum, 10% of all samples submitted for analysis are Hillgrove QAQC samples. • Sample data sheets are prepared in Log Chief and printed for technicians use. All core is marked for sampling and confirmed by the logging geologist. Sample Sheets also include the sample number sequence and the sample numbers to be assigned to the QAQC samples. Sample intervals input from the excel spreadsheet into an SQL database via Datashed. Data was visually checked by the Geologist prior to import and additional validation was carried out by the database upon import. Copper results were reported in ppm units from the laboratories and then converted to a % value within the database. Hillgrove Resources Limited ACN 004 297 116 Ground Floor, 5-7 King William Road, Unley SA 5061, Australia | T + 61 8 7070 1698 | E info@hillgroveresources.com.au Criteria Location of data points Commentary • The map projection of Map Grid of Australia 1994 - Zone 54, (MGA94-54) was used for all work undertaken for this drilling. • All drill hole collars were surveyed with a Trimble survey station. The accuracy of this instrument is 0.01m. All pick-ups were reported in MGA94-54 coordinate system. • Downhole surveys were determined using a gyro survey instrument at 12m intervals and recorded in Grid North. All holes were repeat surveyed for verification. Table 2 Collars of the drill holes reported in this document (MGA94_Zone 54) Table 3 Downhole survey data for the drill holes reported in this document (Azimuth is MGA94 Grid) Hillgrove Resources Limited ACN 004 297 116 Ground Floor, 5-7 King William Road, Unley SA 5061, Australia | T + 61 8 7070 1698 | E info@hillgroveresources.com.au Hillgrove Resources Limited ACN 004 297 116 Ground Floor, 5-7 King William Road, Unley SA 5061, Australia | T + 61 8 7070 1698 | E info@hillgroveresources.com.au Criteria Commentary Data spacing and • See Table’s 2 and 3 above and Figures 4, 6 and 7 in the body of the text for drill hole locations. distribution Orientation of data in relation to geological structure Sample security Audits or reviews • • • • • All holes are angled drill holes, dipping between -69 to -33deg. All holes are oriented towards 270-301deg (MGA Grid North). All down hole surveys are by Reflex or Axis Gyro All core is oriented with a Reflex orientation tool where possible to do so. Dominant mineralisation trends as measured from in-pit mapping are strike 015deg and dip -75deg to east. It is important to note that current drill holes are all at various strike and dip angles to section, and that the true width varies for each intersection. • A Hillgrove employee is present for the collection of core trays from the DDH rig and is also responsible for collecting and organising the samples ready for assay. Hillgrove has a detailed sample collection/submission procedure in place to ensure sample security. • Drill core is transported in covered trays from the drill site to Hillgrove’s core yard at Kanmantoo in Hillgrove vehicles under the supervision of Hillgrove staff. • Transport of the half-sawn drill core samples is by dedicated road transport to the Adelaide sample preparation facility. All samples are transported in sealed plastic bags and are accompanied by (either paper form or by email) a detailed sample submission form. • On receiving a batch of samples, the receiving laboratory checks received samples against a sample dispatch sheet supplied by Hillgrove personnel. On completion of this check a sample reconciliation report is provided for each batch received. • There has not been an external review of this DDH drilling program. Previous audits of the Hillgrove sampling methods were reviewed by independent consultant and were considered to be of a very high standard. Hillgrove Resources Limited ACN 004 297 116 Ground Floor, 5-7 King William Road, Unley SA 5061, Australia | T + 61 8 7070 1698 | E info@hillgroveresources.com.au Section 2 Reporting of Exploration Results Criteria Mineral tenement and land tenure status Exploration done by other parties Geology Commentary • The Kanmantoo Cu-Au mine is situated on Mining Lease ML6345 and is owned 100% by Hillgrove Resources Limited (HGO). • HGO owns the land covered by the Mining Lease. The Mine Lease is encompassed on all sides by EL6526 also owned 100% by Hillgrove Resources. All drill holes were drilled on land owned or rented by Hillgrove Resources. • Hillgrove Resources commenced exploration drilling in 2004 and since then has completed a number of exploration sampling and mapping campaigns which have resulted in defining the drill targets. • Mineralisation occurs as an epigenetic system of structurally controlled veins and disseminations of chalcopyrite, pyrrhotite, pyrite, magnetite, within a quartz + biotite + andalusite ± garnet ± chlorite +/- staurolite schist host rock. Structural studies suggest the mineralisation is within brittle structures that have been re-activated. Drill hole Information • Drill collars, surveys, intercepts are reported in the body of this release. Data aggregation methods • Intercepts tabulated in the body of the report are amalgamated over a minimum down hole length of 2m > 0.3% Cu with a maximum of 2m internal dilution < 0.3% Cu. No assays were cut before amalgamating for the intercept calculation. Mineralisation widths • Table of downhole mineralised intercepts is reported in the body of this release. Diagrams • Diagrams that are relevant to this release have been included in the body of the release. Balanced reporting • All drill holes have been reported. Other exploration data • Insitu rock density has been measured by wet immersion method. The results indicate that the bulk rock density of 3.1t/m3 as used at the Kavanagh mine site is still a reasonable representation of bulk density for all mineralisation. Further work • Geological interpretation of the geology and assays to estimate a resource suitable for underground evaluation studies. Hillgrove Resources Limited ACN 004 297 116 Ground Floor, 5-7 King William Road, Unley SA 5061, Australia | T + 61 8 7070 1698 | E info@hillgroveresources.com.au