Greatland Resources Limited

E: [email protected]

W: https://greatland.com.au

NEWS RELEASE | 29 June 2026

THIS ANNOUNCEMENT CONTAINS INSIDE INFORMATION AS STIPULATED UNDER THE UK MARKET ABUSE REGULATIONS.  ON PUBLICATION OF THIS ANNOUNCEMENT VIA A REGULATORY INFORMATION SERVICE, THIS INFORMATION IS CONSIDERED TO BE IN THE PUBLIC DOMAIN.

Reserves grow 62% to 5.0Moz

First phase of drill program delivers 150% increase in Telfer Reserve to 1.8Moz

Ongoing investment in drilling and studies is targeting significant further growth

Greatland Resources Limited (Greatland or Company) (ASX:GGP, AIM:GGP) is pleased to provide its Group Ore Reserve Estimate (ORE), as at 31 March 2026 (March 2026 Group Ore Reserve).

The March 2026 Group Ore Reserve incorporates updates at Telfer and the Havieron ORE as reported in December 2025¹. Greatland's substantial Telfer drilling campaign and technical evaluation work is ongoing. Hence, the March 2026 Group Ore Reserve does not include the West Dome Underground (WDU) project and the Vertical Stockwork Corridor (VSC, below the historic sub-level cave), with both in Resource, but subject to ongoing studies.

Telfer's updated ORE is based on the December 2025 Mineral Resource statement² which, in turn, was compiled from approximately the first half of the forecast 240,000m FY26 drill program. This ORE successfully establishes a substantial baseload reserve underpinning an initial multi-year mine life. Going forward, sustained high cadence Telfer drilling is intended to drive further Resource and Reserve growth, with a particular focus on enhancing grade while working towards a multi-decade Telfer-Havieron mine life.

Key highlights:

§ Group Ore Reserve grows to 5.0Moz

-   157Mt at 0.99g/t Au & 0.12% Cu for 5.0Moz Au & 196kt Cu

§ Telfer Ore Reserve increases by 1.1Moz to 1.8Moz (+150%), after depletion

-   119Mt at 0.46g/t Au & 0.06% Cu for 1.8Moz Au & 68kt Cu

-   Multi-year base load reserve secured with 90.6Mt at West Dome Open Pit plus 22.5Mt of stockpiles. Ongoing drilling is targeting further open pit conversion and growth

-   Main Dome Underground reserve of 3.6Mt confirms multi-year mine life extension of existing mining areas, supporting ongoing focus on underground expansion with WDU and VSC opportunities subject to ongoing studies

§ West Dome Open Pit (WDO) Ore Reserve increases by 1.1Moz to 1.4Moz (+375%)

-   90.6Mt at 0.46g/t Au & 0.05% Cu for 1.4Moz Au & 45kt Cu

§  Higher grade component of 70.8Mt at 0.53g/t Au & 0.05% Cu for 1.2Moz Au

§ Main Dome Underground (MDU) Ore Reserve of 0.2Moz gold (previously nil)

-   3.6Mt at 1.33g/t Au and 0.31% Cu for 0.2Moz Au & 11kt Cu

§ Telfer stockpiles provide operational flexibility and contingency

-   22.5Mt at 0.36g/t Au & 0.05% Cu for 0.3Moz Au & 11kt Cu

§ Telfer outlook

-   Significant Mineral Resources have not been considered for this ORE, with some areas of open pit first requiring further drilling to convert to Indicated categorisation. Further Reserve conversion is targeted by ongoing resource upgrade drilling and mine optimisation studies.

-   Telfer residual resources not included in this ORE³ include:

§ West Dome Open Pit - 244Mt at 0.45g/t Au & 0.04% Cu for 3.5Moz Au & 103kt:

§  Indicated: 24.5Mt at 0.42g/t Au & 0.05% Cu for 0.4Moz Au & 13kt Cu

§  Inferred: 219Mt at 0.45g/t Au & 0.04% Cu for 3.2Moz Au & 89kt Cu

§ Underground - 53.9Mt at 1.53g/t Au & 0.37% Cu for 2.6Moz Au & 201kt Cu across MDU, WDU and VSC:

§  Indicated 40.2Mt at 1.43g/t Au & 0.36% Cu for 1.8Moz Au & 144kt Cu

§  Inferred 13.7Mt at 1.82g/t Au & 0.42% Cu for 0.8Moz Au & 57kt Cu

§  WDU and VSC not included in ORE, with both subject to ongoing studies

-   Upside potential from Inferred Resources within the ORE mining shapes but treated as waste includes:

§ Open pit - Potential to convert 42% more gold from Inferred Resources that is treated as waste within the ORE pit shell.

§ Inferred to Indicated open pit conversion continues to occur at excellent rates (>85%), with further conversion having the potential to materially reduce the LOM strip ratio of the ORE shell

§ Underground - Potential to convert 8% more gold from Inferred Resources contained within underground mining shapes but treated as unmineralised waste dilution in the underground ORE, which has the potential to improve mined grades

-   Future resource and reserve growth targeted by maintaining current drilling rates into FY27 and continued study work at WDU and VSC.

§ Economic factors:

-   Telfer ORE includes updated cost and revenue assumptions with assumed medium-term metal prices of A$4,000/oz for gold and A$6.00/lb for copper (for Telfer ORE), and long-term prices of A$2,500/oz gold and A$4.60/lb copper (for Havieron ORE, unchanged). This compares to respective spot prices of ~A$5,930/oz gold and ~A$8.70/lb copper⁴.

Financial Close of Corporate Debt Facility B

Greatland is pleased to advise that it has achieved financial close on Facility B of its $500m corporate debt facility⁵. Facility B is a $225m (undrawn) revolving credit facility with 7-year tenor for working capital and general corporate purposes, including Havieron development.

Notes:

(1)   Refer to Greatland's 1 December 2025 announcement titled 'Havieron Project Feasibility Study'.

(2)   Refer to Greatland's 30 March 2026 announcement titled 'December 2025 Group Mineral Resource Statement.' Greatland also makes updates to the Telfer West Dome Open Pit Mineral Resource as at 31 March 2026, as detailed further in this announcement, subsequent to the Group Mineral Resource reported on 30 March 2026.

(3)   Telfer residual resources represent the difference between the disclosed Telfer Mineral Resource Estimate and the Telfer Ore Reserve Estimate, being the Mineral Resource not converted to Ore Reserve at the 31 March 2026 statement date.

(4)   Spot pricing data sourced from S&P Capital IQ as at 27 June 2026.

(5)   Refer to Greatland's 1 June 2026 announcement titled 'Execution of Corporate Debt Facilities and Havieron Approval'.

Greatland Managing Director, Shaun Day, commented:

"Telfer and Havieron's combined Reserve of 5.0Moz gold and 196kt copper is an outstanding achievement and an important step towards a multi-decade mine life for the world class Telfer-Havieron gold-copper complex.

This substantial uplift in reserves at Telfer only reflects drilling from just our first 12 months of ownership, with ongoing high cadence drilling planned to support future resource and reserve upgrades. We see strong potential to bring on additional high-grade underground mining areas and yield significant growth in future reserve updates via ongoing studies at the West Dome Underground and Main Dome Underground VSC.

At the West Dome Open Pit, substantial Inferred Resources are contained within the ORE pit shell but treated as waste, presenting an important upside opportunity. If converted into Reserve this material could meaningfully lower our strip ratios, noting we have achieved exceptional recent rates of conversion from Inferred to Indicated in the West Dome Open Pit.

Our drilling success to date clearly demonstrates the scale of Telfer's mineral system which underpins the opportunity to continue fully utilising our low cost and large-scale processing infrastructure well into the future. With substantial baseload reserves now in place at Telfer, a key focus for us is advancing higher-grade opportunities at Telfer in parallel with the development of Havieron. Our strategy is to increase the contribution of high-grade underground ore as a proportion of our processing feed over time."

This announcement is approved for release by Shaun Day, Greatland's Managing Director.

Contact

For further information, please contact:

Greatland Resources Limited

Shaun Day, Managing Director  |  Andrew Bowler, Head of Investor Relations

[email protected]

Nominated Advisor

SPARK Advisory Partners

Andrew Emmott / James Keeshan / Neil Baldwin  |  +44 203 368 3550

Corporate Brokers

Canaccord Genuity  |  James Asensio / George Grainger  |  +44 207 523 8000

RBC Capital Markets  |  James Agnew / Jamil Miah  |  Scott Redwood  |  +44 207 029 0528

Media Relations

Australia - Fivemark Partners  |  Michael Vaughan  |  +61 422 602 720

About Greatland

Greatland is a gold and copper mining company listed on the Australian Securities Exchange and London Stock Exchange's AIM Market (AIM:GGP, ASX:GGP), and operates its business from Western Australia.

The Greatland portfolio includes the 100% owned Telfer mine, the adjacent 100% owned brownfield world-class Havieron gold-copper development project, and a significant exploration portfolio within the surrounding region. The combination of Telfer and Havieron provides for a substantial and long-life gold-copper operation in the Paterson Province in the East Pilbara region of Western Australia.

Group Ore Reserve summary

The March 2026 Group Ore Reserve (Table 1) is based on the 31 December 2025 Mineral Resource Estimate (see ASX/AIM Announcements dated 30 March 2026), including a subsequent update to West Dome Open Pit Mineral Resource classification from ongoing drilling as at 31 March 2026, as detailed further in this announcement, and comprises five key areas (Figure 3 to Figure 6), being:

§ Telfer West Dome Open Pit (WDO) (active surface mining operation)

§ Telfer Main Dome Underground (MDU) (active underground mining operation)

§ Telfer Dump Leach (active)

§ Telfer Surface Stockpiles (active and historical)

§ Havieron Underground Project (unchanged - as per 1 December 2025 announcement)

Table 1: March 2026 Group Ore Reserve Statement as at 31 March 2026

Notes:

§ Grades are reported to two decimal places to reflect appropriate precision in the estimate, and this may cause apparent discrepancies in totals.

§ The ORE is reported for contained Measured and Indicated Mineral Resource material delivered to the Run-of-Mine (ROM) pad, stockpiles and dump leach pads, and excludes concentrate already produced and gold in circuit in the Telfer process plant.

§ Cut-offs for the Havieron ORE are applied based on a variable break-even calculation using net smelter return (NSR), long-term metal prices of A$2,500/oz Au and A$4.60/lb Cu, average metallurgical recoveries of 86.6% gold and 84.4% copper, reported within mining shapes based on a sub-level open stoping mining method with cemented paste fill and above a break-even cut-off grade of A$82/t NSR processed, as stated in the 01 December 2025 Havieron Announcement.

§ Cut-offs for the Telfer ORE are applied based on a variable break-even calculation using net smelter return (NSR), medium-term metal prices of A$4,000/oz Au and A$6.00/lb Cu and current site cost and operating conditions specific to each ore source. Open pit and underground ore are co-processed through the current Telfer processing plant:

§West Dome Open Pit: Conventional truck and shovel open pit, ranging $16.7-25.3/t processed, 78-81% gold and 65-78% copper recoveries.

§ Main Dome Underground: Longhole open stoping mining method with stope widths ranging from narrow reef to bulk stockwork stopes. Cut-offs range from $51/t for bulk stoping variable cost to $158/t processed fully costed for narrow reef stoping. Metallurgical recoveries average 90% gold and 94% copper.

§Dump Leach: Conventional dump leach, $4.9/t average leach cost with 30-50% gold recovery. No copper is recovered from dump leach material.

§ Stockpiles:  Conventional truck and loader rehandle, ranging $16.4-17.4/t processed, 78-86% gold and 50-65% copper recoveries.

Telfer Mine Ore Reserve Estimate material information

A Material Information Summary for the Telfer Ore Reserve Estimate is provided in accordance with JORC Code 2012 Edition requirements. The Assessment and Reporting Criteria in accordance with the JORC Code 2012 are presented in Appendix 1.

Material changes to the Telfer ORE are summarised below. For details on the Havieron ORE component refer to the 1 December 2025 Feasibility Study announcement titled 'Havieron Project Feasibility Study'.

Location and background

The Telfer gold-copper mine and nearby Havieron Project (Telfer-Havieron) is 100% owned by Greatland and is located in the Paterson Province of the East Pilbara region in Western Australia, approximately 485 km by road south-east of Port Hedland (Figure 1). Telfer first produced gold in 1977 and has produced more than 15Moz of gold to date. The Havieron Project is approximately 45km east of the Telfer Mine.

Figure 1: Paterson Province regional map

Telfer is a fly-in fly-out mine with both open pit and underground mining operations, an established workforce and significant infrastructure. Gold and copper are produced by a large processing facility comprising two 10Mtpa capacity trains, totalling 20Mtpa in nominal capacity, that produces gold doré and a copper-gold concentrate.

Ore from Telfer is currently sourced from the West Dome Open Pit and the Main Dome Underground mines. Processing operations treat material from underground and open pit mining and existing stockpiles and includes dump leach.

The Telfer Mineral Resources are located across mining leases M45/6, M45/7, M45/8 and M45/33. The Havieron Project is entirely contained within the Mining Lease M45/1287. This tenement wholly replaced 12 sub-blocks of E45/4701 and was granted on 10 September 2020.

Infrastructure and surface overview

All material infrastructure required to deliver the Telfer ORE are currently in place as part of active operations. Figure 2 shows the existing major Telfer Infrastructure.

Figure 2: Telfer Site Major Infrastructure

Material infrastructure to the Telfer ORE includes:

§ Process plant - 20Mtpa processing capacity through two parallel trains

§ Water - existing potable and raw water infrastructure to support a 20Mtpa operation

§ Power - Primary gas-powered power station with 135MW capacity fed via pipeline from Port Hedland, and back-up secondary diesel power station with 11MW capacity

§ Office and workshops - fully equipped and operating offices for personnel and workshops to maintain the open pit and underground fleet

§ Transport access - Telfer Mine Road connected to Port Headland via highway, and operational port facilities for concentrate shipment

§ Airstrip - Sealed airstrip capable of landing jet airplanes

§ Camp - 1,700 room camp and associated facilities to accommodate fly-in-fly-out workforce

§ Tailings - Six inactive facilities, one being remediated (TSF7) and one operational (TSF8) with sufficient final design capacity to store the current Ore Reserves tailings.

Telfer ORE Estimation and Classification

The Telfer ORE is based on the latest December 2025 Group Mineral Resource Estimate, as detailed in the Company's announcement dated 30 March 2025 titled 'December 2025 Group Mineral Resource Statement', including a subsequent update to West Dome Open Pit Mineral Resource classification from ongoing drilling as at 31 March 2026, as detailed further in this announcement. Ore Reserves are a subset of Measured and Indicated Mineral Resources only. Only a small proportion of Measured Mineral Resource exist in ROM stockpiles, which were converted to Proved Ore Reserves. Probable Ore Reserves were only derived from Indicated Mineral Resources.

Inferred Mineral Resources were treated as internal waste dilution at zero grade with inferred metal content removed for the purposes of reporting Ore Reserves.

The Telfer ORE was generated mostly from extending current operations at the Telfer mine (Figure 3) and are considered to be at a pre-feasibility study level of accuracy or better. Appropriate mining, metallurgical and economic modifying factors were applied to each specific mine area and material type and are based on current operating practices.

Current operations consist of conventional truck and shovel open pit and underground longhole open stoping mining methods and are considered the most appropriate method for this ORE. Optimisation and design software used was GEOVIA Whittle and Vulcan for open pit and Deswik Suite for underground. Short to medium-term metal price forecasts of A$4,000/oz gold and A$6.0/lb copper were used to calculate a NSR value for each mineralised block, which was then considered for inclusion in the ORE based on break-even cut-off grades relevant to each resource and mining location. Only gold and copper contribute to the NSR calculation to produce gold doré or copper concentrate containing gold, except for dump leach which only produces gold doré. No material deleterious elements or penalties apply to the Telfer saleable products.

Mining, processing and additional overhead costs are based on currently contracted and budgeted operating costs. Mill recoveries for all ore types are based upon operating experience, supported by additional metallurgical test work for extensions to current areas. Ore Reserves consider environmental, tenement, government and infrastructure approvals along with transportation requirements to market. Telfer is an operating site and has all the required major infrastructure such as power generation, processing, waste rock and tailings disposal, process and potable water, camp, airport, access roads and port handling facilities.

Stockpiles consist of ROM stocks and low-grade stocks both mined by Greatland and accumulated by previous owners.

Figure 3: Telfer March 2026 Ore Reserve mining areas (includes schematic of WDU and VSC resource areas)

Reporting Date and Depletion

The Telfer ORE is reported as at 31 March 2026. Material depleted prior to this date was removed from the estimate. Reserves are reported on a metal contained basis as delivered to the ROM, stockpiles or dump leach pads, and excludes metal already in circuit or concentrate already produced through the process plant.

Mining - West Dome Open Pit (WDO)

The WDO Ore Reserve is based on a Whittle optimisation shell, modified through detailed pit designs to the optimisation shells to ensure compliance with practical mining parameters (Figure 4, Figure 5). The WDO Ore Reserve is only derived from the Indicated component of the Mineral Resource Model. No Inferred or unclassified material is included within the open pit Ore Reserve. Where Inferred or unclassified material is present this material is classified as waste and does not contribute to the ORE.

Geotechnical parameters are a combination of observed performance in the existing pit and domain specific estimates. Various geotechnical reports and retrospective reconciliations were considered in the design parameters. No specific ground support requirements are needed outside of suitable pit slope design criteria based on specific geotechnical domains.

Minimum mining widths have been accounted for in the designs as per the current operating fleet, utilising CAT793 trucking parameters and CAT6060 digger parameters:

§ Bench height of 12m mined in three 4m flitches

§ Dual lane road width of 35m and single lane ramp width of 20m (typically only final bench)

§ Maximum road grade of 10%

§ Minimum mining width of 50m for single excavator and 80m for two excavators

No further mine dilution is applied to the resource model as the smallest sub-cell in the block model is larger than the minimum mining unit of the current mining equipment in operation. An ore loss of 6% was applied to in situ tonnes to account for losses during mining.

Mining sequence is included in the mine scheduling process for determining the economic evaluation and takes into account available operating time and mining equipment size and performance.

Figure 4: WDO Pit December 2025 Mineral Resource (plan view) with March 2026 ORE pit design outline

Figure 5: WDO Pit December 2025 Mineral Resource (section A-B) with March 2026 ORE pit design outline and Mineral Resource Estimate (MRE) optimisation shell outline

Mining - Main Dome Underground (MDU)

The Main Dome Underground portion of the Telfer ORE (Figure 6) has been defined across the active A Reefs, M Reefs, Eastern Stockwork Corridor (ESC), Kylo, Southwest, Western Flanks and Rey orebodies, all within close proximity to the existing infrastructure and requiring limited capital development to access. WDU and VSC are not yet included in Ore Reserve estimates and are part of ongoing drilling and studies.

MDU mining methods use conventional longhole open stoping with a combination of rib or sill pillars to extract reef and stockwork style mineralisation. The Rey deposit utilised cemented paste fill to maximise extraction until early 2026 and the paste plant and distribution network is maintained and available to future opportunities such as the WDU resource.

Underground access is provided via a single decline from surface, branching into local declines for individual deposits. A vertical shaft is also operational. This provides flexibility and spare capacity in both truck haulage and vertical hoisting capability. The hoist is fed via an underground crusher and has an installed capacity of almost 6Mtpa for the historical sub-level cave (SLC). Current underground mining rate is ~1.0-1.5Mtpa since the SLC stopped, providing substantial upside capacity to future underground mining opportunities.

Access to production stopes is generally off the main decline or via a local decline onto level access drives, followed by longitudinal ore drives along the reef mineralisation. Stoping is mostly longitudinal retreat, with some wider areas using transverse mining (Rey).

Figure 6: Main Dome Underground Ore Reserve (March 2026)

Initial stope optimisation is performed using Deswik.SO on a net smelter return (NSR) value in the Mineral Resource Model based on expected metallurgical recoveries and selected Ore Reserve gold and copper prices. For Life of Mine designs all resource categories are considered for the stope optimisations, but for the Ore Reserve designs only Measured and Indicated categories are considered and metal from Inferred and unclassified material is zeroed and treated as planned dilution/waste. Stopes are optimised above a marginal break-even cut-off grade specific to each mining area, ranging between A$51-A$158/t depending on location (mainly decline trucking versus shaft hoisting), stope size and geometry and local mining conditions.

Mine designs are based on local geotechnical conditions and large conventional underground mining equipment such as 21t loaders and 63t trucks, resulting in typical level spacings averaging 20-25m, with minimum stoping widths of 2m and stope lengths of 15-30m. Planned dilution is included using SO's standard ELOS option for hanging wall and footwall overbreak based on local geotechnical modelling and historical mining experience, while ensuring stope footwalls are steeper than the natural rill angle of blasted rock for shallower dipping deposits. 

Initial stope shapes are then manually refined to ensure mining operability and practical mining considerations are incorporated. Unplanned dilution and mining losses are applied specific to each mining area, ranging between 10-30% dilution and 85-90% recovery. Financial analysis is performed on the final designs and diluted and recovered inventory to ensure individual mining areas and stoping levels provide sufficient free cashflow to offset capital development and infrastructure required to access and extract the mineralisation from each area. Global analysis is also performed to ensure entire mining areas are economically viable.

All major capital infrastructure is in place for Telfer Underground, consisting of multiple primary ventilation shafts, refrigeration capacity for warmer summer months, primary pumping and dewatering, primary power distribution, underground crusher and shaft hoisting and underground workshop and maintenance facilities. New areas are accessed primarily via local capital development only and linking into the existing primary systems already in place.

Stockpiles

Substantial surface stockpiles continue to be maintained at Telfer, providing flexibility, resilience and optionality to continue fully utilising Telfer's 20Mtpa processing capacity. The March 2026 Telfer ORE includes 22.5Mt at 0.36g/t Au and 0.05% Cu for 0.3Moz gold and 11kt copper in stockpile reserves.

Bulk processing trials of the historical components of these stockpiles were completed during H1 CY2026 and confirmed processing assumptions and viability for inclusion in this ORE.

Processing

The Telfer processing plant consists of two largely independent trains each capable of processing approximately 10Mtpa, with total nominal annual processing capacity of approximately 20Mtpa, which is currently the third largest gold-copper processing plant capacity in Australia.

Figure 7: Telfer processing flowsheet

The processing flowsheet for Telfer is illustrated in Figure 7. The processing plant includes gyratory crushing, semi-autogenous grinding (SAG) and ball mill (SAB) grinding, sequential flotation of copper and pyrite, pyrite concentrate regrind followed by cyanide leaching and copper concentrate filtration.

The two trains are configured the same through the crushing, milling, copper and pyrite rougher flotation (except that Train 1 has two additional pyrite rougher cells) and copper cleaning stages. The two trains combine into a single stream at the tailings thickener, copper concentrate filtration, and downstream from the pyrite roughers (pyrite cleaners/pyrite regrind/pyrite leaching).

Telfer produces a gold doré and a copper-gold concentrate product.

Telfer copper-gold concentrate is transported by road to Port Hedland approximately 450km away and is sold under concentrate sales agreements that the Group has either entered into or will enter into.

Dump Leach

Dump leach is used to treat low grade, mostly oxidised material from the open pit mining operations. Suitable low-grade ore is dumped onto the leach pads during mining (current active pad is Dump Leach 237). Reagent irrigation produces a leachate from which the gold is recovered and sold as doré. All required infrastructure is in place to continue to operate the dump leach well beyond the current Ore Reserve requirements.

Environmental and Permitting

The Telfer-Havieron Gold Mining Project has received Federal and State primary environmental approvals as follows:

§ Approval of the Havieron Project Controlled Action EPBC 2021/9085 granted on 24 April 2026 under sections 130(1) and 133(1) of the Commonwealth Environmental Protection and Biodiversity Conservation Act 1999.

§ Ministerial Statement 1273 granted on 25 May 2026 by the WA Minister for the Environment under Part IV of the Environmental Protection Act 1986.

In addition to these, Telfer-Havieron is operated under further environmental approvals under WA legislation. Only minor adjustments are required to match the WDO Open Pit final pit boundary, which is located within previously disturbed areas. Ongoing compliance with environmental and other governmental approvals relevant to the successful execution of the ORE is not considered a material risk.

Native title and Cultural heritage

Greatland and Jamukurnu-Yapalikurnu Aboriginal Corporation (JYAC), the Registered Native Title Body Corporate of the Martu People, are parties to an Indigenous Land Use Agreement (Telfer-Havieron ILUA). The Telfer-Havieron ILUA was registered as an Indigenous Land Use Agreement (body corporate agreement) in February 2016 in accordance with the Native Title Act 1993 (Cth).

The Telfer-Havieron ILUA applies to a project area comprising a 60km radius centred on the Telfer mine processing plant, to the extent such land falls within the Martu determination area, covering both the Telfer and Havieron ORE areas. Greatland shares a strong positive working relationship with JYAC, and do not foresee any native title or cultural heritage risks impacting the successful execution of the ORE.

Closure and Rehabilitation

The majority of the Telfer site is still in active operations. An approved Mine Closure Plan is in place for Telfer, and includes the long-term use of Telfer infrastructure for the Havieron Project. Progressive rehabilitation has occurred on parts of landforms that are no longer in use, and opportunities for ongoing progressive rehabilitation is evaluated on an ongoing basis. The Mine Closure Plan will continue to be updated in accordance with regulatory requirements and is not considered a risk to the successful execution of the ORE.

Economic evaluation and Sensitivity

The accuracy of the estimates within this Ore Reserve is mostly determined by the order of accuracy associated with the Mineral Resource model, the metallurgical input, geotechnical design parameters, mine equipment, metal prices and the cost factors used. The Telfer ORE is based on a proven history of operating practices, ore metal grade, operating cost, geotechnical stability, and metallurgical recoveries. Estimated operating and sustaining capital costs developed for the remaining mine life have been calculated to a pre-feasibility level of accuracy or better and are supported by the continuation of current operating practices.

Gold is the primary value contributor. As such, the Ore Reserves are most sensitive to assumptions impacting gold value, such as gold price, gold grade and gold metallurgical recoveries.

The Competent Person is not aware of any modifying factor that may materially impact this Ore Reserve Statement and the Ore Reserve is supported by a positive cash flow analysis. The Competent Person views the Telfer ORE to be a reasonable and appropriate global estimate.

Comparison to previous Greatland Group ORE

Figure 8 and Figure 9 show a comparison of the Group March 2026 ORE to the Group December 2024 ORE modal changes for tonnes and ounces, inclusive of 15-months of active depletion by mining and processing. Growth is primarily as a result of Greatland's successful ongoing drilling campaign and ongoing mine optimisation and technical and economic studies to convert increased resources to reserves.

Figure 8: Greatland Group Ore Reserve Modal Change - ore tonnes (Mt)

Figure 9: Greatland Group Ore Reserve Modal Change - gold ounces (Moz)

Telfer Mineral Resource Statement - West Dome Open Pit update

Greatland is pleased to announce an update to the Telfer West Dome Open Pit Mineral Resource Estimate (MRE) as at 31 March 2026. Subsequent to the Group MRE reported on 30 March 2026 (based on drilling up to 31 December 2025) conversion drilling has continued with new drilling completed between 1 January and 31 March 2026 informing an update for the West Dome Open Pit MRE. This resulted in approximately 15Mt of Inferred material successfully being converted into the higher confidence Indicated classification with no material change in total resource tonnes, metal or grade.

This classification change, along with depletion during the March 2026 Quarter, has resulted in a Total MRE for the West Dome Open Pit of 336Mt at 0.45g/t Au and 0.04% Cu for 4.9Moz of gold and 148kt of copper. There has been no material change to the remainder of Greatland Mineral Resources as announced on 30 March 2026 in our Group Mineral Resource Statement.

Table 2: March 2026 Telfer Mineral Resource Statement

Notes:

§ Mineral Resources are reported as at 31 December 2025, with the exception of the West Dome Open pit that is Reported as at 31 March 2026.

§ Grades are reported to two decimal places to reflect appropriate precision in the estimate, and this may cause apparent discrepancies in totals.

§ Cut-offs for the Telfer MRE are applied based on a NSR using metal prices of A$4,200/oz Au and A$6.50/lb and current site cost and revenue assumptions.

§ Between 1 January 2026 and 31 March 2026, a total of 4.7Mt at 0.61g/t Au and 0.12% Cu for 93koz gold and 3.9kt copper were depleted from Resources through active mining or processing of stockpiles:

§ 3.6Mt at 0.49g/t Au and 0.07% Cu for 57koz gold and 1.8kt copper in the West Dome Open pit.

§ 0.8Mt at 0.59g/t and 0.06% Cu for 16koz gold and 0.6kt of copper have been depleted from stockpiles.

§ 315kt at 2.08g/t Au and 0.80% Cu for 18.8koz gold and 2.5kt copper in the Main Dome Underground.

Forward Looking Statements

This document includes forward looking statements and forward looking information within the meaning of securities laws of applicable jurisdictions. Forward looking statements can generally be identified by the use of words such as "may", "will", "expect", "intend", "plan", "estimate", "anticipate", "believe", "continue", "objectives", "targets", "outlook" and "guidance", or other similar words and may include, without limitation, statements regarding estimated reserves and resources, certain plans, strategies, aspirations and objectives of management, anticipated production, study or construction dates, expected costs, cash flow or production outputs and anticipated productive lives of projects and mines.

These forward looking statements involve known and unknown risks, uncertainties and other factors that may cause actual results, performance and achievements or industry results to differ materially from any future results, performance or achievements, or industry results, expressed or implied by these forward-looking statements. Relevant factors may include, but are not limited to, changes in commodity prices, foreign exchange fluctuations and general economic conditions, increased costs and demand for production inputs, the speculative nature of exploration and project development, including the risks of obtaining necessary licences and permits and diminishing quantities or grades of reserves, political and social risks, changes to the regulatory framework within which Greatland operates or may in the future operate, environmental conditions including extreme weather conditions, recruitment and retention of personnel, industrial relations issues and litigation.

Forward looking statements are based on assumptions as to the financial, market, regulatory and other relevant environments that will exist and affect Greatland's business and operations in the future. Greatland does not give any assurance that the assumptions will prove to be correct. There may be other factors that could cause actual results or events not to be as anticipated, and many events are beyond the reasonable control of Greatland. Forward looking statements in this document speak only at the data of issue. Greatland does not undertake any obligation to update or revise any of the forward looking statements or to advise of any change in assumptions on which any such statement is based.

Competent Person Statements

The information in this announcement pertaining to estimation and reporting of the Greatland March 2026 Group Ore Reserve Estimate is based on, and fairly reflects, information and supporting documentation compiled by Otto Richter, Group Mining Engineer. Mr Richter is a full-time employee of the Greatland Group and has a financial interest in the Company. Mr Richter is a Fellow of the Australasian Institute of Mining and Metallurgy (FAusIMM #301723) and has over 25 years relevant industry experience. Mr Richter has sufficient experience that is relevant to the style of mineralisation and type of deposits under consideration and to the activity currently being undertaken to qualify as a Competent Person as defined in the 2012 Edition of the 'Australasian Code for Reporting Exploration Results, Mineral Resources and Ore Reserves' and under the AIM Rules - Note for Mining and Oil & Gas Companies, which outline standards of disclosure for mineral projects. Mr Richter consents to the inclusion in this announcement of the matters based on that information and supporting documentation in the form and context in which it appears.

The information in this announcement pertaining to estimation and reporting of the Telfer West Dome Open Pit Mineral Resource estimates is based on, and fairly reflects, information and supporting documentation compiled under the supervision of Michael Thomson, Principal Geologist at Greatland. Mr Thomson is a full-time employee of the Greatland Group and has a financial interest in the Company. Mr Thomson is a member of the Australian Institute of Geology (AIG) and has over 20 years' relevant industry experience. Mr Thomson has sufficient experience that is relevant to the style of mineralisation and type of deposits under consideration and to the activity currently being undertaken to qualify as a Competent Person as defined in the 2012 Edition of the 'Australasian Code for Reporting Exploration Results, Mineral Resources and Ore Reserves' and under the AIM Rules - Note for Mining and Oil & Gas Companies, which outline standards of disclosure for mineral projects. Mr Thomson consents to the inclusion in this announcement of the matters based on that information and supporting documentation in the form and context in which it appears.

Appendix 1: JORC Tables

JORC Code, 2012 Edition - Table 1 Section 1: Sampling Techniques and Data

JORC Code, 2012 Edition - Table 1 Section 2: Reporting of Exploration Results

JORC Code, 2012 Edition - Table 1 Section 3: Estimation and Reporting of Mineral Resources

JORC Code, 2012 Edition - Table 1 Section 4:
Estimating and Reporting of Ore Reserves (Telfer)