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Study Outcomes

Area

Measure

Unit

Phase 14A^2,3

LOM⁹

Production

Ore milled / milling rate (max)

Mtpa

15.5

15.5

Ore milled

Mt

-

310

LOM

Years

5^[10]

22

Ore mined

Mt

20.5

236

Average gold grade

g/t

2.4

2.3

Gold produced

Moz

1.0

19

Capital

Production stripping (capitalised)

US$m (real)

111

Sustaining capital

US$m (real)

69

Total capital

US$m (real)

179

Economic assumptions

Gold price

US$/oz

1,500

Financials¹¹

NPV⁸

US$m (real)

284

IRR

% (real)

37

Payback period⁴

Years

2.6

Material Class

Tonnage (Mt)

Au Grade (g/t)

High Grade (HG)

4.5

4.5

Medium Grade (MG)

8.5

2.2

Low Grade (LG)

7.5

1.3

Waste

13.5

Total

34

Stripping Ratio (Waste: Ore)

0.66

Activity

$m^2,7

Study and trial costs

22

Mining and ancillary fleet
(Excluding contractor ground support equipment)

46

Production stripping cost (capitalised)

111

Total

179

Year

Sources

Total Material Movement (Mt)^[16]

Waste (Mt)

Tonnes to Stockpile
(Mt)

Ex-Pit
Tonnes
Fed (Mt)

Stockpile
Tonnes
Fed (Mt)

Plant
Feed
(Mt)¹⁷

Average
Gold Grade (g/t)

FY22-24

Lienetz, medium/low grade stockpiles and pre-strip

200 - 220

100 - 120

15 - 25

25 - 35

10 - 20

40 - 50

2.4 - 2.6

FY25-27

Lienetz, Kapit, medium/low grade stockpiles and pre-strip

210 - 230

90 - 110

25 - 35

25 - 35

10 - 20

40 - 50

2.8 - 3.0

FY28-30

Lienetz, Kapit, low grade stockpiles and pre-strip

160 - 180

80 - 100

5 - 15

10 - 20

30 - 40

40 - 50

2.4 - 3.0

FY31-33

Lienetz, Kapit, Minifie and low grade stockpiles

140 - 160

40 - 60

20 - 30

25 - 35

10 - 20

40 - 50

2.6 - 3.0

FY34-36

Lienetz, Kapit, Minifie and low grade stockpiles

130 - 150

50 - 70

10 - 20

25 - 35

10 - 20

40 - 50

2.0 - 2.3

FY37-39

Minifie and low grade stockpiles

50 - 70

0 - 10

0 - 10

0 - 10

40 - 50

40 - 50

1.3 - 1.5

FY40-42

Minifie and low grade stockpiles

30 - 50

0 - 10

0 - 10

0 - 10

25 - 35

25 - 35

1.2 - 1.3

FY43+

Remaining Reserves subject to ongoing study

Scenario

Assumption

IRR

Gold price ($/oz)

1,200

22%

1,800

51%

FY23

FY24

FY25

FY26

FY27

FY28

FY29

Total

Stage 1 - Cut-Off Wall ($m)

30

74

194

52

-

-

-

350

Stage 2 - Seepage Control Berm ($m)

-

-

-

35

95

70

19

219

Total ($m)

30

74

194

87

95

70

19

569

Mineral Resource

Gold

Mt

g/t

Moz

Measured Mineral Resource

63

2.0

4.0

Indicated Mineral Resource

530

2.3

39

Total Measured and Indicated

590

2.2

43

Mineral Resource

Gold

Mt

g/t

Moz

Inferred Mineral Resource

67

2.3

4.9

Ore Reserve

Gold

Mt

g/t

Moz

Proved Ore Reserve

63

2.0

4.0

Probable Ore Reserve

250

2.4

19

Total Ore Reserve

310

2.3

23

Criteria

Commentary

Sampling techniques

Lihir is located in an active geothermal area and procedures have been developed to ensure that all drilling activities are conducted in a safe manner which is appropriate for when zones of high pressure steam are intersected. Data used for the resource estimation is obtained by two main drilling methods - diamond coring and reverse circulation (RC) drilling. All available diamond drill holes are sampled by cutting the core in half with a diamond saw with sample intervals being either 1m or 2m in length. Half the cut core is placed in a calico bag with a sample number and sent to the laboratory for assaying. All RC drilling was sampled at 1m intervals collected via a cyclone and split with a riffle splitter. The riffle split sample size of 4-5kg is placed in a calico bag with a sample number and sent to the laboratory for assaying.

Drilling techniques

Drilling is the primary source of data for Mineral Resource estimation at Lihir. Data is obtained from two main drilling methods-diamond coring and RC drilling. The majority of drilling for the resource estimation is diamond drill core (93%), comprising PQ (84.8 mm core diameter), HQ (63.5 mm core diameter) and NQ (47.6 mm core diameter). Very little core orientation is performed on site as the structurally complex and geothermal conditions make it very difficult to obtain accurate orientations. Minor (~7%) of resource drilling is RC (5 1/4'" diameter) completed prior to 2002 used both vertical and angled holes. Since 2002 all resource drilling has been comprised of diamond core. Stockpile drilling is campaigned using an RC rig with a 4" bit. Hole lengths are routinely 36m.

Drill sample recovery

Core recovery is recorded and stored in an acQuire software database. There are only minor zones of core loss or poor core recovery. Core recovery is generally excellent with average core recoveries around 99%. There is no identified relationship between core loss and grade and the style of mineralisation suggests this is unlikely. There are no records of RC sample recovery.

Logging

All diamond drill holes are geologically logged. Due to the nature of the intense alteration core is qualitatively logged for lithology and alteration and quantitatively logged for structure and geotechnical parameters. All core is logged and photographed after marking up metre intervals and prior to cutting and sampling. Logging data are entered into the acQuire database via a laptop computer or historically via manual data entry.

Sub-sampling techniques and sample preparation

The sampling technique used is considered appropriate for the assessment of Lihir mineralisation. At the completion of drill core logging, the geologist defines which intervals of a drill hole are to be cut for analysis. All recent drilling is analysed on 2m intervals on the metre mark. PQ and HQ sized drill core is sampled by cutting the core in half with a diamond blade saw when intact and competent. The left hand half is placed in a calico bag marked with the appropriate sample number and sent to the assay laboratory for analysis. Where the core is too soft to be cut with a diamond saw, a knife is used to cut the core in the core tray. Where the core is too broken or brittle to be cut by the saw, the fragments are manually sampled. NQ sized core is not cut in half as the entire section is sampled so that sample support is maintained. The standard sampling interval is 2m but has varied over time from 1m to 2m. The remaining half core is stored in the original trays on pallets at the core processing facility.

Lihir has a sample preparation facility at the mine and up to January 2015 there are records for crusher duplicates. Drill core was crushed and RC and blast hole samples were dried and loaded into the pulverisers without laboratory splitting. After 2015 there was a reduction in core sampling and all samples were transferred directly to a bank of 6 * LM5 pulverisers without crushing or splitting. There are two standby jaw crushers with a small single deck riffle splitter which are rarely used.

Sample preparation for analysis is as follows: Samples are crushed if required to 10mm maximum diameter and split to a nominal weight of 2.5 - 3kg using a riffle splitter. Split samples are dried in an oven at 105°C until dry. Each sample is pulverised using a Labtechnics LM5 pulverizing mill to specified grind parameters of 95% passing 106µm. A 200g sub-sample is collected for analysis and submitted to the assay laboratory. Pulp replicates (not duplicates) are routinely undertaken. Crushed and pulp duplicates are collected at the Orange laboratory.

The sample preparation and size is considered appropriate for assessment of bulk tonnage mineral deposits of this type.

Quality of assay data and laboratory tests

The Lihir onsite laboratory has been the primary laboratory used for assaying, with some more recent assaying completed at the Newcrest Services laboratory (Orange, NSW).

Samples are routinely assayed for gold and sulphur. Gold analysis is by fire assay with 25g charge and Atomic Absorption Spectroscopy (AAS) finish and detection limit of 0.01ppm (g/t), which is considered complete. Sulphide sulphur is by Labfit method where the sample is ignited at high temperature in a stream of oxygen. The resulting sulphur dioxide is measured by an infra-red detector using a Carbon/Sulphur analyser.

A detailed Quality Assurance/Quality Control (QAQC) program is in place for on-going assessment of sampling and analytical procedures. The process currently involves analysis of blind submissions of certified reference material (standards) to Lihir laboratory, duplicates from the LM5 pulveriser pulp, assayed during the same batch, blind resubmission of pulps to Lihir laboratory, replicate submissions of pulps to an alternative laboratory for analysis, submission of coarse blank samples (non-Lihir Island barren rock samples), checks on grind and crush size from the sample preparation steps and laboratory inspections and monthly QA/QC meetings. A monthly report is prepared detailing QA/QC performance to support the Mineral Resource estimate. There have been 30 standards used, not all of which were certified for sulphur. The first 16 standards were commercially available standards. Since 2008, there have been 14 standards used, all matrix-matched.

Data suggests that during the period between 2007 and 2012 there was a positive bias of between 5 and 20% in sulphide sulphur analysis conducted at Lihir laboratory data acquisition compared to standards reference materials. This suggests the Lihir method during this period reflects a total sulphur assay rather than the sulphide sulphur of the certified reference materials. In 2013 alternative sulphide sulphur techniques were introduced at Lihir which have improved the method accuracy. A further sulphide sulphur methodology improvement was implemented in 2016, with the installation of the Leco Infrared combustion analytical equipment.

Verification of sampling and assaying

All data and interpretative inputs to Mineral Resource estimates are checked and verified in accordance with a range of Newcrest standard operating procedures. Procedures were also in place for all historical drilling programs at Lihir. Diamond drill core samples are processed in-house using a dedicated core processing facility, sample preparation and analytical laboratory. All resource logging data is automatically uploaded to the resource database via logging notebook computers. Newcrest employs a centralised resource drill hole database team to check, verify and validate new data and to ensure the integrity of the total resource database. Day-to-day management of the resource data is undertaken by the database administrator on site using the acQuire database system. Prior to resource estimation a centralised resource team conducts further data checks to ensure data integrity prior to estimation.

Regular internal and external reviews of all geological and Mineral Resource estimation processes are conducted to check the quality and integrity of these procedures. No adjustments have been made to assay data.

Location of data points

The grid applied is a local Mine Grid that has it based on AMG Zone 56.

The original topography surface is a Light Detection and Ranging (LIDAR) surface created pre-mining. Mining activities are surveyed each month and incorporated into a topographic surface model for depletion purposes.

All completed drill hole collars are surveyed by the mine surveyors.

A variety of methods have been used to measure down hole deviation (dip and azimuth), including conventional borehole camera, electronic single shot and gyroscopic methods. The majority of the holes have been surveyed using conventional borehole camera methods.

Data spacing and distribution

Historical drilling has been nominally on 35m eastings, but noting the orebody is generally insensitive to drill orientation due to complex mineralisation events.

The Mineral Resource has been classified into Indicated and Inferred Mineral Resource after assessing the following factors: drill hole spacing (only areas drilled to 70m x70m drill density have been classified as Indicated Resource), style of mineralisation and geological continuity, data quality and associated QA/QC, grade continuity and proposed mining selectivity and scale of mining. Refer Section 3 Resource Classification for further details.

The data spacing and distribution is sufficient to establish geological and grade continuity appropriate for Mineral Resource estimation and classification and supported by historical reconciliation with actual production results.
Samples for estimation purposes have been taken, but no physical compositing of samples has occurred during the analysis process.

Orientation of data in relation to geological structure

Gold mineralisation in the Luise Caldera is hosted within volcanics, intrusives, and breccias which have undergone extensive alteration. Two major alteration episodes have been identified which have destroyed much of the original host rock lithologies, and due to this an "ore type" classification has been developed based largely upon various combinations of alteration, hardness, the degree of brecciation and/or leaching of matrix material, and the presence of late stage anhydrite veining. The deposit is generally sub-horizontal.

The nature of the mineralisation distribution is such that it is insensitive to drill orientation with a wide variety of orientations having been used. Diamond holes prior to 2002 are predominantly vertical, with angled holes used subsequently to define the Mineral Resource. RC holes completed prior to 2002 used both vertical and angled holes.

Sample security

Samples were transported from drill site to core shed and to site laboratory, all within the operational security zone of the mine. Sample dispatches are reconciled against Laboratory samples received and discrepancies reconciled by geology staff.

Audits or reviews

An independent review of assaying and QAQC in September 2012 concluded: "The historic assay bias for gold has now been rectified at Lihir, sulphur from sulphide has not been assayed correctly at Lihir laboratory during some stages of the life of operation. Assaying precision for gold is considered consistent with industry standards but lacking for sulphide sulphur. Overall the quality of the Lihir laboratory is now well controlled."

Criteria

Commentary

Mineral tenement and land tenure status

Mining and ore processing operations at Lihir are conducted pursuant to a mining development contract with the State of Papua New Guinea and the related special mining lease, and a series of granted mining leases, exploration licenses, leases for mining purposes and mining easements, and associated environmental and other approvals. The granted tenements and permits cover all infrastructure in the immediate vicinity of the mine site, including the open pit, accommodation, plant site, power station, waste-rock and tailings disposal, and bore fields. All infrastructure is in place for the continued operation of Lihir.

Current tenements granted under the PNG Mining Act comprise Special Mining Lease (SML) 6, two granted Mining Leases (MLs) and one granted Exploration Licence (EL), plus a number of miscellaneous mining purpose and easement leases. The total area under lease/licence is approximately 250 km2. The Mineral Resource lies entirely within SML 6. The registered holder for all tenure is Lihir Gold Limited, a wholly-owned subsidiary of Newcrest Mining Limited since late 2010. SML 6 expires 16 March 2035 and EL485 expired on 31 March 2020. Process for a new renewal from 1 April 2020 to 31 March 2022 was delayed by COVID-19 restrictions and will be lodged for EL485. The two MLs are current to July 2025.

Exploration done by other parties

The first systematic mineral exploration in the area was by the PNG Bureau of Mineral Resources and the Geological Survey of PNG between 1969 and 1974. In their report (which was released in 1982), it detailed the hydrothermal alteration and thermal activity on Lihir Island and suggested that it was a favourable geologic environment for epithermal gold mineralisation.

The Ladolam gold deposit was initially discovered in 1982 by joint venture between Kennecott Exploration and Niugini Mining. A feasibility study was completed by Kennecott Mining in March 1992. In the mid 1990's a joint venture was formed between Kennecott Mining and Rio Tinto. Lihir Gold Limited (LGL) was subsequently formed to hold the Mining Development Contract, the Special Mining Lease and associated tenure. Mining operations commenced at Lihir in 1997.

In 2005 Rio Tinto sold its interest in LGL, then, in late 2010, Newcrest Mining Limited acquired LGL by scheme of arrangement.

Geology

Exploration has identified several adjacent and partly overlapping mineral deposits in the Luise Caldera, which are collectively called the Ladolam Deposit. The principal component deposits are called Lienetz, Minifie, Coastal and Kapit. Gold mineralisation in the Luise Caldera is contained in a hydrothermally-altered porphyry gold system with the gold hosted in volcanic, intrusive and breccias within the caldera. Two major alteration episodes have been identified which have destroyed much of the original host rock lithologies, and due to this an "ore type" classification has been developed based largely upon various combinations of alteration, hardness, the degree of brecciation and/or leaching of matrix material, and the presence of late stage anhydrite veining. The majority of the gold is contained in sulphides.

The limits of the mineralisation have not been completely defined and the deposit remains are open at depth, along strike and to the east (currently limited by the Pacific Ocean).

Drill hole Information

No exploration has been reported in this release, therefore there is no drill hole information to report. This section is not relevant to this report on Ore Reserves and Mineral Resources.

Comments relating to drill hole information relevant to the Mineral Resource estimate can be found in Section 1 - "Sampling techniques", "Drilling techniques" and "Drill sample recovery".

Data aggregation methods

No exploration has been reported in this release, therefore there are no drill hole intercepts to report. This section is not relevant to this report on Ore Reserves and Mineral Resources.

Comments relating to data aggregation methods relevant to the Mineral Resource estimate can be found in Section 1 - "Sampling techniques", "Drilling techniques" and "Drill sample recovery".

Relationship between mineralisation widths and intercept lengths

No exploration has been reported in this release, therefore there are no relationships between mineralisation widths and intercept lengths to report. This section is not relevant to this report on Ore Reserves and Mineral Resources.

Diagrams

No exploration has been reported in this release; therefore no exploration diagrams have been produced. This section is not relevant to this report on Ore Reserves and Mineral Resources.

Balanced reporting

No exploration has been reported in this release, therefore there are no results to report. This section is not relevant to this report on Ore Reserves and Mineral Resources.

Other substantive exploration data

Previously reported drilling results have confirmed the extension of geological and grade continuity beyond the current Mineral Resource seaward constraint.

Further work

A concept study of mining beyond the current seaward constraint of the Mineral Resource is required to assess the reasonable prospects for eventual economic extraction of identified mineralisation outside the current Mineral Resource seaward constraint.

Criteria

Commentary

Database integrity

Data is stored in a SQL Server database known as acQuire. Assay and geological data are electronically loaded into acQuire and the database is replicated in Newcrest's centralized database system. Regular reviews of data quality are conducted by site and corporate teams prior to resource estimation, in addition to external reviews.

Site visits

The Competent Person for the Lihir Mineral Resource is part of the operational management team for Lihir Mine.

Geological interpretation

Gold mineralisation in the Luise Caldera is hosted within volcanics, intrusives, and breccias which have undergone extensive alteration. Two major alteration episodes have been identified; an earlier and deeper "porphyry style" event resulting in potassic alteration grading laterally into propylitic alteration, and a later and higher level epithermal event producing argillic, advanced argillic, phyllic, and lower temperature potassic alteration. This intensive alteration has destroyed much of the original host rock lithologies, and due to this an "ore type" classification has been developed based essentially upon various combinations of alteration, hardness, the degree of brecciation and/or leaching of matrix material, and the presence of late stage anhydrite veining. The ore types are roughly sub-horizontal in occurrence and form a fairly consistent vertical sequence of clay-rich rock, grading into white mica-feldspar rock, then feldspar-biotite and, at depth, into feldspar-biotite-anhydrite rock. Within and at the boundaries of the ore types, geological structure is also a major influence on the localization of higher gold grades in the orebodies.

Dimension

The maximum extent of the Mineral Resource is 3km x 1km x 350m. The deposit is generally sub-horizontal with the reporting of the Mineral Resource extent limited by a seaward constraint. An exploration target known as Kapit North East is a seaward extension outside the Mineral Resource.

Estimation and modelling techniques

The Lihir resource estimate contains estimates for gold, arsenic, silver, copper, carbonate, molybdenum and sulphide sulphur. Gold is the primary economic metal with sulphur and carbonate estimates required for autoclave feed management. Estimates of minor elements are required to assist with overall plant performance management.

The estimation for each element was undertaken using the non-linear estimation method of Localised Uniform Conditioning (LUC) and is based on an underlying 'diffusion' model, where, in general, grade tends to trend from lower to higher values and vice versa in a relatively continuous way. Raw data was composited to 12m intervals for gold and all other elements. Uniform Conditioning (UC) was used to estimate gold and sulphide sulphur within 100x100x12m panels. The UC model was converted to a LUC model into 20m x 20m x 12m blocks that define the selective mining unit (SMU). Ordinary Kriging (OK) was used for the local estimation of density into the SMU blocks. All other elements (arsenic, silver, copper, carbonate, molybdenum and calcium) were estimated into the SMU. All elements are estimated independently of each other.

In 2017 the estimation domains were updated for geologically interpreted fault blocks as well as geometallurgical domains. These were assessed and validated using contact analysis. Nine estimation domains were used for gold (used also for sulphide sulphur, carbonate, silver, arsenic, copper and molybdenum). Top cutting of extreme values for each element was done on a domain basis by examining the histogram of data such that the top 1% samples were cut so that they contained approximately 10% or less of total metal (for example this ranged from 4 to 30 g/t for gold domains).

The resource estimate is validated via visual, geostatistical and production reconciliation methods.

The December 2017 model is the basis of the Lihir December 2020 Mineral Resource.

Moisture

All tonnages are calculated and reported on a dry tonnes basis.

Cut-off parameters

Lihir open pit employs a grade based cut-off, taking into account metallurgical recovery assumptions, transport costs, refining charges and royalty charges. The site operating costs include mining cost, processing cost, relevant site general and administration costs and relevant sustaining capital costs. These costs equate to a break even cut off value of US$40/t milled used to define the ultimate pit shell and a marginal cut off value of US$35/t milled or 1.0 g/t gold used to define ore and waste material within the ultimate pit shell.

The marginal site cost is based on an end of mine life low grade stockpile reclaim strategy, reducing the site activity and long term cost base. The mining cost in the marginal site cost represents the stockpile reclaim cost.

Mining factors or assumptions

The Mineral Resource estimate is reported within a constraining notional pit shell. The Lihir deposit is extracted via a large Open Cut. Consequently, some aspects of the model construction reflect the proposed bulk mining method of open pit mining on 12 m benches with a 20m x 20m selective mining unit.

Metallurgical factors or assumptions

Gold extraction is by pressure oxidation of ore from a combination of direct feed and flotation feed sources depending on sulphur levels. The target sulphur content in slurry to the autoclave is in the range 5-10% to ensure auto-thermal operation of the autoclave. Ore blending and flotation plant operation is undertaken in a manner to maintain feed sulphur content in this range. Metallurgical test work and operating experience at site has shown that there are four main rock /alteration domain groups identified as: Argillic Clay, Advanced Argillic, Epithermal and Porphyry.

Gold recoveries recognise float recovery differences between in-situ and stockpile material, and overall neutralisation cyanidation adsorption (NCA) recovery formulae reflect oxidation intensity.

Environmental factors or assumptions

Lihir operations comprise an open pit mine, ore processing plant, and associated supporting infrastructure. Higher-grade ore is processed via pressure oxidation and carbon-in-leach cyanidation methods, with lower grade ore stockpiled for later processing. Lihir uses deep sea tailings placement (DSTP). In view of the heavy rainfall typically experienced on Niolam Island, the lack of suitable area for a tailings storage facility and the high seismicity of the region, DSTP was the preferred tailings placement method for Lihir. The plant tailings are premixed with sea water within the confines of the mining lease before being placed offshore. Baseline studies were undertaken prior to the approval by PNG environmental authorities and commencement of the DSTP. Regular monitoring is undertaken to verify the operational performance of the system and is subject to the regulatory criteria established by the PNG CEPA. Waste rock from the mine is either used for construction purposes or transported in barges for off-shore submarine disposal. Submarine disposal is carefully planned and controlled to achieve a continuous rill slope along the steeply dipping sea floor and to prevent uncontrolled slumping triggering a rise in water levels.

The Mineral Resource assumes the continued use of these waste management processes.

Bulk Density

All bulk density measurements are carried out in accordance with site standard procedures for Specific Gravity. The physical determination of bulk density is undertaken on solid pieces of core, 10cm in length. Intervals for bulk density determination are selected according to lithology or alteration / mineralisation type (to best represent certain intervals as defined by the geologist). The measurements are performed on site (as part of the logging process), by geological assistants. Measurements are generally taken at 50m intervals down hole, or more frequently if required. This is a dry air method of analysis.

Ordinary Kriging (OK) was used for the local estimation of density into the nine geometallurgical domains.

Classification

The in-situ Mineral Resource has been classified into Indicated and Inferred based on grade continuity assessments using the criteria of slope of regression (SOR) and the variogram weighted distance (WTD). For Indicated classification a guideline of SOR > 0.7 and WTD <75 meters was applied. For Inferred classification a guideline of SOR > 0.65 and WTD <160 meters was applied.

Stockpiles were classified as Measured and Indicated Mineral Resources based on the stockpile build methodology.

In-situ resource classification methodology has been tested with geostatistical evaluations and historical reconciliations, and appropriately confirms the Competent Persons view of the deposit.

Audits or reviews

The current Mineral Resource estimate has been externally reviewed by SRK in December 2017 and there were no issues or concerns with the Mineral Resource inputs, process and execution. SRK concluded that the Mineral Resource estimate was suitable for reporting in accordance with the requirements of the JORC Code (2012).

Discussion of relative accuracy/ confidence

For an Indicated Resource it is considered reasonable for the relative uncertainty to be +/- 15% in tonnage, grade and metal (exclusive of each other, i.e., each variable has to satisfy the criteria) for an annual production volume at a 90% confidence level. Geostatistical evaluations indicate that based on the annual processing throughputs from the pits this criteria is satisfied globally within the deposit. Relative uncertainties and confidence level estimates are only considered for gold as it is the primary economic contributor.

Detailed monthly mine reconciliations have been maintained since production commenced. The mine reconciliations since 2012 confirm that the in-situ tonnage, grade and metal variances are well within the Indicated Resource relative uncertainty band, globally.

Criteria

Commentary

Mineral Resource Estimate for conversion to Ore Reserves

A technical description of the Mineral Resource estimate that provided the basis for the December 2020 Lihir Ore Reserve estimate is presented in the preceding sections to this table.

The Ladolam gold deposit is located within the Louise Caldera, on the eastern side of Lihir Island, New Ireland Province, Papua New Guinea. Gold mineralisation in the Luise Caldera is hosted within volcanics, intrusives, and breccias that have undergone extensive alteration. The ore body is contained in a hydrothermally-altered porphyry gold system with the gold hosted in volcanic, intrusive and breccias within the caldera. The majority of the gold is contained in sulphides.

The Measured and Indicated Mineral Resources reported in the Mineral Resource report are inclusive of those Mineral Resources modified to produce the Ore Reserves Estimate herein.

Site Visits

The Competent Person for the Ore Reserve estimate is an employee of Newcrest Mining Limited and at the time of Phase 14A Ore Reserve preparation was the Senior Specialist - Long Term Planning. The CP was based on site from 2015 to 2020 providing long term and strategic planning support for operations and technical studies. This experience has been used to validate technical and operating assumptions used in the preparation of this Ore Reserve estimate.

Study Status

Production at Lihir commenced in 1996 and it is now a mature and stable operation with well-established mining and processing performance.

Cut-off Parameters

Lihir open pit employs a grade based cut-off, taking into account gold price, metallurgical recovery assumptions and site operating costs. The site operating costs include transport and refining costs, royalty charges, mining and processing costs, relevant site general and administration costs and relevant sustaining capital costs. These costs equate to a break even cut off value of US$38/t milled used to define the ultimate pit shell and a marginal cut off value of US$33/t milled or 1.0 g/t gold used to define ore and waste material within the ultimate pit shell.

The marginal site cost is based on an end of mine life low grade stockpile reclaim strategy, reducing the site activity and long term cost base. The mining cost in the marginal site cost represents the stockpile reclaim cost.

Mining factors or assumptions

Estimation of the Lihir Ore Reserve involved standard steps of pit optimisation, mine design, production scheduling and financial modelling. Factors and assumptions have been determined as part of a prefeasibility level study completed in 2020, or are based on operating experience and performance.

Current mining activity at Lihir is via conventional truck and shovel operation, with offshore barge disposal of waste rock and land based and in-pit stockpiling and reclaim of lower grade ore. The current mining activities demonstrate the appropriateness of this mining method as the basis of the Ore Reserve estimate.

Phase 14A design parameters are tabled below:

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Geotechnical slope parameters are based on the detailed analysis of ground conditions and other factors which influence geotechnical performance within the Phase 14A cutback. The Phase 14A slope design parameters are also based on the assumption that a comprehensive system of soil nails, cable anchors, mesh, shotcreting and depressurisation is used to provide additional support to the final wall configuration during cutback development, and that a backfill buttress is used to provide long term support after cutback completion. The design parameters are based on current geotechnical experience and a prefeasibility level study for the cutback mining area.

The Lihir Resource Model utilises LUC to estimate block gold content. This process allows for ore dilution and recovery to be built into the resource model based on the assumption of the selective mining unit (SMU) as the block size. The SMU assumption (20m x 20m x 12m) is based on the mining fleet size and is consistent with a high mill throughput/bulk mining strategy. Due to the LUC approach adopted in the resource model no additional mining dilution or recovery factors have been applied to the Ore Reserve estimate. This assumption is supported by the actual reconciliation between resource model and mill performance at Lihir project to date being within an acceptable uncertainty range for the style of mineralisation under consideration.

The pit optimisation takes into account Inferred Mineral Resource, however only Measured and Indicated Resource is reported in the Ore Reserve estimate. The Inferred Resource represents a small portion of material within the ultimate pit design and both the design and financial model are insensitive to the exclusion of this material.

The selected mining method requires civil engineered wall support as described above to allow access to the Phase 14A orebody. The cutback design also requires mining by a fleet of small equipment owing to the narrow ramp configuration required. Allowances for these activities are included in the preparation of the Ore Reserve estimate.
A backfill buttress required for long term support of the final cutback wall prevents mining of some existing Reserves inventory.

Metallurgical factors or assumptions

The Ore Reserve estimate is based on a maximum 15.5Mtpa comminution rate plant producing gold doré. Ore processing at Lihir involves the main operations of crushing, grinding, flotation, pressure oxidation, leaching and electrowinning to recover gold from relatively high-grade sulphide feed. The Lihir process plant utilises proven technology that is widely used in the gold industry for this style of mineralisation.

The ore processing facility has been operating since it was commissioned in 1996 and upgrades took place during 2011/2012. Comminution circuit operating optimisations and minor upgrades are planned to achieve a 15.5Mtpa plant capacity.

The metallurgical recovery assumption for ore feed to the autoclave is dependent on the gold and sulphide sulphur grades, and dependent on sulphur to calcium ratio and proportion of aged stockpile feed for flotation material. Overall metallurgical recovery is reconciled with historic production data, laboratory test samples for stockpiled ore and reflects a partial oxidation metallurgical operating strategy. Average life of mine gold recovery is modelled to be
81-82%.

The potential impact of the presence of low concentrations of copper on leaching efficiency and cyanide consumption has been assessed and is not considered an issue for the Ore Reserve estimate. Copper levels are generally below 500ppm, and historical performance indicates that levels below 1000ppm show no material impact.

Environmental

Lihir open pit is an operating mine and has been granted an environmental permit for the mining of the Phase 14A cutback.

Infrastructure

The Lihir operation is an operating mine and has the necessary infrastructure in place for its continued operation.

Costs

Capital and operating costs have been determined as part of the prefeasibility study based on estimated operating costs for a drilling, shotcreting and cable bolt installation program. Reserve cost estimates are considered to be pre-feasibility level. Provision has also been made for capital expenditure required for a fleet of smaller mining equipment suited to the cutback access configuration. Life of cutback non-sustaining capital is estimated in the range of US$60-70 million.

No cost impact is expected from deleterious elements. It has therefore not been necessary to include additional costs relating to minor elements when preparing the Ore Reserve estimate.

Transport and refining charges have been developed from first principles consistent with the application and input assumptions for these costs used by the current operation. Refining charges and transport costs are estimated to average US$2.24/oz of gold.

A royalty of 2.0% of gold revenue (net of refining and transport costs) is divided between federal, provincial governments and local level governments and landowners. A mining levy of 0.5% (net of refining and transport costs) is also applied in the preparation of this reserve estimate.

Revenue factors

Long term metal prices and exchange rate assumptions adopted in the December 2020 Reserve estimation process are US$1,300/oz for gold at a AUD:USD exchange rate of 0.75. These assumptions are consistent with Newcrest metal price guideline for December 2020 Ore Reserve period.

Market assessment

Newcrest is a price taker and gold is sold on the open market and subject to price fluctuations. Supply and demand for gold from Lihir is not a constraint in the estimation of the Ore Reserve.

Economic

The Ore Reserve has been evaluated through a financial model. All operating and capital costs as well as revenue factors stated in this document were included in the financial model. This process demonstrated the Lihir Ore Reserve to have a positive NPV.

Sensitivities have been conducted on the key input parameters of costs and recovery which confirm the estimate to be robust. The NPV range has not been provided as Newcrest considers this to be commercially sensitive information.

Social

Engagement with landowners for affected blocks within the cutback footprint and the local community was undertaken through a series of meetings in conjunction with the Mineral Resources Authority (MRA). Approval for the project has been endorsed by block executives as documented in the engagement meeting minutes.

Environmental permitting for the Phase 14A Project has been assessed and approved by CEPA.

Other

Lihir Gold Limited and the Lihir Open Pit are in material compliance with all legal and regulatory requirements.

Naturally occurring risks that might have a material impact upon the Lihir ore reserve are discussed in the risks section of Newcrest's Operating and Financial Review (in the Appendix 4E and Financial Report for the year ended 30 June 2021 which is available to view at www.asx.com.au under the code "NCM" and on Newcrest's SEDAR profile) and include the potential impacts of seismic activity.

Classification

All of the in-situ Ore Reserve is currently derived from Indicated Resources. This classification is based on the density of drilling, the ore body experience and the mining method employed. The only Proved Ore Reserves derived from Measured Resources are those reported in known and quantified stockpiles.

It is the Competent Person's view that the classifications used for the Ore Reserves are appropriate.

Audits or reviews

Golder Associates Pty Ltd (Golder) was commissioned in 2020 to conduct an independent review of the Ore Reserve estimation processes and results that did not include Phase 14A.

Golder concluded that the Ore Reserve had been prepared using accepted industry practice and is considered suitable and reported in accordance with the JORC Code, 2012 Edition.

A competent independent review of the Phase 14A Ore Reserve estimate has been undertaken by Newcrest group planning with no non-compliances or material issues.

Discussion of relative accuracy/ confidence

The accuracy of the estimates within this Ore Reserve is mostly determined by the order of accuracy associated with the geotechnical slope parameters, the Mineral Resource model and the cost factors used.

The Competent Person views the Lihir Ore Reserve a reasonable assessment of the global estimate.