2007 MINERAL RESOURCE & ORE RESERVE EXPLANTATORY NOTES

Transcription

1 2007 MINERAL RESOURCE & ORE RESERVE EXPLANTATORY NOTES The accompanying statement of Mineral Resources and Ore Reserves conforms to the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (The JORC Code) 2004 Edition. Ore Reserves quoted are a subset of Mineral Resources. Independent external and internal reviews are conducted on all completed estimates. Unless stated otherwise, all financial assumptions are in Australian Dollars. Cut-off grade calculations assume metal prices of $600 per ounce of gold and $1.60 per pound of copper with the exception of Kencana where USD $550 per ounce of gold is assumed. Mineral Resources, where appropriate, are further constrained spatially within a notional $800 per ounce of gold and $2.00 per pound of copper shell. As is typical with epithermal deposits, both Cracow and Kencana contain amounts of silver. The Cadia East porphyry deposit contains some molybdenum in addition to the gold and copper reported. CADIA PROVINCE (NSW) CADIA HILL Mineral Resource The Cadia Hill Gold Mine has been in production since June The Mineral Resource was estimated by ordinary kriging and is based on extensive diamond drilling on a notional 50 by 50 metre grid. The resource model incorporates reconciliation achieved from previous production and has demonstrated long term reliability. The resource model is reported on a zero profit cut-off based on $600 per ounce gold and $1.60 per pound copper and current long term mining cost assumptions. While the resource grade model is unchanged from the 2006 statement, there has been a small change to the recovery and financial variables used for the value estimation between the 2006 and 2007 Resources. A notional $800 per ounce gold and $2.00 per pound copper pit-shell has been applied to limit the resource. The Mineral Resource has been depleted for production to 30 June The net result of this depletion and the profit cut-off review is a reduction in Mineral Resources of 26.5 million tonnes for 0.5 million ounces of gold and 0.04 million tonnes of copper. Mill production for the period was 16.6 million tonnes containing 0.3 million ounces of gold and 0.03 million tonnes of copper plus a significant increase in ore material added to stockpile. Ore Reserve The June 2007 Ore Reserve is derived from the re-evaluated 2007 Mineral Resource depleted for mine production during the year. Reconciliation of production demonstrates that the reserve model performance is acceptable. Between the 2006 and 2007 Ore Reserve there have been several changes to input parameters used for reserve calculations. Apart from mining depletion those having the greatest impact are changes in the ultimate pit design. These changes were made to mitigate geotechnical risks. The net result is a decrease in the Ore Reserve by 20.1 million tonnes containing 0.5 million ounces of gold and 0.04 million tonnes of copper. The Ore Reserve estimate is assessed against a profit cut off. The profit calculation takes account of metallurgical recoveries and concentrator, site administration and realisation costs. In order to be classified as Ore Reserve mineralisation must have a profit value of greater than zero and must also be scheduled for milling in the life of mine plan

2 The Ore Reserve estimate was carried out using Whittle Four-X pit optimisation software to select the optimum pit shell for design purposes. After selection of the most suitable pit shell, the final pit extent was designed and then a number of pit cut-back stages were designed and scheduled to enhance net present value. The optimisation of net present value results in stockpiling of low grade mineralisation. This material is subject to oxidisation effects that, over time, reduce metallurgical recovery. Stockpiled material that has insufficient value to cover rehandling, processing and realisation costs is excluded from the Ore Reserve. The average recoveries expected from the concentrator for this Ore Reserve are approximately 82% for gold and 89% for copper. CADIA EXTENDED Mineral Resource The Cadia Extended gold/copper mineralisation is located on the north-west limits of the Cadia Hill Gold Mine. A resource was mined from an Open Pit from January 2003 to June 2004; back-filling of the pit was completed during A new resource model based on existing drill-holes, additional geological knowledge gained from open pit exposures, and achieved production was compiled in This model contains an Inferred Resource considering its potential as a bulk underground mining operation. This work has resulted in the model being reported using an in-situ net value cut-off of $16 per tonne to define a conceptual SLC cave outline. Ore Reserve No Ore Reserve is currently reported for Cadia Extended. CADIA STOCKPILES Stockpiles are reported with the Open Pit and consist of ore mined from Cadia Hill and previously mined from the Cadia Extended pit inventory. The grades are based on in-pit grade control, which determines grade and other rock characteristics. Metallurgical test-work indicates attenuation of recoveries occurs in the stockpiles. A 5% write down of ore tonnes is included for material delivered before the start of the financial year to account for this attenuation and anticipated ore loss in long term stockpiles. The current mine plan reclaims most of the ore delivered during year within two years and no ore loss is anticipated on this material. All short term stockpiles are included as reported by the grade control estimate without attenuation losses. There was a net increase in the Cadia Stockpiles for the year of approximately 7.7 million tonnes containing 0.1 million ounces of gold and 0.01 tonnes of copper. This result is net of mining additions and material reclaimed for treatment throughout the year and anticipated attenuation losses. RIDGEWAY Mineral Resource The Ridgeway resource model was generated in January 07. A geological model for major lithological and structural boundaries was constructed based on drill hole data and knowledge gained from underground exposure and mining experience. This was used to help define a set of mineralised domains. These domains, defined by gold and copper grade, mineralized quartz content and copper mineralogy, were used to control grade interpolation. Gold and copper grades were predominantly derived from 2 metre diamond drill hole - 2 -

3 samples (composited over 4 m intervals). The grades for each domain were interpolated separately using ordinary kriging. The Mineral Resource has been reported using metal price assumptions of $600 per ounce gold price and a copper price of $1.60 per pound. A value cut-off of $16 per tonne has been used for all material above 5040mRL (expected base of the Sub Level Cave operation) and at a value cut-off of $11 per tonne below the 5040mRL level to reflect the intended change in mining method to a block cave. The Mineral Resource has been depleted for mine production to 30 June The material was depleted in its entirety, and remaining production stocks in the cave were estimated by a dilution algorithm utilising dilution entry curves. These factors were used to report the depleted and un-drawn blasted stocks tonnes and grade. Ore Reserve The Ore Reserve for the Ridgeway SLC has been prepared based on the most recent version of the Mineral Resource model. The model was internally audited and reviewed by an external party. The model has been further depleted for stocks mined during FY0607 up to 30th June The net depletion for the Ore Reserve in FY0607 up to 30th June 2007 was 2.8 million tonnes containing 0.2 million ounces of gold and 0.02 million tonnes of copper. This is despite 12 months production for a total 5.7 Mt containing 0.4 million ounces of gold and 0.04 million tonnes of copper. Production was off set by an increase in the mining outline on the 5040 level and an increase in the draw rate of the SLC from 130% to 150% to recover additional metal from the SLC prior to converting to Block Caving in Ridgeway Deeps. For this Ore Reserve estimate, value shells were outlined for each production level based on a value model developed using a $600 per ounce gold price, a $1.60 per pound copper prices and mine gate values. The value model includes the impact of metallurgical recovery and realization costs (concentrate transport, smelter and refining costs). Ore selection used for purposes of generating the Ore Reserves involved incrementally adding material consistent with logical SLC design steps between the Total Production Cost ($25/t) and the current Marginal Operating Cost ($16 per tonne for SLC above 5040RL, $20 per tonne for 5040RL SLC). For the Ore Reserve a DATAMINE macro SLC draw simulator based on observed performance and research findings was used. The DATAMINE macro utilises 10m x 10m columns throughout the orebody to determine draw rates and mined grades. The grade of the ore drawn is determined based on the combination of the ring grade and relevant draw column parameters. The SLC draw simulator has been calibrated against SLC performance observed to date and full scale draw marker trials conducted over the past 4 years. A percentage of the Measured Resource on higher draw percentages, has been classified as Proven Reserve to reflect the confidence level of the grade estimation macro and the operational characteristics of the Sub Level Caving mining method. The average recoveries expected from the concentrator for this Ore Reserve is approximately 83.0% for Au and 88.9% for Cu

4 RIDGEWAY DEEPS Ridgeway Deeps is located immediately below the existing Ridgeway Sub Level Cave (SLC) Mine. It represents the next lift of extraction of the Ridgeway deposit and will be mined as a Block Cave (BC). Mineral Resource The Ridgeway Deeps Mineral Resource was derived from the same geological and block model as Ridgeway (see above). The geological model and revised estimation domains culminated in an extension of the resource model at depth. The net result was an increased resource of 20.0 million tonnes containing 0.5 million ounces of gold and 0.05 million tonnes of copper. Ore Reserve The Ore Reserve estimate was derived from a value model that considered the impact of metallurgical recovery and realization costs (concentrate transport, smelter and refining costs). The ore selection process involved evaluating the draw columns within the Block Cave layout to identify the trade offs between the optimal financial return and the geotechnical and mining parameters. For the Block Cave ore reserve the PCBC draw control estimation software was used. PCBC utilises 10m x 10m x 10m regularised blocks within the orebody to enable a representation of the dynamics of flow within the BC draw columns. This methodology was compared with other industry methods with all predicting results within 10%. All of the Measured Resource within the Block Cave columns have been classified as Proven Reserve due to their location and the confidence level in the grade estimation and operational characteristics of the Block Cave mining method. The average recoveries expected from the concentrator for this Ore Reserve are approximately 80% for Au and 87% for Cu based on test-work results from operating experience. CADIA EAST Updated Mineral Resource and Ore Reserves estimate has been completed for porphyry related gold and copper mineralisation at Cadia East. The Cadia East deposit is located immediately adjacent to the Cadia Hill deposit. It represents porphyry gold-copper style mineralisation east of and below the Gibb Fault which separates the two deposits. The system extends up to 2.5 kilometres east of Cadia Hill from 14000mE to 16500mE (local grid). It is up to 600 metres wide and extends to 1.9 km below surface. The open pit portion of the Mineral Resource extends from near surface where it is covered by post mineralisation Silurian Sediments to the 5150mRL. This section of the mineralisation is dominated by zones of intensely disseminated copper and minor gold mineralisation. Toward the base of the optimised pit shell the resource is dominated by increasing zones of sheeted veins with an increasing gold grade. The underground component of Cadia East mineralisation extends from 700 to 1500 metres below surface, and this part of the resource remains open to the east, west and at depth. Mineralisation at Cadia East is comprised of a body of disseminated and vein controlled gold and copper that grades outward in a predictable manner. The underground component is focussed on a zone of higher grade vein and disseminated mineralisation with native gold, chalcopyrite and bornite as the main metalliferous minerals. Molybdenum is distributed throughout the deposit appearing in association with the other sulphide minerals and within and along vein boundaries

5 CADIA EAST OPEN PIT Mineral Resource During the period September 2006 to December 2006 approximately 6,600 metres of surface diamond drilling was added to the upper Cadia East diamond drilling inventory. This drilling was targeted at gaining additional confidence in the Cadia East Resource grade distribution east of a major fault and geotechnical rock mass characteristics associated with that fault. This was completed in order to upgrade the classification of the Inferred Mineral Resource. Note that a portion of the open pit Mineral Resource is included as Ore Reserves for the underground portion of the deposit as a result of this material being drawn into the designed cave mine as dilution. That is, no double counting has occurred in the reported figures. Confidence in the metallurgical characteristics of the deposit has also been increased as a result of further test-work completed during the last 6 months. Metallurgical recovery models have changed slightly as a result. Further geotechnical (wall slope) design work has also been completed during the period which has improved confidence in the planned depth of the open pit mining method. In addition to the gold and copper reported this resource contains an estimated 0.06 million tonnes of molybdenum at an average grade of 138ppm. The June 2007 Resources and Reserves Statement is unchanged from the 2006 statement. The Mineral Resources estimate is based on the October 2005 resource model. As a consequence of the work outlined in preceding paragraphs a revised Mineral Resource estimate for the Cadia East Open Pit is expected in financial year ending June The revised resource estimate utilises all previous drilling on the Cadia East deposit that dates back to its discovery in The model has been estimated by ordinary kriging within a series of geological and grade constrained domains for gold, copper and molybdenum. The classification of the Mineral Resource is based upon a combination of the density of drilling and geological continuity of domains for gold and copper. The approximate drill density of the Indicated Resource is 80 meters on 50 meter spaced sections along strike. The Mineral Resource has been constrained within a Whittle Pit shell estimated using $800 per ounce gold and $2.00 per pound copper prices. The Mineral Resource has been reported above a calculated notional zero profit value using long term cost assumptions for transport and treatment charges and site costs, and metal prices of A$600 per ounce gold, A$1.60 per pound copper and $7.00 per pound molybdenum. Ore Reserve The Ore Reserve for Cadia East Pit in 2007 is unchanged from the 2006 Ore Reserve and is based on the Cadia East Open Pit October 2005 Mineral Resource model.. The Ore Reserve consists of Probable Ore within the confines of the optimum pit. A further 5.0 million tonnes of material grading 0.88g/t Au and 0.27% Cu may eventually be included within the optimised pit reserves, but is still classified as an Inferred Resource. This material has been incorporated into the base tonnages for optimisation and scheduling purposes, but excluded from the Ore Reserve statement in accordance with Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves. Newcrest has every expectation that planned drilling will upgrade this Inferred Resource. The profit algorithm used to estimate the in situ value of each block incorporates the standard metal price assumptions, along with metallurgical recoveries, concentrate grades and takes into account smelter terms, - 5 -

6 payable metal and freight charges. This algorithm includes the latest ore processing data and assigns metallurgical performance on the basis of ore type. In the planned pit area the Cadia East deposit is a low grade uniformly mineralised orebody immediately to the south-east of the Cadia Hill mine. Mining will be by large scale, low cost mining methods consistent with current mining practices and experience on site. This approach matches the orebody geometries and rock mass characteristics. The optimum pit design is based on geotechnical modelling and practical mining considerations. This design was developed from Whittle Four-X optimisation shells generated at metal prices which provide a margin relative to forecast long term commodity prices. The modelling procedure used in converting the Mineral Resource to an Ore Reserve accounts for sub-grade material where it exists. The modifying factors used to convert the Mineral Resource estimate to the Ore Reserve estimate incorporate sub-grade and waste material as dilution. The dilution factor is based on the minimum selective mining unit as dictated by the proposed mining method. The optimum pit is designed to be mined to a depth some 500m below the valley floor level. Because of the massive, steep dipping configuration of the orebody, the overall pit design has been determined by geotechnical factors rather than orebody geometry. A range of processing rates was assessed and the reserve estimate is based upon treating the Cadia East ore at a nominal rate of 14 Mtpa. The estimate incorporates metallurgical recovery formulae derived from specific test work at Cadia East and processing knowledge from treating similar Cadia Hill ores. The metallurgical recovery varies with grade, but is expected to average approximately 79% for gold and 93% for copper. Sections of the orebody contain high concentrations of molybdenum and metallurgical test work indicates that production of a saleable molybdenum concentrate may be feasible. Work is progressing to incorporate molybdenum estimates into the Ore Reserve. Capital and operating costs are based on Newcrest s direct experience at Cadia Hill. Detailed benchmarking and cost estimation were completed where Cadia Hill costs are not applicable. A sensitivity analysis has been performed using grade, recoveries and costs which have demonstrated the robustness of the project. The Ore Reserve is within the existing mining lease containing the Cadia Hill and Ridgeway operating mines. Waste dump consent conditions have been carefully incorporated into the design and tailing storage requirements taken into consideration. CADIA EAST UNDERGROUND Mineral Resource Additional diamond drilling has been completed to upgrade portions of the existing Inferred Resource to Indicated Resource. As a result of this drilling an additional 275m of strike of the Cadia East Orebody has been upgraded to Indicated Resource. A small section of the strike has also been upgraded from mineralised to Inferred Resource also as a result of the geological interpretation and modelling work. The resource has been reported using identical criteria as the June 2006 report considering its eventual potential as a bulk underground mining operation. This work has resulted in the model being reported using an in-situ net value cut-off of $9/tonne at a gold price of $600 per ounce and a copper price of $1.60 per pound. As in June 2006 the evaluation has also taken into account the potential production of molybdenum as a component of the on site treatment process. In addition to the gold and copper reported this resource contains an estimated 0.06 million tonnes of molybdenum at an average grade of 85ppm. The revised resource estimate and classification has elevated 3.3 million ounces of gold and 0.61 million tonnes of copper from Inferred Resource to Indicated Resource. The total resource also contains an additional 30 Mt of resources than the June 2006 report

7 The revised resource estimate utilises all previous drilling on the Cadia East deposit that dates back to its discovery in The model has been estimated by ordinary kriging within a series of geological and grade constrained domains for gold, copper and molybdenum. The classification of the Mineral Resource is based upon a combination of the density of drilling and geological continuity of domains for gold and copper. Ore Reserve The Cadia East Underground estimate is based on pre-feasibility level mining studies and mineral selection of a panel caving methodology. The underground component of the Cadia East Indicated Resource had previously been converted to Probable Ore Reserves. This was first published in June 2005 and updated in July Given the update in Mineral Resource classification of an additional 275m strike of the ore body a revised Ore Reserve estimate has been completed. Panel and block caving methodologies are well established internationally for extraction of copper porphyry systems similar to Cadia East. Newcrest has undertaken specific studies and reviewed all relevant panel/block caves to compare rock mass characteristics and caving outcomes. Newcrest has a body of work that demonstrates that a panel cave extraction could be reasonably justified and the following Reserve has been compiled. This represents an increase in Ore Reserve estimate by 101million tonnes of ore for a contained 1.7 million ounces of gold and 0.30 million tonnes of copper relative to the previous estimate A value cut-off of $11 per tonne was used on the first 300m of mined strike on the 4850mRL and $9 per tonne on the remainder was used to define the Ore Reserve plan footprint which is considered relative to international standards. This covers all site costs including mining, processing and overheads after allowing for metal recovery and the deduction of transport, smelter, and refining and NSW royalty charges. The respective draw shut off was used to define the vertical draw limits within a 400m physical draw height limit. Established caving draw models have been used to estimate specific dilution impacts on a draw envelope by draw envelope approach. Infrastructure requirements are based on recent Australian and international caving projects. The Cadia East ore is planned to be treated through the existing plant currently treating Cadia Hill ores. The estimate incorporates metallurgical recovery formulae derived from specific metallurgical test work at Cadia East and processing knowledge from treating similar Cadia Hill ores. Capital and operating costs are based on Newcrest s direct experience at Ridgeway, Ridgeway Deeps, Telfer and detailed benchmarking. Operating costs are well within industry practice. The Probable Reserve includes Indicated Mineral Resources only. A conceptual mine plan has also been developed using all the known Mineral Resources and a conversion program is underway to further increase the Ore Reserve. Surface drilling is continuing, evaluating western and eastern extensions of the high-grade core and surrounding lower grade mineralisation. Indications are that with additional drilling the underground resource will expand. The Ore Reserve is within in the existing mining lease containing the Cadia Hill and Ridgeway operating mines. Underground access is well underway thus enabling advance investigation, feasibility studies and the project execution

8 TELFER PROVINCE (WA) Mineral Resources Gold and copper mineralisation at Telfer is bimodal in nature with relatively high grade stratabound reefs and spatially associated lower grade stockworks hosted within Proterozoic sediments. Mineralisation has been intersected in drill holes in Main Dome and West Dome as well as satellite deposits within the Telfer district. These deposits form the basis of the Main Dome and West Dome Open Pit, Telfer Deeps Underground and satellite Mineral Resources reported. Open pit resources are based on sample data from reverse circulation drilling (RC), surface and underground bulk sampling, development mapping and sampling and diamond drilling (in areas beyond the limitations of RC drilling methods). The data used in underground resources are derived from diamond drilling, underground bulk sampling and underground development mapping and sampling. All RC and diamond core is logged and core is photographed. Typical sample length for resource definition RC and diamond samples is one metre down hole. Drill-hole collars, hole paths and diameters were routinely surveyed. Density for each domain was determined using down hole logging techniques and validated using Marcey and air pycnometer techniques. Systematic quality control is applied to all data produced, from the point of collection, through to validation after which it is stored in a comprehensive relational database. All sampling protocols are derived from both ore heterogeneity and geostatistical studies. The grades of gold, copper, cyanide soluble copper, sulphur and other minor elements were analysed using either in-house or commercial assay laboratories. In-house personnel and consultants validated all data used. Extensive statistical and geostatistical analyses were undertaken to determine the suitability of the estimation techniques and to provide appropriate inputs to the interpretation processes. Internal and external review supported the interpretation of the mineralised domains used for the estimate of gold, copper, cyanide soluble copper and sulphur. With the exception of satellites, all resources contain interpreted domains and estimates for arsenic and cobalt, with the addition of nickel and lead estimates in the Telfer Deeps resource. Work undertaken during the Telfer Project Feasibility Study (TPFS), supported by historical production data lead to the application of grade calibrations that had a material impact on the resources reported previously. These calibration factors were quite complex in nature and were intended to correct observed biases related to drill data type and spacing. Calibrations and their application have been extensively reviewed during the year and modified for Main Dome and West Dome open pits and Telfer Deeps underground resource estimates in this report. Information and evaluations which influenced the generation of the 30 June 2007 Mineral Resource statement include: Mining during the financial year that sourced ore material from Main Dome open pit which extracted oxide ore from the upper levels of Stage 3 with transitional and sulphide / fresh mineralisation from the deeper areas within the Stage 2 pit. The percentage of sulphide / fresh mineralisation milled during the financial year represents less than 10% of the total mill reconciled production. Production data was reconciled against resource and reserve models to quantify systematic and special cause errors in previous estimates. Data used to support this reconciliation included grade control RC drilling, mapping and sampling of high grade reefs insitu, underground development and production sampling and mapping, mill performance supplemented by introduction of direct sampling of all mill feed streams to confirm delivered grades

9 Results from this work supported the reduction of remaining data spacing grade calibrations in Main Dome open pit stockwork mineralisation to approximately 4% for gold and copper. This resulted in a decrease of estimated contained metal of 1.5 million ounces of gold and 0.06 million tonnes of copper. In TPFS terms this represents the low case close spaced to bulk sample calibration only and serves to bring the resource in line with tonnes and grade seen in grade control and significantly reduce metal at risk in the estimate. Calibrations present on West Dome open pit stockwork mineralisation were reduced to 4% for gold resulting in a decrease of 1.1 million ounces of gold. Calibrations present on stockwork mineralisation in the Telfer Deeps underground resource estimate were reduced to 4% for gold and copper resulting in a decrease of estimated contained metal of 1.7 million ounces of gold and 0.07 million tonnes of copper. Calibrations that remain in the reported estimate include all calibrations on reef estimates and data type calibrations on Main Dome and West Dome open pit stockwork estimates. Reef exposures in both the Main Dome open pit and Telfer Deeps underground were sampled and mapped during the year to confirm estimated volumes and grades. This data, coupled with extensive historical production data continued to support calibrated reef estimates going forward. As a matter of record remnant metal included in the estimate above base data for reefs is estimated to be 1.1 million ounces (10%) in Main Dome, 0.08 million ounces (2%) in West Dome and 0.16 million ounces (6%) in Telfer Deeps. Data type calibrations relate to an observed bias between lower volume diamond core samples and larger volume equivalent reverse circulation (RC) samples, with the latter almost always being higher and assumed during the TPFS with strong support to be accurate. Where possible this risk has been mitigated by replacing areas supported by diamond drilling with high quality RC drilling. Deeper parts of the resources however are still supported by predominantly diamond core drill samples. As a matter of record remnant metal included in the estimate above base data for data type and data spacing is estimated to be 1.1 million ounces (10%) in Main Dome, 0.4 million ounces (9%) in West Dome, and 0.13 million ounces (5%) in Telfer Deeps. In addition to revision of grade calibrations in the estimates the following changes were made to simplify and further reduce risk in the Main Dome and West Dome Open Pit Mineral Resources: The cut-off approach was standardised to a simple value or profit based marginal break even cut-off which is calculated and applied on a block by block basis taking into account; metal prices of $600 per ounce gold and $1.60 per pound copper, expected metallurgical recoveries, ore processing and off-site costs. All material previously reported in the Measured category was downgraded to Indicated Resource classification to better reflect specifications listed in The JORC Code given production reconciliation to date. All Main Dome strata-bound reef related stockwork mineralisation previously classified as Inferred was also re-classified as Indicated on the same basis. Discordant mineralisation contained within the estimated volume remained unchanged and is largely classified as Inferred. The Telfer Mineral Resources have been the subject of a comprehensive internal and external audit process. Expert advice has been routinely obtained on the subjects of sampling theory, diamond drillhole assay calibration, application of geostatistical methods and mineralisation controls, resource estimation techniques, grade control and mining practices. Stockpiles have been reported with the Main Dome Open Pit Mineral Resource and include all material stockpiled for planned treatment as of the end of the 2007 financial year. The stockpiles have been generated from ore material mined predominantly from open pit and have been adjusted to reflect changes made to the resource estimate in these models

10 The Main Dome and West Dome open pit Mineral Resources are constrained within a pit shell defined using a gold price of $800 per ounce and a copper price of $2.00 per pound determined based on the application of bulk open pit mining methods. Evaluation of the reported Mineral Resource is done using a profit algorithm approach. The Telfer Deeps Underground Mineral Resource for 2007 is comprised of the Sub-level Cave (SLC) Mineral Resource, and the Western Flank Mineral Resource. The SLC Mineral Resource is reported inside breakeven boundaries which reflect the application of bulk underground mining methods and is based on a gold price of $600 per ounce and a copper price of $1.60 per pound. The Telfer Deeps Western Flank Mineral Resource details are not changed. Ore Reserve The Mineral Resource used to generate the Ore Reserve is that described above. The new Mineral Resource has a lower calibration in the stockwork mineralisation in the weathered / transitional and fresh domains in Main Dome and West Dome than that used in previous Ore Reserve estimates. The calibrations remaining for Main Dome contribute approximately 19% of the gold metal within the total Ore Reserve (previously 29%) and for West Dome contribute approximately 4% of the gold metal within the total Ore Reserve (previously 23%) The Main Dome and West Dome Open Pit Ore Reserves are based on use of conventional bulk mining methods. Processing rates have been assessed based on the latest experience from the concentrator which indicates specific ore types can be treated at a higher throughput rate than in the feasibility study. The Telfer Open Pit Ore Reserve is constrained within pit designs based on detailed geotechnical modelling and practical mining considerations and depleted at 30th June These designs were developed from pit optimisation shells generated at metal prices which provide a margin relative to the forecast long term metal prices. Reserves are defined using a breakeven profit algorithm approach. The profit algorithm is a calculation of revenue less processing and realisation costs. Cost and recovery estimates have been made based on the latest metallurgical model which is based on experience to date, TPFS information and anticipated performance in the future. In addition, the Telfer Open Pit Ore Reserve models were re-blocked using an increased block size to better reflect the current mining practices, a simplified metallurgical model and a profit based cut-off grade criteria. These changes were all subject to extensive internal and external reviews during the past 12 months. The combined impact of the modified Mineral Resource, depletion, increased block sizes, change in some material classification, modified cost and metallurgical models, the Main Dome Ore Reserve has decreased by 0.61 million ounces of gold and 0.01 million tonnes of copper. The West Dome Ore Reserve has decreased by 0.56 million ounces of gold. All Proven Ore Reserves have been downgraded to Probable in accordance to changes in Mineral Resource classifications. Within the pit designs there is a small amount of Inferred Mineral Resource. This material is not reported within the Telfer Ore Reserve statement. This Inferred Mineral Resource will be tested by further drilling and some or all of this material may be converted to Probable Ore Reserve through additional resource definition activity. A small portion of the open pit Ore Reserve falls within a pit increment which is dependent on the inclusion of Inferred Resources to meet the economic criteria for production. Newcrest has every expectation that planned further drilling will upgrade these Inferred Resources. Copper grades and contained copper tonnes only apply to those ore tonnes that are treated by flotation methods through the concentrator (i.e. exclude dump leach). Gold grade and contained ounces reflect the sum of both concentrator and dump leach ore. The Telfer Deeps Mineral Resource is amenable to a bulk Underground mining method. A review of potential mining methods is in progress with an SLC Overdraw model used to quote Ore Reserves. The SLC

11 Overdraw method allows maximum depletion of the dilution blanket before narrowing of the cave footprint in the lower levels. Mining outlines for Telfer Deeps were determined based on breakeven boundaries and using the latest SLC recovery and dilution information supported by test work at the Newcrest Ridgeway Operation. Practical mining considerations were considered in determining the outlines. Preliminary review of dilution at Telfer Deeps indicates that it is inline with estimates. Draw marker trials will be completed throughout the year to further validate the recovery and dilution assumptions. The Telfer Deeps Ore Reserve is based on the current Mineral Resource model with reduced grades in the stockwork material. Calibrations currently contribute approximately 12% of the gold metal within the total Ore Reserve (previously 40%). The breakeven boundaries reflect the application of bulk underground mining methods and are based on a gold price of $600 per ounce and a copper price of $1.60 per pound. Mining costs are commensurate with a mining rate of greater than four million tonnes per annum with underground crushing and haulage by shaft, and co-treatment of the underground ore with the Telfer open pit material. The Western Flank is an addition to the Telfer Deeps Ore Reserve estimate. This includes mining of a portion of the mineralised zone, west of the current SLC operation. The mining method assumed is Room and Pillar with an extraction ratio of approximately 50%. Further studies will be completed to identify improvement opportunities in mining recovery. This part of the reserve is based on un-calibrated estimates and contributes 0.16 million ounces of gold and 0.01 million tonnes of copper. The Telfer Deeps Ore Reserve has decreased by 1.0 million ounces of gold, 0.8 million ounces primarily due to reduced resource calibrations and 0.2 million ounces due to depletion and similarly 0.02 million tonnes of copper due to change in calibrations and 0.01 million tonnes of copper due to depletion. Studies continue to evaluate improvement to mining strategies for the current operation and for the potential extensions to the Telfer Deeps mineralisation to the West and below the SLC. These studies are based on results from bulk sampling and drilling to the west and beneath the proposed SLC and on the new Western Flank Mineral Reserve. GOSOWONG PROVINCE (Indonesia) Gosowong is located on the island of Halmahera located in North Maluku Province in the eastern part of the Republic of Indonesia. Gosowong is owned and operated by PT Nusa Halmahera Minerals, an incorporated joint venture between Newcrest Singapore Holdings Ltd 1 (82.5%) and PT Aneka Tambang (17.5%). Tenure over all Gosowong deposits is covered by a 6 th generation Contract of Work No.B.143/PRES/3/1997. For the purpose of reporting Mineral Resources and Ore Reserves Newcrest is reporting 100% of these assets. Actual metal production is marketed by PT Nusa Halmahera Minerals and the owners receive a return through a distribution of profits through dividends. This is a change from Newcrest s previous convention of reporting 82.5% of the Mineral Resources and Ore Reserves for Gosowong. The impact of the change is an increase in Mineral Resource of 0.54 million ounces and in the Ore Reserve a increase of 0.22 million ounces. 1 Newcrest Singapore Holdings is a wholly owner subsidiary of Newcrest Mining Limited

12 Precious metal mineralisation in the Gosowong Province is characterised as low sulphidation, epithermal in nature. The gold grade is high and is associated with similar levels of silver. Gosowong Province ores mined to date have proven to be without contamination issues and metallurgical recoveries greater than 95% have been demonstrated through conventional leaching methods. Tailings are subject to a detoxification process prior to storage in a conventional dam system. Waste rock contains some potentially acid forming material (PAF) which is identified and classified in the mining process before encapsulation in design specific cells located within conventional valley fill waste dumps. These dumps are progressively rehabilitated and revegetated as sections are completed. The resource definition process applied at Gosowong is based on systematic diamond drilling with some infill reverse circulation used when appropriate. It has been established that mineralised shoots drilled to a notional spacing of approximately 50 x 50 metres can generally be classified as Inferred Mineral Resource as defined by the JORC Code. Similarly drill spacing of 25 x 25 can normally support an Indicated classification. Due to the extremely high grades present at Gosowong Mineral Resources are not normally classified in the Measured Resource category unless they have been drilled to 12.5 x 12.5 or grade controlled. 1 Newcrest Singapore Holdings is a wholly owner subsidiary of Newcrest Mining Limited Diamond core is logged and photographed prior to sampling. Sampling protocol is based on heterogeneity testing undertaken from time to time and is generally based on half core. Most core intercepts are HQ in size by design however a minor percentage of smaller NQ intercepts are present in the database due to drilling difficulties that can occur in the Gosowong environment. Core recovery is monitored carefully. Samples are assayed for gold and silver at the on site laboratory using fire assay (FA50) with AAS finish. Where fire assay indicated gold grades are greater than 80g/t, a gravimetric method has been applied. Selected samples are sent off site for analysis of minor elements and base metals by ICP scan. Each batch is submitted with blind standards, repeats and blanks. Results from these control samples are used to generate routine QA/QC reports which can be used to control the process and to demonstrate the veracity of the database at any time. This process is audited both internally and independently on a regular basis. KENCANA UNDERGROUND Three economic mineralised shoots have been identified to date within the Kencana system ; K1, K2 and K Link. Revised estimates of Mineral Resources for the K1 and K2 deposits has been undertaken. These estimates are based on revisions to previous resource models using new data from grade control drilling / underground mining (K1) and surface drilling (K2). The K1 model has been reported with mining depletion as at 30 th June 2007 while the K2 model represents data available as at 31 st March The K Link resource quoted below is as at 30 th June 2006 as insufficient new data has been generated to warrant a revised estimate at present. Mining is yet to commence on K2 and K Link and infill drilling continues. The Kencana Mineral Resource is reported above the marginal breakeven cutoff grade of 6g/t gold. In total the revised estimates represent a 0.04 million ounces of gold increase from the June 2006 Resource statement at 100% equity after allowing for mining depletion of 0.34 million ounces of gold in FY07. K1 Resource The K1 Mineral Resource is estimated to be 1.45 million ounces of gold based on a marginal cut-off grade of 6g/t Au. This represents a 0.57 million ounces of gold reduction from the previous public statement (June 2006) that is due to both revision of the estimate based on additional drilling / development data (-0.235Moz Au) and depletion from mine production FY07 (-0.335Moz Au). Confidence in the estimate has been significantly increased with the infill drilling and all previous K1 Inferred Resources, which constituted 56% of estimated tonnage in June 2006, have been upgraded to Indicated Resource status

13 The K1 estimate has been made from a combination of drilling data spaced on nominal 25m centres and ore drive sampling data obtained from mining activity. Grade interpolation has utilized either Ordinary Kriging 2D Accumulation methods for the resource model based on drilling or 3D Inverse Distance methods where grade control drive sampling and mapping data was available (approximately sublevels 1 5). Following detailed data analysis and review the K1 estimate is considered robust with regard to contributing data. Drilling data assay information uses uncut grades while drive sampling data has been cut to reduce the impact of extreme grades. There has been a material adjustment to the geology model which underlies the drilling based resource estimate. An additional geological domain has been constructed in the drilling resource model based on observable geology parameters. The zone constrains the extremely high grade zones within the main zone of K1 and is titled the K1 Bonanza Zone. The constraint of the samples within this zone contributes to restricting the extent of the influence of such samples on the model during interpolation (kriging) and acts to reduce contained gold in the overall estimate by approximately 0.2 million ounces. The need to apply this constraint arose from experience gained during ore drive development during 2006 when models were reconciled with production. The K1 Mineral Resource remains open down plunge to the south and has not been fully tested at depth. K2 Resource The K2 Mineral Resource is estimated to be 1.52 million ounces of gold based on a marginal cut-off grade of 6g/t Au. Infill drilling in K2 has increased contained gold by 0.61 million ounces and the average grade of the deposit has risen significantly. Given the intensity of infill drilling activity to date in FY07 approximately 80% of the known deposit has been upgraded in confidence to Indicated Resource status. There has been a material adjustment to the geology model which underlies the Mineral Resource estimate compared to the 30 th June 2006 statement. An additional geological domain has been constructed based on observable geology parameters. The zone constrains the extremely high grade zones within the main zone of K2 and is titled the K2 Bonanza Zone. The domaining of the samples within this zone contributes to restricting the extent of the influence of such samples on the model during interpolation (kriging) and acts to constrain contained gold in the overall estimate as with K1. This issue was recognised as being relevant to K2 and estimation was undertaken with due prudence. All other data acquisition and resource estimation practices are unchanged compared to current K1/K2 estimation practices. The estimates have been made from drilling data spaced on nominal 25m centres using Ordinary Kriging 2D Accumulation methods. Following detailed data analysis the K2 estimate is considered robust with regard to contributing data and is hence made on uncut grades. This revision is an interim estimate as drilling will continue around the edges of the K2 deposit until late 2007 when a new estimate will be undertaken and released. All Inferred Resource material will be converted at that stage. The K2 Mineral Resource remains open down plunge and to some extent along strike. K Link Resource The K Link Inferred Mineral Resource remains unchanged at 0.18 million ounces of gold based on a marginal cut-off grade of 6g/t Au. Infill drilling of K Link will be undertaken in FY0708. Ore Reserve Ore Reserve for the expanded Kencana field comprises K1 and K2 ore bodies. The Ore Reserve is based on the March 2007 mine design for K1 and the preliminary pre-feasibility designs for K2. Both ore bodies utilise the underhand cut-and-fill mining method. Significant changes have occurred between the June 2006 and June 2007 Ore Reserves. Additional geological drilling (and remodelling) has upgraded the K1 June 2006 inferred and unclassified material to indicated, and a significant proportion of the K2 orebody has been drilled out to Indicated level. K Link has been included in the Mineral Resource as an Inferred Resource

14 The global mine design has been based on a breakeven cut-off grade of 13g/t Au. Where ore development is required to mine through lower grade material to access material above the cut-off grade, an incremental cutoff grade of 6g/t Au has been used to determine whether the lower grade material is ore or waste. The incremental cut-off grade includes the processing cost and the additional haulage cost for ore. The net change in the Ore Reserve for the period was an increase of 1.4 million ounces of gold comprised of: K1 increase of 0.06 million ounces resulting from change in equity reporting, remodelling, and depletion; and K2, increase of 1.3 million ounces of new reserves. CRACOW GOLD MINE (QLD) Cracow Gold Mine is an unincorporated joint venture between Newcrest (70%) and Sedimentary (30%)- a wholly owned subsidiary of Lion Selection Group. The Cracow Mineral Resource is a combination of Mineral Resources estimated at the Royal, Crown, Klondyke North, Sovereign and Kilkenny shoots. Material changes to the Mineral Resource at Cracow during the period include the re-modelling (-3,000 ounces of gold) and adjustment for mining depletion (-0.10 million ounces of gold) at both the Crown and Royal Shoots. A number of sub-parallel structures and splays off the Crown Shoot structure are now interpreted from the additional diamond drilling information. Only one of these structures called the BAZ Vein, which is a sub-parallel vein located on the footwall of the main Crown Shoot, has sufficient drill intercepts to enable a small resource to be generated and is included as part of the Crown Resource in the above table. The Sovereign Shoot and the Klondyke North resources remain unchanged since the previous reporting period, while the Kilkenny Shoot is a new addition to the resource inventory (+0.14 million ounces of gold). All the Mineral Resources have been estimated using 2D estimation methods, except in the areas of the Royal and Crown with detailed face sampling and mapping data, where a 3D estimation method has been used. The 2D metal accumulation models were completed by modelling horizontal thickness (width) and grade x width accumulation using drill-lhole information. The 2D estimates interpolated the three variables, horizontal thickness, gold accumulation and silver accumulation by Ordinary Kriging, and the gold and silver grades where back-calculated by dividing the estimated accumulation by the estimated horizontal width. In the areas of the 3D model gold and silver grades have been interpolated using Ordinary Kriging. Comprehensive QA/QC programs have been conducted on all resources using standards, check samples, blind resubmissions, barren flush analysis, external laboratory checks and screen fire assaying. No issues with the gold and silver analysis or sample preparation are indicated. Gold grade was determined by 50g fire assay. Surface drillhole collars are surveyed after hole completion and a single shot Eastman camera has predominantly been used for down-hole survey. Core orientations were completed using the Ballmark system and the Chinagraph spear method. Underground drillhole collars were accurately located by Total Station EDM survey in the drill cuddies and down-hole position was located by a Flexit survey tool. No core orientations were completed on underground diamond holes. Royal Development of the decline and all ore-drive levels was completed during the year down to the bottom level at the 1869mRL and remaining mining activity is now stoping only. Infill underground diamond drilling continued throughout the year as drill positions became available and all planned infill resource drilling has been completed. All holes were drilled at an LTK60 (43.9mm) core size. An updated Mineral Resource estimate of the Royal Shoot was completed in December The new estimate for the Royal Shoot portion of the Royal-Klondyke lode is located between 4,475 4,900mN and