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St Ives Gold MineTechnical Short Form Report31 December 2011

Gold Fields: St Ives Gold Mine – Technical Short Form Report 2011 3

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Salient features

¨ Mineral Resources at 5.3 Moz.

¨ Mineral Reserves consistent post depletion at 2.8 Moz.

¨ Full production achieved at Athena in September 2011.

¨ First ore intersected at the new Hamlet mine and development of new infrastructure making good progress.

¨ Neptune Mineral Resources and Mineral Reserves continue to grow.

¨ Life of Mine extended to 2018.

The St Ives tenement holdings are located in the highly prospective Norseman-Wiluna Archaean Greenstone Belt, mining a dynamic mix of open pit and underground operations.

Accelerated greenfields exploration initiated in 2011 realising new targets and options.

Geographic location

St IvesTenements

Western Australia

• Derby

• Leinster

• Kalgoorlie

• Perth

Yilgarn Craton

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Geographic location IFC

1. Overview Page 1

2. Key aspects Page 2

3. Operating statistics

4. Geological setting and mineralisation Page 4

5. Mining Page 6

6. Projects Page 7

7. Mineral processing Page 7

8. Sustainable development Page 8

9. Mineral Resources and Mineral Reserves Page 9

10. Regulatory codes Page 13

11. Competent Persons Page 13

12. Key technical staff Page 14

13. Brief history Page 17R

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1. OverviewThe St Ives Gold Mining Company (Pty) Limited is wholly owned by Gold Fields Limited and is situated within the highly prospective Norseman-Wiluna Greenstone Belt in Western Australia. The St Ives operations are situated within mining tenements comprised of 277 mining titles (54,749 hectares), three mineral titles (364 hectares), 14 exploration licences (27,572 hectares), 45 prospecting licences (7,190 hectares) and 19 miscellaneous licences (14,634 hectares) for a total area of approximately 104,509 hectares.

St Ives represents a solid base for growth in Australia and is an important contributor to the Gold Fields vision, “To be the global leader in sustainable gold mining,” with a target contribution from the Australasia Region of 1,0 Moz per annum in production or in development by 2015.

Declared Mineral Resources at the St Ives Gold Mine decreased by 450 koz primarily due to depletion and closure of the Belleisle mine during 2011, while the Mineral Reserves, inclusive of a depletion of 520 koz since December 2010, was steady at 2.8 Moz. Changes to Mineral Reserves from December 2010 were dominated by discoveries at Neptune, Cave Rocks, Trinidad and the Britannia Footwall project, with nominal growth at Hamlet and Athena.

The St Ives Life of Mine (LoM) was extended by an additional year, as discovery and opportunities associated with the higher gold price contributed towards additional Mineral Reserves. Ongoing exploration achievements and increased drilling of the mine’s extensive greenfields project pipeline in a major well-endowed gold camp provides the basis for further Mineral Resource extensions and discovery.

This technical short form report reflects the latest consolidated Life of Mine plan input parameters, coupled with an updated Mineral Resource and Mineral Reserve statement as at 31 December 2011. All Mineral Resource and Mineral Reserve figures reported are managed unless otherwise stated and Mineral Resources are inclusive of Mineral Reserves.

Note: For abbreviations refer to page 28 and for glossary of terms refer to page 29 – “Mineral Resources and Mineral Reserves Overview 2011”.

1

Cover image:

Lefroy Mill


2. Key aspects

Independent audit Figures reported in this declaration are as reviewed by independent external consultants as at 31 December 2011 (Optiro Pty Ltd for Mineral Resources and AMC Consultants Pty Ltd for Mineral Reserves). Gold Fields has been informed that the audit identified no material shortcomings in any process by which the St Ives Mineral Resources and Mineral Reserves were evaluated

Prepared by Gold Fields Limited in compliance with the SAMREC Code (2007 edition)

Effective date 31 December 2011

Source of information This Technical Statement is a summary of the internally sourced document entitled December 2011 St Ives Competent Persons Report

Personal inspection Personal inspection is conducted by the Competent Persons as listed, who are full-time employees of Gold Fields Limited

General location The St Ives operations extend from 5 to 25 kilometres south-southwest of the town of Kambalda in Western Australia, approximately 630 kilometres east of Perth at latitude 31° 12’ S and longitude 121° 40’ E. The nearest major settlement is the town of Kalgoorlie situated 80 kilometres to the north. Well-established power, access roads and supporting infrastructure exist in the area

Climate St Ives is situated in an area of arid bush land. While occasional storm events may cause minor delays to open pit mining operations, the climatic conditions do not materially impact on the normal operations of the site

Licence status and holdings

St Ives controls exploration and mineral rights over a total area of 104,509 hectares (total of granted tenements) and has security of tenure for all current exploration and mining leases that contribute to future Mineral Reserves.

Operational infrastructure St Ives currently operates four underground mines accessed via declines and several open pits, a centralised administrative office, an engineering workshop and Mill/CIP processing plant with a supplementary Heap Leach processing plant

Deposit type Archaean orogenic greenstone gold hosted in a number of different styles of mineralisation

Life of Mine (LoM) It is estimated that the current Mineral Reserve will be depleted in 2018

Environmental/Health & Safety

The mine maintained AS4801:2000 occupational health and safety management system certification and ISO14001:2004, (environmental management system) certification. St Ives was certified as fully compliant to the International Cyanide Management Code on 3 June 2009

Reporting codes Gold Fields reports its Mineral Resources and Mineral Reserves in accordance with the South African Code for the Reporting of Exploration Results, Mineral Resources and Mineral Reserves (2007 SAMREC Code), and other relevant international codes such as SEC Industry Guide 7, JORC Code and NI 43 – 101. The Mineral Resources and Mineral Reserves are underpinned by an appropriate Mineral Resource Management process and protocol to ensure adequate corporate governance in respect of the intent of the Sarbanes-Oxley Act

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3. Operating statistics

UnitsDec

2011Dec

20101 June2010

June2009

June2008

Open pit mining

Total mined kBCM 7,977 3,269 13,464 12,220 13,845

– Waste mined kBCM 6,387 2,508 10,850 9,921 11,807

– Ore mined kt 4,307 2,053 6,643 5,799 5,143

Mined grade g/t 1.8 1.9 1.4 1.5 1.7

Strip ratio (volume) waste:ore 3.4 3.3 4.2 4.3 5.8

Underground mining

– Ore mined kt 1,768 904 1,444 1,222 901

– Mined grade g/t 4.7 4.9 4.7 5.1 5.2

Processing

– Mill tonnes kt 4,793 2,419 4,766 4,821 4,647

– Heap leach tonnes kt 1,952 866 2,052 2,441 2,586

Total tonnes kt 6,745 3,284 6,819 7,262 7,233

– Mill head grade g/t 3.0 3.2 2.7 2.8 2.7

– Heap leach head grade g/t 0.9 0.8 0.9 0.8 0.9

Total head grade g/t 2.4 2.6 2.2 2.1 2.0

– Mill yield g/t 2.8 3.0 2.5 2.5 2.5

– Heap leach yield g/t 0.5 0.5 0.5 0.5 0.6

Combined yield g/t 2.1 2.3 1.9 1.8 1.8

Plant recovery factor – Mill % 94 94 93 91 93

– Heap leach % 55 58 56 56 64

Gold Produced

– Mill koz 433 230 389 394 371

– Heap leach koz 32 13 32 37 47

Total gold producedkoz 465 243 421 428 418

kg 14,449 7,557 13,097 13,322 12,992

Financials

Operating cost A$/oz 867 781 832 806 644

Total cash costA$/oz 873 757 806 805 649

US$/oz 901 710 710 596 582

Capital expenditure A$ million 177 59 117 93 120

Notional cash expenditure (NCE)A$/oz 1,248 1,025 1,110 1,023 932

US$/oz 1,287 962 978 757 836

General

Employees (TEC) number 796 778 766 699 661

Mineral Reserves Mt 37.9 32.7 30.6 30.1 25.9

Mineral Reserve Head Grade g/t 2.3 2.7 2.3 2.4 2.3

Mineral Reserves Moz 2.8 2.8 2.3 2.3 1.9

Expected Life of Mine years 7 6 4 4 4

1 Figures shown represent the six months to 31 December 2010. Rounding off of figures presented in this report may result in minor computational discrepancies. Where this occurs it is not deemed significant.


In comparison to other greenstone belts in the Yilgarn Craton, the Norseman-Wiluna Belt is highly mineralised, particularly in gold and nickel.


St Ives is situated in the Norseman-Wiluna Greenstone Belt, which is part of the Yilgarn Craton, a 2.6 Ga well mineralised granite-greenstone terrain in Western Australia. The rock types in the belt comprise abundant tholeiitic and komatiitic volcanic rocks, chert, sulphidic and albitic sedimentary rocks, and a chain of discrete felsic volcanic centres.

The gross structure is markedly linear with north-north-west trending strike-slip faults and other tectonic lineaments traceable for hundreds of kilometres, which disrupt the greenstone into fault-bounded domains. The generalised stratigraphic sequence comprises three mafic-ultramafic units, two felsic volcanic units and an uppermost epiclastic sequence.

There has been a complex and long-lasting history of structural deformation incorporating up to seven significant stages (D0-D7) during and after regional metamorphism. The gold mineralising episodes are interpreted to have occurred during thrusting and faulting associated with the D2-D3 structural events.

Metamorphism has affected all rock types and ranges from low temperature prehnite-pumpellyite facies to high temperature-pressure amphibolite and granulite facies. Flexures and irregularities in many local and regional shear zones are interpreted to be the major control on location of the majority of economic gold deposits in the belt.

Much of the Yilgarn Craton is deeply weathered and partially covered by Tertiary and Quaternary regolith. Pre-Tertiary lateritic horizons are variably exposed, eroded or buried by later deposits that have in turn been lateritised.

Local geologySt Ives lies within the Kambalda domain, a subset of the Norseman-Wiluna Belt. The Kambalda domain is bound by the north-north-west trending Boulder-Lefroy fault (BLF) and Zuleika shear. The region has undergone four compressional events predated by early extension and has been

4. Geological setting and mineralisation

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metamorphosed to upper greenschist or lower amphibolite facies.

The main structural feature of the St Ives area is the gently south-plunging Kambalda anticline, which

extends 35 kilometres from the south end of the Kambalda dome to the Junction Mine. The majority of known gold deposits are proximal to the trace of the anticlinal axis. A major second order structure known as the Playa

METRES

10 500

10 000

9 500

9 000

8 500

8 000

7 500

7 000

6 500

6 000

5 500

5 000

4 500

4 000

EPICLASTICS

VOLCANICLASTICS

AU

AU

AU

KambaldaGranodiorite

AU

NI

PARINGABASALT

BO

ULD

ER -

LEF

RO

Y A

ND

MER

OU

GA

L FA

ULT

S

Santa Ana Sirius

Revenge Defiance Conqueror Thunderer Orchin

Mars Minotaur Agamemnon

Intrepide Redoutable Belleisle

Beta-Hunt

MerougilCreekBeds

JunctionArgo

Hamlet Athena

West Revenge/NRKNorth OrchinOld VictoryRepulce

BlackFlag

Beds

CondenserJunctionDolerite

DefianceDolerite

Kapal SlateDevon Consols

Basalt

Flames

Selected Gold Mines

KambaldaKomatiite

LunnonBasalt

Tripco HillKomatiite

Silver Lake Peridotite

2690 ± 5 Ma

2692 ± 4 Ma

<2720 ± 105 Ma

2709 ± 4 Ma

ZIRCONAge Dating

<2664 ± 6 Ma

2662 - 2669 Ma

2680 ± 8 Ma

2676 ± 4 Ma

Newman •

Caims •

Perth •

• Derby

• Brisbane

• Sydney

• Canberra

SOUTHAUSTRALIA

ST IVES

NEW SOUTH WALES

VICTORIA

QUEENSLAND

NORTHERNTERRITORY

YILGARN CRATON

WESTERNAUSTRALIA

Adelaide

• Hobart

Granitoids and Gneiss

Greenstone

Major Faults

Proterozoic unconformity

Province Boundary

• Darwin

Melbourne•

•

55

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shear splays off the BLF shear zone and can be traced through the St Ives field for a distance in excess of 10 kilometres.

Most of the St Ives ore bodies mined to date are associated with third order splays off the Playa shear – notable exceptions being Argo and Santa Ana which are situated on the western limb of the anticline. Mineralisation typically occurs where these structures intersect favourable rock units, with chemical or rheological contrasts combining with structural flexures to form the most important local controls to mineralisation. The stratigraphic succession in the Kambalda domain comprises Kalgoorlie group volcanic rocks and the Black Flag group felsic volcanic and sedimentary rocks overlain by the post-tectonic Merougil beds unit.

The most common host rocks of gold mineralisation are dolerites such as the Defiance, Condenser and Junction dolerites. Granophyric dolerite and Kapai slate tend to host the highest grade mineralisation. The Paringa basalt and Kambalda komatiite host deposits in discrete shear structures that are moderate in both tonnage and grade. Low to moderate-grade, high-tonnage mineralisation is commonly developed in porphyries, which are found in almost all deposits.

Hydrothermal alteration and associated gold mineralisation was synchronous with deformation on a network of shear zones. Alteration is concentrated in 10 centimetre to 300 metre wide halos around shear zones. Gold is commonly associated with pyrite or granular pyrrhotite.

There are several styles of gold mineralisation at St Ives. The individual deposits may contain more than one of these styles:

¨ Lode mineralisation: Archaean lode mineralisation typically consisting of 0.5 to 20 metre wide mesothermal vein complexes that may also have hydraulic breccias and/or mylonites indicating movement on a shear;

¨ Supergene mineralisation: Broad zones of flat-lying gold mineralisation in weathered Archaean and overlying Tertiary sediments; and

¨ Palaeoplacer mineralisation: Placer deposits hosted by palaeochannels in the unconsolidated Tertiary sediments which overly the Archaean basement.

Exploration and drillingThe St Ives exploration strategy incorporates the integration of geological information and knowledge of ore-forming systems to identify targets with the greatest potential for conversion from endowment, thus maintaining a high-value project pipeline (on-mine exploration: Milestone pyramid). This strategy includes:

¨ Greenfields – enhance the capacity and data consolidation to identify additional targets based on new knowledge and application of current research and development initiatives. In 2011, St Ives drilled approximately 80,000 metres in early stage exploration;

¨ Continued support, application and integration of company/industry-funded research projects aimed at understanding the structural, geochemical and ore mineralising fluid pathways applicable to the St Ives gold camp in conjunction with our research partners CSIRO;

¨ Convert and integrate existing knowledge and research into three-dimensional information data sets to identify additional target areas internally to maximise the existing sites geological endowment;

¨ Convert existing knowledge and expand the future potential of the Argo-Athena-Hamlet complex environs;

¨ Increased targeting based on understanding of the structural and macro boundary modelling of ore shoot development at various mine sites; and

¨ Extensional drill-outs and conversion of Inferred Resources to mine defined Indicated Resource levels to enable accurate geology and resource models to be completed to enable optimised mine design, schedules and profitable gold production.

St Ives maintains rigorous quality assurance and quality control (QA/QC) protocols on all of its exploration programmes using best industry practice in data acquisition, reputable external laboratories and having sign-off by Competent Persons under the 2007 SAMREC and 2004 JORC Codes.

Current most Prospective Projects listed. Black are Open Pit projects and yellow are Underground targets

On-Mine exploration: Milestone pyramid

Yorick,Poseidon,

North Shore,Junction Target 4,

Incredible, Beta Porphyry

Tramways, Junction West 1, Cyclops, Juggernaut,

NW Poseidon, Foster, Melech, Foster 3, Foster 17,

Paluma Sunrise, LT17 South

Heron East, Heron South, Junction Target 5, Bartok, Zadok, Dorado, Foster 2,

Junction Target 3

Drill targetdefinition

39 Active Milestone 3 (Economic intersections and

structure of deposit coming together)

Anomalydefinition

137 ActiveMilestone 2 (Early stage

indications of mineralisation)

Projectgeneration

43 ActiveMilestone 1

(Conceptual targets)


5. Mining

Gold mineralisation at St Ives is mined via both open pit and underground methods to depths generally not exceeding 500 metres below surface. As many of the operations involve mining deposits on or under Lake Lefroy (a shallow salt lake), extraction requires construction of berms and other earthworks to provide access, short-term stockpile areas and to prevent water intrusion.

Mining methodsOpen pit mining by conventional drill and blast/truck and shovel is employed at all open pits. Grade control is generally by inclined RC drilling. Open pit projects may include 10 to 40 metres of unconsolidated sedimentary overburden, which does not require drill and blast, but needs hard rock to be imported for sheeting to provide equipment access during mining, and/or dewatering of the sedimentary overburden prior to mining. Load-and-haul is by 140 tonne dump trucks and 150 to 250 tonne excavators in backhoe and/or face shovel configuration. Mining benches vary from 5 to 10 metres, which is excavated in five passes (flitches) of about 2.5 metres per flitch. Gold mineralisation is mined selectively to cut-offs and segregated into grade ranges as required to balance the ore production and processing capacities on site and maximise cash flow from operations.

Underground mines at St Ives are commonly extensions of open pit mines. Underground operations are characterised by common features which allow a high level of standardisation in operating strategy, mine design, stoping methods, mining equipment and utilisation. Mines are accessed via declines, with additional development of raises for return airways and ladderways as a second means of egress. Drives are developed to access the ore and future stoping production areas.

Underground mining at St Ives is predominantly mechanised and is conducted by long-hole open stoping (LHOS), with subordinate cut-and-fill and room-and-pillar stoping for the shallower dipping ore bodies. The use of paste fill in conjunction with LHOS is applied where mandated by geotechnical factors. Development and stoping utilises electric-hydraulic drilling jumbos and rubber-tyred diesel-powered LHDs, while trucks are used for load-and-haul operations. Ore from both open pit and underground operations is transported with road trains from individual mining operations to the central St Ives processing facilities.

Mine planning and schedulingMineral Reserve definition processes for open pit and underground operations are essentially similar. Cut-off grades are applied to define potentially economic mining panels based on direct mining and processing costs, group set commodity prices and other parameters. The economic viability of future mining panels is then tested by determining whether the optimal margin after applying the appropriate cut-off grade is sufficient to cover the required capital development costs and provide a return on investment.

Open pit planning entails the input of economic parameters and physical constraints into optimisation software to generate a series of nested pits, from which an optimal shell is selected. Detailed design is then undertaken to confirm the mineability of the optimised shell.

Underground mining methods are largely determined by the geometry of the mineralised zones and the evaluation may involve review of more than one method. Mine design and scheduling is done utilising sophisticated software.

Mine planning is based on three-dimensional block models of in situ mineralisation, with allowances made for minimum mining widths, dilution and ore loss appropriate to the mining method being considered.

Infrastructure, waste disposal and ore stockpile management requirements are incorporated into the planning process. Ore stockpile management at St Ives strives to optimise the metallurgical blend requirements to the Lefroy Mill and the Heap Leach facility, with regard to material types and grade management, to maximise cash flow from the operations.

St Ives currently operates four underground mines accessed via declines and several open pits, a centralised administrative office, an engineering workshop and Mill/CIP processing plant with a

supplementary Heap Leach processing facility.

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6. Projects

Ongoing infrastructure development to meet current and future mine extensions together with extending the lives of individual mines through focused extensional exploration and development continue. Other future projects are the new Bellerophon open pit and potentially the establishment of the Neptune open pit. Feasibility studies will be completed during 2012 on the Neptune deposit together with possible integration into the existing open cuts and extension to the south is under consideration.

Heap Leach expansionThe capacity of the Heap Leach pad reached final design capacity (2009) based on the current throughput rate. Ongoing production is now managed by the removal of spent (leached) ore from the existing pads and the restacking of new material. Site trials since September 2009 have indicated that removal of the current spent material and re-usage of the pads will be environmentally sound and economically viable despite a number of initial transitional issues. A strategy of flushing, removing, restacking and leaching is employed to treat the available and future supply of the heap leach ore.

Notwithstanding the above, consideration for expansion of the Heap Leach plant and the processing of low-grade material remains an option.

Tailings storage facilityA fourth tailings storage facility (TSF 4) is currently under construction within a phased number of cells. The initial paddock is planned for operational deposition from mid-2012 and subsequent cells will be commissioned on an ongoing basis as required over the next few years.

The current major mine expansion project is located at the new Hamlet deposit, which is in the production build-up phase. Athena is now a fully fledged new mine, having reached commercial levels of production in late 2011. A number of ancillary ventilation shafts and paste fill plants are

currently being constructed to service these two new mines.

Nep

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7. Mineral processing

The Lefroy Mill was commissioned in December 2004 and achieved design capacity within seven months. It treats medium to high-grade ore through a 4.8 Mtpa variable-speed dual direction 13.5 MW sag mill with wraparound motor. Oversize from the mill (scats) is in closed circuit with a 140-tonne-per-hour pebble crusher. A gravity circuit recovers the gravity-recoverable gold from the milling circuit and the concentrates are treated separately through to bullion form. The mill cyclone overflow product reports to a five-stage leach circuit consisting of mechanical agitators, reagent addition and oxygen sparging.

Leached slurry passes through the six-stage carousel pump cell adsorption plant and subsequent five-tonne capacity acid wash, elution and electrowinning circuits which produce calcine ready for smelting. Bullion is shipped by road and air to the refinery in Perth. Tailings are alternately deposited on two tailings facilities which are constructed upstream and are of paddock type.

St Ives utilises two separate beneficiation processes, a CIP plant (Lefroy Mill) and a Heap Leach facility for the treatment of mined ore and stockpiles.

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Delta Island South

Aga / Delta / Revenge

Neptune

Redback

NeptuneSouth (A5)

Au (g/t)From To0.0 0.00.0 0.10.1 0.50.5 1.01.0 2.02.0 3.03.0 6.06.0 999.0

Z

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8. Sustainable development

St Ives strives to achieve and maintain outstanding health and safety performance through the participation of all employees and the application of safe, innovative processes and technologies, within a framework of OHSAS 18001, which is an international occupational health and safety management system standard against which our management systems are assessed and certified.

St Ives remain committed and supports the Gold Fields strategy of sustainable development and one of the highlights of 2011 was the successful application and approval of the beyond 2010 mining application on Lake Lefroy. This approval obtained in late November 2011 is the result of three years consultative work with all government and local interested and affected role players that included environmental review of potential mining activities that may impact on the Lefroy Salt Lake at St Ives. The approval, with supporting strategies and commitments by the mine, allows the opportunity to increase mining operations and pit dimensions within the Lake Lefroy confines to take advantage of higher gold prices and ongoing successful discovery.

St Ives actively assists staff, through ongoing training and development, and during 2011 areas of focus included the roll-out of a new consolidated reporting and review safety system (INX), risk awareness and management training, as well as enhanced safety visibility and awareness programs. The ZIP programme (Zero-Incident Process) continues to support and encourages all employees though a process that gives the site the opportunity to reach the goal of zero incidents. It empowers people to be able to take control of their personal

safety. ZIP does this by giving staff an insight into the way their brain works and how they can use it more effectively to keep themselves safe.

At St Ives the consideration of our activities in a manner which minimises our environmental and stakeholder impact is fundamental to our operations and the way we do business. The operation is committed to responsible stewardship of natural resources, proactive engagement with all stakeholders and behaving in an environmentally responsible manner. This is demonstrated through our commitment to continuous improvement of the site management systems and operational performance. This is evident through our ISO 14001:2004 certification and compliance with our licence to operate.

Safety statisticsClass Units June 2008 June 2009 June 2010 Dec 20101 Dec 2011

Fatalities (No) 0 0 0 0 0

Fatality rate (per mmhrs) 0 0 0 0 0

LDIFR (per mmhrs) 1.8 0.8 4.1 3.9 2.91 For six months to December 2010.

At St Ives we strive to create a workplace culture of “zero harm” and with the implementation of owner mining and a single safety culture in 2011 we continue to work towards this goal.

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From June 2010 Heap Leach cut-offs were equivalent to those of the Lefroy Mill due to higher rehandling costs. Optimisation and capital upgrades of the heap leach operation were implemented in 2011 to reduce cost and improve throughput. A three-stage crushing circuit of 900 kw installed comminution power is currently used in a 24-hour operation to prepare -15 millimetre ores for agglomeration, stacking and leaching. The remaining pad capacity of the Heap Leach operation is 0.1 million tonnes, or half a month’s production at the current throughput rate. The flushing practice enables continual stacking at the Heap Leach facility and will be employed to treat the remainder of the heap leach ore supply.

Several small projects have been undertaken during 2011 at the heap leach crushing facility to increase throughput to 2.7 Mtpa. These include tramp metal removal, decoupling of the circuit (separating the crushing and agglomeration circuits into two processes that can operate independently) and a fully automatic stacker. A mobile oxide screen was recently introduced to the circuit to screen off oxides at 35 millimetres for direct feed into the agglomeration circuit, thereby bypassing the comminution phase.

Gold is stripped off the carbon, electrowon and calcined at the heap leach wet plant prior to shipment to the Lefroy gold room for smelting.

9

9. Mineral Resources and Mineral Reserves

Mineral ResourcesThe Mineral Resource statement for St Ives is summarised in the tables below. The impacts of year-on-year changes are discussed in the reconciliation section. The following factors apply to the Mineral Resources presented in this report:

¨ Mineral Resources are quoted at an appropriate in situ economic cut-off grade with tonnages and grades based on the relevant resource block models. The Mineral Resources also include estimates of any material below the cut-off grade required to be mined to extract the economic portion of the Mineral Resource;

Geology and evaluation models have been updated to reflect the latest available data sets. An integrated mine design and schedule plan based on current performance levels and takes

cognisance of the inherent risks associated with mining operations at St Ives.

Modifying factors ¨ The Measured and Indicated Mineral Resources are

inclusive of those Mineral Resources modified to produce Mineral Reserves;

¨ All Mineral Reserves are quoted in terms of run of mine (RoM) grades and tonnages as delivered to the metallurgical processing facilities and are therefore fully diluted;

¨ The Mineral Reserve statements include only Measured and Indicated Mineral Resources, modified to produce Mineral Reserves and contained in the LoM plan; and

¨ 100% attributable to St Ives Gold Mine; ¨ Surface sources are comprised of stockpiles and are

supported by adequate sampling, and are thus classified as Measured Mineral Resources; and

¨ All references to “tonnes” should be taken as being in metric units.

Mineral Resourceclassification

Tonnes (Mt) Grade (g/t) Gold (’000 oz)

Dec 2011

Dec 2010

June 2010

Dec 2011

Dec 2010

June 2010

Dec 2011

Dec 2010

June 2010

Open pit and underground

Measured 2.7 4.7 4.1 3.8 3.1 4.3 327 472 572

Indicated 43.2 41.4 48.0 2.6 2.9 2.5 3,591 3,898 3,847

Inferred 11.8 13.7 24.0 3.2 2.9 3.0 1,222 1,271 2,311

Total open pit and underground 57.7 59.7 76.1 2.8 2.9 2.7 5,140 5,641 6,729

Surface stockpiles

Measured 5.6 3.3 5.2 1.0 1.2 1.0 174 124 170

Total surface stockpiles 5.6 3.3 5.2 1.0 1.2 1.0 174 124 170

Grand total 63.3 63.0 81.3 2.6 2.8 2.6 5,314 5,765 6,899

Mineral Resourceby source


Dec 2011

Dec 2010

June 2010

Dec 2011

Dec 2010

June 2010

Dec 2011

Dec 2010

June 2010

Open pit 38.9 39.6 49.2 1.9 2.0 1.8 2,391 2,563 2,867

Underground 18.8 20.1 27.0 4.6 4.8 4.5 2,749 3,078 3,862

Stockpiles 5.6 3.3 5.2 1.0 1.2 1.0 174 124 170

Total 63.3 63.0 81.3 2.6 2.8 2.6 5,314 5,765 6,899

¨ Mineral Resources and Mineral Reserves undergo both internal and external audits during the year and any issues identified are rectified at the earliest opportunity – usually during the current reporting cycle, though it does sometimes occur that more comprehensive work requires more time for adequate completion.

For modifying parameters, see page 10.


Grade tonnage curves

Open pits

60

50

40

30

20

10

0

8

6

4

2

00.50.0 1.0 1.5 2.0 2.5 3.0 4.03.5

Cut-off grade (g/t)

— A

vera

ge g

rade

abo

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/t)

— T

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Underground

50

40

30

20

10

0

14

12

10

8

6

4

2

010 2 3 4 5 6 7 98

Cut-off grade (g/t)

— A

vera

ge g

rade

abo

ve c

ut-o

ff (g

/t)

— T

onne

s (m

illio

ns)

Mineral Resource parameters

Dec2010

Dec2011

Gold priceUS$/ozUS$:A$

A$/oz

1,1001.22

1,350

1,4501.07

1,550Cut-off for Heap Leach g/t 0.5 – 0.7 0.37 – 0.60Cut-off for mill feed g/t 0.7 – 2.6 0.67 – 0.94Cut-off for open pit (mill) g/t 0.5 – 0.8 0.37 – 0.77Cut-off for underground (mill) g/t 1.6 – 2.6 2.30 – 3.30Mineral Reserve parameters

Gold priceUS$/ozUS$:A$

A$/oz

1,0001.22

1,225

1,3001.07

1,400Cut-off for Heap Leach g/t 0.5 – 0.8 0.38 – 0.56Cut-off for mill feed open pit g/t 0.7 – 0.8 0.68 – 0.70Cut-off for mill feed u/g g/t 1.6 – 3.5 2.60 – 3.70Strip ratio waste:ore 6.2 6.2Dilution (open pits) % 13 – 30 6 – 50Mining recovery (open pits) % 90 – 93 90 – 99Mine Call Factor % 100 97Plant recovery factor % 83 – 94 83 – 94Heap Leach recovery factor % 55 – 75 55 – 75Processing capacity Mtpa 4.8 4.8Heap Leach capacity Mtpa 2.5 2.7Pit wall angles degrees 25 – 45 25 – 45

Mineral ReservesReported Mineral Reserves at St Ives were consistent at 2.8 Moz since December 2010, which indicates that depletion at 520 koz was matched by an underlying equivalent increase of 512 koz. The dominant contributors to Mineral Reserves at St Ives are the Athena, Hamlet, Bellerophon, Neptune and Cave Rocks projects. The Mineral Reserve statement for St Ives is summarised in the tables below and these following points apply:

¨ Estimates for St Ives include allowances for all relevant modifying factors; ¨ Mineral Reserves are reported in terms of tonnages, grades and contained gold delivered for processing; ¨ Surface sources are comprised of stockpiles. St Ives assumes that stockpiles are supported by adequate sampling, and are

thus classified as Proved Mineral Reserves; and ¨ All references to “tonnes” should be taken as being in metric units.

Mineral Reserveclassification


Dec 2011

Dec2010

June 2010

Dec 2011

Dec2010

June 2010

Dec 2011

Dec2010

June 2010

Open pit and underground

Proved 1.7 3.2 2.1 3.9 3.1 3.9 215 315 267

Probable 30.6 26.3 23.3 2.5 2.8 2.5 2,423 2,381 1,853

Total open pit and underground 32.3 29.5 25.4 2.5 2.8 2.6 2,639 2,696 2,120

Surface stockpiles

Proved 5.6 3.3 5.2 1.0 1.2 1.0 174 124 170

Total surface stockpiles 5.6 3.3 5.2 1.0 1.2 1.0 174 124 170

Grand total 37.9 32.7 30.6 2.3 2.7 2.3 2,813 2,820 2,290

11

Mineral Reserveclassified per mining area

Proved Probable Total Mineral Reserve

Tonnes (kt)

Grade (g/t)

Gold (koz)

Tonnes (kt)

Grade (g/t)

Gold (koz)

Tonnes (kt)

Grade (g/t)

Gold (koz)

Open pit

BLC land – – – 5,488 1.24 220 5,488 1.24 220

Condenser North – – – 181 2.19 13 181 2.19 13

Condenser South – – – 104 2.91 10 104 2.91 10

Foster – – – 965 1.92 59 965 1.92 59

Greater Intrepide 19 0.45 0.3 5,056 1.66 270 5,075 1.66 271

Greater Revenge 742 1.38 33 2,778 1.53 137 3,521 1.50 170

Greater Victory 18 2.46 1 3,638 1.39 162 3,656 1.39 164

Junction – – – 163 2.62 14 163 2.62 14

Kambalda Dome – – – 341 0.93 10 341 0.93 10

Neptune 45 2.05 3 3,515 2.63 297 3,560 2.62 300

Total open pit 824 1.42 38 22,228 1.67 1,192 23,052 1.66 1,230

Underground

Cave Rocks 96 4.52 14 419 4.36 59 516 4.39 73

Argo 478 6.18 95 245 5.28 42 723 5.87 137

Athena 306 6.70 66 1,906 5.57 342 2,211 5.73 407

Hamlet – – – 4,690 4.62 697 4,690 4.62 697

Greater Victory 35 2.64 3 1,111 2.58 92 1,146 2.58 95

Total underground 915 6.04 178 8,372 4.57 1,231 9,287 4.72 1,409

Surface

Total surface stockpiles 5,598 0.97 174 – – – 5 598 0.97 174

Grand total 7,337 1.65 390 30,600 2.46 2,423 37,936 2.31 2,813

Load

ing

ore

from

driv

e at

Bel

leis

le


Managed Mineral Reserve Sensitivity

Gol

d (M

oz)

2.4 2.62.8 3.0

3.1

3.5

Gold price (A$/oz)

(-10%) (-5%) (+5%) (+10%) (+25%)(Base)1,400

4.0

3.0

2.0

1.0

0

Change in Mineral Reserves December 2010 to December 2011

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.0

Res

ourc

em

odel

ling

Exc

lusi

ons

orIn

clus

ions

Eco

nom

ics

and

min

e de

sign

Oth

er

Dis

cove

ry

Pos

t dep

letio

n

Dec

embe

r 20

10

Dec

embe

r 20

11

2.8

0.5

0.70.1

0.3 2.8Gol

d (M

oz)

0.0

0.0

Factors that affected Mineral Resource reconciliation:

¨ Economic factors (higher costs);

¨ Depletion for the 12 months to 31 December 2011 of 520 koz, measured by processing feed; and

¨ New discovery (0.48 Moz) offset by economics and mine design (- 0.45 Moz)

7.0

6.0

5.0

4.0

3.0

2.0

1.0

0

Change in Mineral Resources December 2010 to December 2011

Gol

d (M

oz)

Dis

cove

ry

Oth

er

Dep

letio

n

Res

ourc

em

odel

ling

Incl

usio

ns o

rex

clus

ions

Eco

nom

ics

and

min

e de

sign

Dec

embe

r 20

10

Dec

embe

r 20

11

5.80.5

0.5

0.0 0.00.00.4 5.3

Mineral Reserve SensitivityThe following graph indicates the managed Mineral Reserve Sensitivity at -10%, -5%, Base, +5%, +10% and +25% to the gold price. To illustrate the impact of fluctuations in gold price and exchange rates on the current declaration, St Ives has generated sensitivities with respect to Mineral Reserves. These sensitivities (other than for the base case) are not supported by detailed plans and should only be considered on an indicative basis; specifically as such sensitivities assume 100% selectivity, without any operating cost increases.

Factors that affected Mineral Reserve reconciliation:

¨ Mined depletion for the period was measured by processing feed (-520 Moz);

¨ Discovery was dominated by Neptune, Cave Rocks, Britannia Footwall, Trinidad and nominal increases at Athena and Hamlet (0.68 Moz);

¨ Higher costs partially offset by gold price increases (- 0.31 Moz); and

¨ Resource modelling: Bellerophon (0.13 Moz).

Mineral Resources and Mineral Reserves reconciliation year-on-year

Sta

mpi

ng n

ewly

pou

red

gold

bar

s

13

10. Regulatory codes

SAMRECThis technical statement has been prepared in compliance with the South Africa Code for the Reporting of Exploration Results, Mineral Resources and Mineral Reserves (2007 SAMREC Code).

JSEThis technical statement has been prepared in compliance with the Listings Requirements of the JSE Limited, South Africa (JSE), specifically Section 12.

Sarbanes-Oxley ActThe Mineral Resources and Mineral Reserves are underpinned by an appropriate Mineral Resource management process and protocol to ensure adequate corporate governance in respect of the intent of the Sarbanes-Oxley Act.

EnvironmentalSt Ives has an environmental management team which is supported by specialists from the regional and corporate offices in Johannesburg and Perth. The systems, procedures, training etc. are at international leading practice levels.

Ope

n pi

t min

ing

activ

ities

Competent Persons

M Jolly: Manager Mineral Resources MSc (Geology), EDP Wits Business School, MAusIMM (304960). Mr Jolly has 31 years’ experience in the mining industry (three years at St Ives) and is responsible for the overall correctness, standard and compliance of this declaration.

J Woodcock: Exploration ManagerMSc (Geology), MAusIMM (305446). Mr Woodcock has 11 years’ experience in the mining industry (one year at St Ives) and is responsible for surface exploration and resource development drilling and the oversight of resource development geology models.

E Taylor: Acting Principal Resource Geologist BSc (Hons) Geological Engineering, MAusIMM (990584). Mr Taylor has 12 years’ mining industry experience (two years at St Ives), and is responsible for the gold resource estimation processes and models.

E Murray-Hayden: Acting Mine Geology ManagerMSc (Geology), Mrs Murray-Hayden has eight years’ experience in the mining industry (six years at St Ives) and is responsible for the mine geology functions at St Ives.

S Ellery: Resource Evaluation SuperintendentBSc (Hons), MSc Geology, Grad Dip Applied Finance and Investment (SIA), MAusIMM (110420). Mr Ellery has 21 years’ experience in the mining industry (19 years at St Ives) and is responsible for some aspects of economic evaluation at St Ives.

Technical reviews have been conducted by the Competent Persons as listed, who are full-time employees of Gold Fields Limited.

11. Competent Persons


Post Incumbent Qualifications Years Key responsibilities

General Manager Edward Lambourne

Associate Diploma EngineeringDiploma Business Management

25 Responsible for overall strategic direction, leadership and management

Operations Manager Craig Bradshaw B. Eng ( Honours) Mining Engineering 19 Full operational management

Manager Mineral Resources

Malcolm Jolly MSc (Geology), EDP (Wits)COM Cert. Rock Engineering

31 Exploration and mine geology Compilation of CPR

Commercial Manager Charl van Rensburg

B.Com 18 Financial management, reporting and compliance

Human Resources Manager

Petro Bekker B.Tech HR 29 Human resources, safety and health, emergency services

Processing Manager MetallurgyLefroy Mill

Scott Davies BSc (Hons) (Mineral Science)MAusIMM

12 Lefroy PlantMineral processing Metallurgy and tailings management.

Processing Manager MetallurgyHeap Leach

Warwick McKenzie

MSc Extractive MetallurgyMAusIMM

11 Mineral processing Metallurgy Heap leach plant

Engineering Manager Brian Cameron Mechanical Engineer CertificateNo 5025Diploma In Business Certificate No 00766

30 Engineering, logistics and infrastructure management

Technical Manager Robert Urie B. Eng (Hons) Mining Engineering. Dipl Applied Finance

18 Responsible for the mine planning and scheduling of underground mining operations.

Environment Manager Peter Bayliss BSc (Hons) (Applied Biology)MPhil (Environmental Sciences)

23 Environmental management

Safety Manager Edward Anderson B. App Science(Chem). FRACI, FAOQ 35 Occupational health and safety

12. Key technical staff

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The history of St Ives

1897: Gold discovered at Kambalda “Red Hill camp”.

1897 – 1907: Other gold-bearing locations, such as Victory, discovered with an estimated total production of 31 koz mostly from the Red Hill group of mines.

1919: New discovery led to construction of Ives Reward mine and small town in St Ives area.

1926: Ives Reward mine closed having produced 10 koz of gold, town abandoned.

1966:Iron-nickel sulphides discovered near the old Red Hill mine. WMC acquired ground and developed a mining and milling operation. From 1966 to 1996 the Region produced approximately 34.0 Mt of ore at an average grade of 3.1% nickel.

1970s: Increase in gold price led to a re-evaluation of the old gold prospects in the Kambalda area.

1980: Significant gold mineralisation identified beneath the Hunt nickel shoot.

1981: Discovery of the Victory-Defiance complex (Leviathan area). Gold production commences at St Ives using a 0.5 Mtpa treatment plant (later expanded to 1.2 Mtpa) located at the Kambalda Nickel Concentrator site.

1988: New 3.1 Mtpa CIL facility constructed 25 kilometres south of Kambalda at St Ives.

2001: 2.0 Mtpa heap leach facility commissioned. St Ives acquired by Gold Fields Limited.

2004: 4.8 Mtpa Lefroy mill constructed and fully commissioned in early 2005.

2006: Start of aggressive exploration programme with full field aircore drilling programme.

2007: Start-up and establishment of Cave Rocks and Belleisle underground mines.

2008: Initiation of mining new consolidated open pit: Leviathan.

2009: Discovery of new Athena-Hamlet deposit.

2010: Continued discovery growth of Hamlet deposit – plus 1 Moz Inferred Mineral Resource. Commencement of Athena mine. First ore intersected May 2010.

2011: Athena reached commercial level of production in September 2011. Hamlet development intersects first ore in October 2011 as part of a new mine development programme.

13. Brief history

Exp

lora

tion

drilli

ng o

n La

ke L

efro

y


Satellite image of the Athena/Hamlet area

St Ives Mineral Resource and Mineral Reserve Classification

EXPLORATIONRESULTS

MINERALRESERVES

MINERALRESOURCES

Reported as in situmineralisation estimates

Consideration of mining, metallurgical, economic, marketing, legal,environmental, social and governmental factors (the ‘modifying factors’)

63.3 Mt @ 2.6 g/t5.3 Moz

37.9 Mt @ 2.3 g/t2.8 Moz

30.6 Mt @ 2.5 g/t2.4 Moz

7.3 Mt @ 1.7 g/t0.4 Moz

11.8 Mt @ 3.2 g/t1.2 Moz

43.2 Mt @ 2.6 g/t3.6 Moz

8.3 Mt @ 1.9 g/t0.5 Moz

Reported as mineableproduction estimates

Incr

easi

ng le

vel o

f geo

scie

ntifi

c kn

owle

dge

and

confi

denc

e

MEASURED PROVED

PROBABLEINDICATED

INFERRED

19

Notes

Dec

line

port

al b

reak

aw

ay fo

r un

derg

roun

d m

inin

g

This Technical Short Form Report (“the Report”) contains information as at 31 December 2011 (“the Effective Date of this Report”). The statements and information set out in this Report speak only as of the Effective Date of this Report. Shareholders and other interested and affected parties are therefore urged to review all public disclosures made by Gold Fields after the Effective Date of this Report, as some of the information contained in the Report may have changed or have been updated. Gold Fields does not undertake any obligation to update publicly or release any revisions to statements and information set out in this Report to reflect events or circumstances after the Effective Date of this Report or to reflect the occurrence of unanticipated events, unless obliged to do so pursuant to law or regulation. In such event, Gold Fields does not undertake to refer back to any information contained in this Report.


“If we cannot mine safely, we will not mine”

Gold Fields Safety Value

Registered Office South Africa:150 Helen RoadSandownSandton, 2196 JohannesburgGautengPrivate Bag X30500Houghton, 2041 South Africa

Website: http://www.goldfields.co.za Telephone: +27 (0) 11 562 9700Facsimile: +27 (0) 11 562 9838

st ives gold mine · 2018-10-11 · gold fields: st ives gold mine – technical short form report...

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