Cerro Corona Mine - Gold Fields · Cerro Corona Mine operates one open pit operation and one copper-gold plant at elevations ranging from approximately 3,600 to 4,000 metres above

Cerro Corona MineTechnical Short Form Report31 December 2012

1. OverviewDuring 2012, Gold Fields Corona (BVI) Limited, a wholly owned

subsidiary of Gold Fields Limited, increased its economic interest

in Gold Fields La Cima S.A. (La Cima), from 98.5% to 98.5562%.

La Cima holds the Cerro Corona mine, which is located

approximately 600 kilometres north-northwest of Lima and

approximately 80 kilometres by road north of Cajamarca city.

The Cerro Corona mine is a large open pit mine situated in the

highest part of the Western Cordillera of the Andes Mountains in

northern Peru, approximately 1.5 kilometres west-northwest of

the village of Hualgayoc in the Department of Cajamarca.

Access to the Cerro Corona mine from Cajamarca is by means

of two roads, from Cajamarca to the Yanacocha mine and

from Yanacocha to the village of Hualgayoc. The deposit is

hosted by a sub-vertical, cylindrical-shaped diorite porphyry

(600 – 700 metres in diameter), emplaced in mid-Cretaceous

limestone, marls and siliciclastic rocks.

The Mine is expected to produce approximately 1.8 million

saleable ounces of gold and 394,000 saleable tonnes of copper

in concentrate over a 16 year Life of Mine (LoM). The plant has a

production capacity of 19,300 tonnes of ore per day, or about 6.7

million tonnes of ore per year.

Cerro Corona produces gold and copper by conventional open

pit mining methods and beneficiation of sulphide ores by the

extraction of a copper gold flotation concentrate, which is trucked

approximately 380 kilometres to the Peruvian port of Salaverry for

shipment to smelters in Asia and Europe.

This Technical Short Form Report provides brief information on

the mining and operational performance for the 12-month period

ended December 2012, and presents an updated Mineral

Resource and Mineral Reserve statement as at 31 December

2012.

All Mineral Resource and Mineral Reserve figures reported are

managed unless otherwise stated, and Mineral Resources

are inclusive of Mineral Reserves.

Geographic locationCerro Corona locality plan with mining concession magnified

Salient features

� MiMineneral Resource at 3.7 Moz gold and

1,302 Mlb copper.

�� Mineral Reserve at 2.8 Moz gold and

1,039 Mlb copper.

� A total of 170 koz of gold and 36.2 kt of

copper were produced in 2012.

�� InInInnInnn 2 22 22201010101012,2222 Cerro Corona received the

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1Gold Fields – Cerro Corona Mine – Technical Short Form Report 2012 �

Page head

Cover image:Panoramic view of the Cerro Corona open pit mine

Note: For abbreviations refer to page 27 and for glossary of

terms refer to page 28 – “Mineral Resources and Mineral

Reserves Overview 2012”.

��Cerro Corona countryside scenery

Contents

northern Peru.

Cerro Corona, which is currently the Cerro Corona, which is currently the

most profitable mine in Gold Fields, most profitable mine in Gold Fields, most profitable mine in Gold Fields,

produces gold and copper from a produces gold and copper from a

large open pit. It is located in the large open pit. It is located in the large open pit. It is located in the

highest part of the westernhighest part of the western

Cordillera of the Andes Mountains in Cordillera of the Andes Mountains in

northern Peru.northern Peru.

Geographic location IFC

1. Overview IFC

2. Asset fundamentals Page 2

3. Operating statistics Page 3

4. Geological setting and mineralisation Page 4

5. Mining Page 6

6. Projects Page 7

7. Mineral processing Page 8

8. Sustainable development Page 9

9. Mineral Resources and Mineral

Reserves Page 10

10. Competent Persons Page 13

11. Key technical staff Page 14

12. Brief history Page 17

2 � Gold Fields – Cerro Corona Mine – Technical Short Form Report 2012

2. Asset fundamentals

Prepared by Gold Fields Limited in compliance with the South African Code for the Reporting of Exploration

Results, Mineral Resources and Mineral Reserves (2007 SAMREC Code)

Effective date 31 December 2012

Source of information This Technical Statement is a summary of the December 2012 Cerro Corona Competent

Persons Report (CPR)

Personal inspection Personal inspection is conducted by the Competent Persons as listed, who are full-time

employees of Gold Fields Limited

Independent review Information reported in this declaration is as reviewed by internal consultants as at 31 December

2012. Cerro Corona has been informed that the review identified no material shortcomings in

any process by which the Mineral Resources and Mineral Reserves were evaluated

General location The Cerro Corona deposit, centered at longitude 78° 37’ 8” W and latitude 6° 45’ 36” S, is

located 1.5 km west-northwest of the village of Hualgayoc, some 80 km by road north of the

departmental capital of Cajamarca, and approximately 600 km north-northwest of the capital

city Lima

Climate No extreme climatic conditions are experienced that may affect mining operations

Licence status and holdings

The mining concessions owned by Cerro Corona cover an area of 2,761 hectares, while the

surface rights cover 1,264 hectares. Cerro Corona is owned by Gold Fields La Cima S.A.

(GFLC) which holds 98.5562 percent of the economic interest

Operational infrastructure

Cerro Corona Mine operates one open pit operation and one copper-gold plant at elevations

ranging from approximately 3,600 to 4,000 metres above mean sea level

Deposit type The Cerro Corona copper-gold deposit is typical of porphyry style mineralisation comprising

stockwork quartz-pyrite-marcasite-chalcopyrite ± bornite ± hematite ± magnetite veining,

hosted by intensely altered intrusive lithologies of diorite to dacitic composition

Life of Mine (LoM) It is estimated that the current Mineral Reserve will be depleted in 2028 (16 years)

Environmental/Health and Safety

In August 2012 the Integrated Safety, Occupational Health and Environment Management

System (SSYMA) was recertified in ISO 14001-OHSAS 18001.

An expansion for the Las Gordas waste storage facilities and the Cerro Corona Pit is under

consideration and permits for this expansion will be submitted during 2013, with all expectations

that they will be granted

Reporting codes Gold Fields reports its Mineral Resources and Mineral Reserves in accordance with the 2007

SAMREC Code, the South African Code for the Reporting of Mineral Asset Valuation (2009

SAMVAL Code) and other relevant international codes such as the United States Securities and

Exchange Commission (SEC) Industry Guide 7, the Joint Ore Reserves Committee (JORC 2012)

Code and the National Instrument (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 Sarbanes-Oxley Act

Cerro Corona open pit mine


3. Operating statistics

Historic performance UnitsDec

2012

Dec2011

Dec20101

June2010

June2009

Open pit mining

Total mined kt 14,006 12,591 6,164 13,614 9,938

– Waste mined kt 6,296 6,007 3,036 7,366 4,894

– Sulphide tonnes mined kt 7,710 6,584 3,128 6,248 5,044

Strip ratio (tonnes) waste:ore 0.8 0.9 1.0 1.2 1.0

Gold mined grade g/t 1.12 1.13 1.20 1.10 1.20

Copper mined grade % 0.60 0.69 0.70 0.80 0.80

Processing

Sulphide tonnes milled kt 6,513 6,593 3,102 6,141 4,547

Gold head grade g/t 1.24 1.22 1.29 1.14 1.24

Copper head grade % 0.68 0.74 0.79 0.85 0.78

Produced

Concentrate produced tonnes 180,851 190,007 92,390 194,201 118,848

Gold produced koz 170 161 80 139 105

Copper produced kt 36 39 20 41 24

Financials

Operating costUS$ million 171 157 77 135 86

US$/oz 501 411 388 343 394

Total cash cost US$/oz 492 442 395 348 369

Capital expenditure US$ million 94 69 31 86 122

Notional cash expenditure (NCE) US$/oz 775 592 544 561 926

General

Total Employees Costed (TEC) number 1,113 1,106 997 1,128 875

Mineral Reserves Mt 103.6 110.0 86.2 89.2 89.3

Mineral Reserves Au Head Grade g/t 0.8 0.9 1.0 1.0 1.0

Mineral Reserves Cu Head Grade % 0.5 0.5 0.5 0.5 0.5

Mineral Reserves – Au Moz 2.8 3.1 2.7 2.7 2.8

Mineral Reserves – Cu Mlb 1,039 1,126 965 976 988

Expected Life of Mine years 16 17 14 15 15

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.

Open pit mining Primary crushing Processing plant Tailings dam


4. Geological setting and mineralisation

The Cerro Corona mine is located in

northern Peru on the eastern slope of

the western mountain range of the

Andes. The copper-gold deposit is a

typical porphyry style of mineralisation

situated within the Hualgayoc mining

district in the northern part of the

Cajamarca province, a metallogenic

province hosting prolific epithermal,

porphyry and polymetallic style

mineralisation. The mining area is

characterised by moderate to

moderately steep mountainous terrain

with elevations ranging from

approximately 3,600 to 4,000 metres

above mean sea level.

The Cerro Corona copper-gold

porphyry is one of 14 known Tertiary

aged porphyry Cu-Au-Mo deposits and

19 epithermal gold-silver deposits

located in the Cajamarca metallogenic

province (CMP) of northern Peru. There

are two well-mineralised districts within the CMP.

The Yanacocha district in the south of the province is host

to the largest producing gold mine in South America, while

the Hualgayoc mining district in the north is one of the

oldest mining districts in Peru and is best known for its past

silver production and more recent base metal production.

This well-known district has been an important silver

producing area since Inca times, with more than 50 Moz

of silver and significant amounts of lead, zinc and copper

produced from vein and manto-type deposits since the

Spanish conquest in the 16th century. The Hualgayoc

mining town was established in 1771.

The regional structure is characterised by large open folds

of Cretaceous-aged sedimentary units, predominately

limestones, with axial planes striking approximately

The Cerro Corona copper-gold deposit is typical of porphyry style mineralisation comprising stockwork quartz-pyrite-marcasite-chalcopyrite ± bornite ± hematite ± magnetite veining, hosted by intensely altered intrusive lithologies of diorite to dacitic composition.

315° and steep south-west dips. Faulting is generally

restricted to normal and oblique slip faults with offsets of a

few metres to a few tens of metres.

Local geologyThe Cerro Corona copper-gold deposit is hosted by a

600 to 700 metre diameter subvertical, cylindrical-shaped

diorite porphyry emplaced in mid-Cretaceous limestone,

marls and siliciclastic rocks. Within the porphyry, the copper-

gold mineralisation is primarily associated with zones of

stockwork quartz veining conforming to classic porphyry-type

vein definition. The Cerro Corona porphyry is unusual in that

it carries a very high gold content compared to other

copper-gold deposits.

There are at least two phases of diorite placement, only

one of which is mineralised. The non-mineralised diorite is

generally regarded as the last event,

and is referred to as “barren core”.

Most recent geological modelling strongly

suggests that the Cerro Corona porphyry

probably comprises four or five satellite

stocks, the last two of which are barren.

Early mineralisation was accompanied

by moderate to strong potassic alteration,

which has been commonly overprinted

by late, semi-pervasive argillic alteration

and locally, by structurally controlled

phyllic alteration assemblages (quartz-

sericite-pyrite).

The intrusion has been emplaced at the

intersection of Andean parallel and

Andean-normal (transandean) structures,

which is a typical feature of the Cajamarca

metallogenic province. A dominant

northeast-southwest trending fault system,

Geology of the Cerro Corona mine area

LegendFaultPIT BoundaryProperty BoundaryQuarternary

Volcanic Rocks

Volcanic RhyoliticRhyolitic tuff

Intrusive Rocks

Las Gordas DioriteBellavista MonzodioritePorphyry granodioriticCerro Corona DioriteCore Barren NECore Barren SW

Sedimentary Rocks

Chulec FormationMujarrun FormationPariatambo FormationYumagual lowerYumagual middleYumagual upper

Regional geology mapCerro Corona Mine

Scale: 1/10,000 Date: December 2012Stratigraphy: J Jacay 2009Mapping & Interpretation by: A Uzategul OProjection: PSAD 56 Zone 17S

Cerro Corona PitT-di

Q

T-g-md

Las To

mastifault

Coym

olache Fault

Magaly Fault

Carita Fault

Falla Garita

Falla G

arita

Olga FaultMarie

la FaultPla

nta

Fault

Tizoc Fault

La Regal

ada

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t

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lvo

rin F

ault

Reg

al

ada

II Fa

ult Olga F

ault

Manuela Fault

Rita

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El Zorro Fault

Consulado FaultLa Jalca Fault

La

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ord

as F

au

lt

Falla 1

Fa

llala

s To

ma

sLas To

mas I F

au

lt

9250

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9252

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0 500 1 000 m

km-Ch

km-Yi

km-Pa

T-g-md

T-riT-gd

T-ri

T-di T-di T-ri

T-ri

T-diT-ri

T-tri

km-Pa

km-Ym

km-Ym

Km-Ys

Km-Mu

T-g-md

T-g-md

T-g-md

Km-Mu

Km-Ch

Km-Pa

T-gd

Di

DIESW

DIENEKm-Pa

Km-Yi

Q

Q

Q

T-gd

km-Yi

T-gdT-ri

760000 762000 764000

km-Yi

Lu

cia

Fu

alt

El Tin

go F

ault

T-ri

T-tri

T-di

T-g-md

T-gd

DI

Diene

Diew

Km-ch

Km-Mu

Km-Pa

Km-Yi

Km-Ym

Km-Ys

Q

Regional geology and metallogeny of the Cajamarca metallogenic province

ReferenceQuaternary

Miocene – VolcanicsOligo – Miocene intrusivesOligo – Miocene “Calipuy” volcanicsPaleocene sediments, continental

Upper cretaceous batholithCretaceous carbonates, sedimentsJurassic volcanicsTriassic – Jurassic carbonates

Paleozoic intrusivesPaleozoic metasediments

Precambrian metamorphicsMajor faultsChicama – YanacochaStructural corridorAlignment of porphyry depositsHigh sulfidation Au-AgDepositPorphyry Cu-AuDeposit

25 km

N

9300 N

9200 N

Yanacocha

PERU

Hualgayoc

Cerro Corona

Mina Congas

Cajamarca

700 E 800E


running through the intrusion, is referred to

as the Mariela Fault trend, which has an

important relationship in the distribution of

the mineralisation. There are three distinct

mineralised zones within the deposit.

These are identified as the Annulus zone,

the northern zone and the southern zone.

Each of these is treated separately in

geological and resource modelling.

In addition to the mineralised zones, the

deposit is characterised by several

domains conforming to the degree of

oxidation and weathering. Supergene

oxidation and leaching processes at Cerro

Corona have led to the development of a

weak to moderate copper enrichment

blanket. This allows for the subdivision of

the deposit from the surface downward,

into an oxide zone, a mixed oxide-

sulphide zone, a secondary enriched

(supergene) sulphide zone and a primary

(hypogene) sulphide zone.

Geological domains

Oxidation, weathering, leaching and

subsequent secondary enrichment has

led to the formation of four mineral

domains with distinctly different

metallurgical behaviour. These are

surrounded by barren intrusive and

Cretaceous sediments.

The upper-most domain is the oxide

domain. This is characterised by the

complete removal of copper

mineralisation through oxidation and

leaching. Gold mineralisation within the

oxide domain is characterised by some

improvement in grade and is free-milling

due to the complete breakdown of

primary sulphide minerals.

All of the ore beneath the oxide domain

makes up parts of the sulphide zone,

which is separated into three domains

on the basis of the degree of oxidation

and consequent change in sulphide

mineralogical composition. These three

domains, from top to bottom, are the

mixed domain, the supergene domain

and the hypogene domain. The

hypogene domain is the primary

sulphide zone and mainly comprises

chalcopyrite with average grades of

0.5% copper and 0.8 g/t gold. The

supergene domain is an enriched

copper blanket comprising chalcocite-

covellite-chalcopyrite with grades in the

range of 1% copper and 1 g/t gold.

Geology of the Cerro Corona intrusive


Volcanic Rocks

Volcanic RhyoliticRhyolitic tuff

Intrusive Rocks

Cerro Corona DioriteCore Barren NECore Barren SW

Sedimentary RocksChulec FormationPariatambo FormationYumagual lowerYumagual middleYumagual upper

Local geology mapCerro Corona Mine

Scale: 1/2,500 Date: December 2012Stratigraphy: J Jacay 2009Mapping & Interpretation by: A Uzategul OProjection: PSAD 56 Zone 17S

T-ri

T-tri

DI

Diene

Diew

Km-ch

Km-Pa

Km-Yi

Km-Ym

Km-Ys

Q

9252

000

9252

500

0 100 200 m

DIENE

DIESW

Km-Pa

Km-Ch

762500 763000 763500 764000

Km-Yi

Km-Ym

Km-Ys

Km-Yi

Q

Q

Di

Manuela Fault

La Gringa Fault

El Zorro Fault

Olga Gault

Diana Fault

Nancy F

ault

Ro

sa

Fault

Marie

lla Fault

Julia Fault

Violeta Fault

Ela F

ault

Olga Fault

Reg

alad

a II

Faul

t

La Reg

alad

a Fau

lt

Magaly Fault

La Jalca Fault

Po

lvo

rin F

au

lt

Alteration map at 3800 Bench level (currently mining)


Alteration

Weak potassic

Phyllic (silicification)

Moderate argillic-phyllic

Moderate argillic

Strong argillic

Moderate propylitic

Alteration map – Bench 3800Cerro Corona Mine

Scale: 1/2,000 Date: December 2012Mapping & Interpretation by: A Uzategul – E AyalaProjection: PSAD 56 Zone 17S

9252

000

925

2500

763000 763500

N

Olga F

ault

Mariela Fault

Carmen Fault

0 100 200 m

Plan view showing the geological domains at Bench 3800 (currently mining)

Geological Domains

Oxide

Mixed

Supergene

Hypogene

Barren Diorite

Cretaceous Sediments

Plan view RL 3800

0 50 100 150 200

+9252600

+9252500

+9252400

+925300

+

+925

+925200

+9251900

+9251800

Elev (Z)

+763000

+763100

+763200

+763300

+763

+763500

+763600

+763700

Ea

st

(X)


5. Mining

Cerro Corona Mine operates one open pit operation at elevations ranging from approximately

3,600 to 4,000 metres above mean sea level.

The Cerro Corona deposit is mined by conventional surface

mining methods. The final surface mine area is expected to

cover some 900 by 1,000 metres. The mining operation will

extend from the crest of the original Cerro Corona hill, which

peaked at 3,964 mRL, to a final depth at around 3,510 mRL.

Cerro Corona is mined via open pit methodology using

conventional drill and blast with a truck and front-end loader

fleet. Load and haul is carried out by 90 tonne dump trucks

and 11.3 cubic metre front end loaders. Mining benches are

all 10 metres high. At this stage it is assumed that all of the

material requires drilling and blasting (with varying powder

factors) utilising 200 millimetre holes.

Mine planning and schedulingCerro Corona’s LoM plan is based on detailed geological and

resource models. The LoM plan is established from detailed

short-term and long-term mining design and schedules using

specialised Xpac© software and a resource estimation model

termed the localised multivariate uniform conditioning

model (LMUC).

Key input parameters are ratified at the beginning of the

planning cycle and a compliant Mineral Resource statement

is then produced. The planning process starts after the

construction of the resource model and incorporates the

following considerations:

�� corporate decisions on macro-economic parameters;

�� development of a broad planning strategy, identifying key

mining and processing constraints;

�� development of comprehensive operating costs for mining,

processing, administration and selling;

�� modelling of the strategic, geological, geotechnical,

metallurgical, environmental and economic parameters for

application of the Lerchs Grossman algorithm. A broad

economic sequence and an optimum ultimate economic

pit shell is subsequently developed;

Exploration and

resource definition

drilling

A deep diamond drill campaign

was conducted during 2012 to

test mineralisation at depth

(>1,000 metres) beneath the

Resource pit. In total

6,713 metres of core drilling

were completed. Results are

pending and geological

interpretation is under way.

Exploration drilling and expenditure:

31 December 2012 31 December 2011

Operation

Metres

drilled

US$

(million)

Metresdrilled

US$(million)

Cerro Corona Mine 6,713 2.789 9,449 2.824

Exclusive of grade control drilling except where it is included in the capital budget.

West-east section through the Cerro Corona intrusion showing interpreted geological domains


�� development of a pit design and push-backs applying

mine design parameters; and

�� the reserve model contained within the pit design is

scheduled with consideration of impacting factors such as

the following:

– economic valuation using a NSR cut-off for each

measured or indicated block considered for processing;

– optimum practical economic sequence as generally

defined by the push-backs;

– structural material required for earth structures;

– constraints related to the deposition of tailings

and overburden material; and

– alteration and clay content.

Open pit optimisations are built using Whittle 4X© multi-

element standard mine design software on the LMUC

resource model. Multiple-case scenarios are run using

varying gold and copper prices, processing costs, mill

recovery values and inclusion/exclusion of Inferred material to

ensure that the optimal pit is selected. However, no Inferred

Mineral Resource material is included in the Mineral Reserves.

The work undertaken includes:

�� geotechnical review and pit wall angle recommendation;

�� cost review;

�� pit optimisation; and

�� sensitivity analysis.

Partial view of Cerro Corona open pit mine

6. Projects

In 2012 the pre-feasibility study for processing ~7 million tonnes of oxide ore by the heap leaching technique was completed.

These oxide ores, much of which are already stored in surface stockpiles, are estimated to contain approximately

300,000 ounces of gold. The feasibility study is expected to be completed by Q2 2013.

The feasibility study for increasing the throughput of the sulphide process plant for Cerro Corona is currently underway. The

feasibility study is expected to be completed by Q2 2013.

The current sulphide plant is being optimised with several small to medium projects to

increase production throughput and to improve recoveries. These projects are scheduled for

completion by H1 2013.

View of Cerro Corona tailings storage facility


Various ore types from the mine are stockpiled on the RoM

pad and fed to the crushing plant in appropriate blends by a

front-end loader. The crushing plant comprises two mineral

sizers in parallel, one of which is a standby unit. These

facilitate crushing of soft, wet ore with clay components.

The crusher feed design also makes provision for direct

tipping of ore from the mine if necessary.

Crushed product is conveyed to a two-stage grinding circuit

consisting of a semi-autogenous grinding (SAG) mill and a

ball mill, in closed circuit with cyclones for classification.

Cyclone overflow represents the final milled product and

feeds the flotation plant which consists of three sections.

The rougher flotation produces a bulk concentrate, which is

then reground and sent to cleaner flotation (two stages). The

tails go to scavenger flotation while the concentrate with a

grade over 20% of copper goes to the next process.

The final concentrate is thickened and filtered before being

stockpiled for final shipment to Salaverry port. The thickened

rougher flotation tails and the tails from the cleaner-scavenger

flotation are sent by gravity to the tailings storage facility. Metal

recoveries have been modelled as grade-dependent non-

linear relationships, for both copper and gold. Some other

factors such as clay content, high Fe/Cu grade ratio and rock

acidity, appear to be influencing the metallurgical behaviour.

Mineral Reserves are constrained by the size of the tailings

storage facility. At December 2012, the remaining storage

capacity of tailing dam is 103.6 Mt. The capital costs

estimated for LoM construction work amount to

US$383 million made up predominantly of wall raising and

seepage control measure/blankets.

During 2012, the following initiatives were undertaken to

optimise metallurgical recovery:

�� Detailed mineralogical description: developed in detail for

the mining polygons planned as plant feed, which

facilitates the identification of the correct reagent recipe for

the different ore types.

�� Geo-Metallurgical Units (UGM): five Geo-Metallurgical

Units were defined for the Cerro Corona ore body in

partnership with an external consultant.

�� Work Index Comparative: polygons from different areas of

the pit were studied by an external lab to determine the

work index variation. This information will be used by the

Geo-Metallurgical team to improve plant performance,

adding a more reliable hardness parameter to the blending

process.

�� Variability test works: to determine the heterogeneity of the

different polygons.

�� An expert system was installed in the flotation area.

�� A gravimetric concentrator for the rougher concentrate.

�� Froth force rotors were installed in OK 160 cells.

�� New reagents were tested.

�� The ph was modified to 9 in the rougher flotation.

The processing plant at Cerro Corona includes the typical equipment for a copper flotation

plant. Design capacity planned to treat 775 (current 800) tonne/hour at 91.3% (current 95%)

availability to reach an annual treated tonnage of 6.7 million ore tonnes.

7. Mineral processing

View of the processing plant


8. Sustainable development8. Sustainable development8. Sustainable development

In 2012, Cerro Corona received the prestigious John T. Ryan

award in the Open Pit Mining Category. This award is based

on Safety and Occupational Health performance over a

three-year period. In late 2012, GFLC was recognised from

among 80 companies in Peru for its commitment to

sustainable development. It received the CEMEFI and Peru

2021 ESR (Empresa Socialmente Responsable) Award for

social responsibility in October, placing it among the top

44 companies in the country in terms of corporate

responsibility practices. The remote location of the operation

means that local communities are particularly reliant on Gold

Fields’ support for socio-economic development and the

provision of basic infrastructure.

In line with a well-entrenched sustainable development and

community engagement policy, the operation has invested

heavily in local community development and responsible

environmental management since the exploration stage

at Cerro Corona.

In 2012 the Mine continued to invest in the productive rural

programme, sowing 269 hectares of improved pastures to

increase dairy farming production and income. This

programme also focuses on improving the genetic quality of

livestock through artificial insemination. In another intervention,

100 hectares of pine trees were planted in partnership with

local communities.

A school was built in the Sacsapuquio community, and

construction was started on a drinking water system in the

Pilancones community. A Kindergarten school was

constructed for children in the Tingo community.

Sprinkler system in Pilancones community

In August 2012 the Integrated Safety, Occupational Health and Environment Management

System (SSYMA) was recertified in ISO 14001-OHSAS 18001. No fatalities or lost time

injuries were recorded during 2012. In total 8.0 million man work hours without any lost time

injuries (LTI) were accumulated since the previous injury.

School in Sacsapuquio community built by Gold Fields

Improved pastures in EI Tingo community

Safety statistics

Class Units Dec 2012 Dec 2011 Dec 20101 June 2010 June 2009

Fatalities number – – – – –

Fatality rate per mmwh – – – – –

LTIFR2 per mmwh – 0.18 – 0.16 0.32

1For six months to December 2010.2Lost Time Injury Frequency Rate (per million man work hours).

The strategy of recruiting local labour and utilising local

suppliers is bearing fruit. In 2012, sixty local suppliers were

contracted and 519 workers were in the employ of the Mine

from the town of Hualgayoc.

A sixth amendment to the EIA concerning extensions to the

pit, new quarries and topsoil dumps, was submitted early in

the year and approval is anticipated in April 2013. Once this

approval has been received, the eighth amendment will be

submitted, which will include further extensions to the pit, an

increase in the elevations of the TSF, the Tomas reservoir and

possible heap leach and sulphide projects. The seventh

amendment, which was submitted in September 2012, was

linked to water quality, particularly the treatment of the TSF

pond water for discharged excess waste.


9. Mineral Resources and Mineral Reserves

The Mineral Resources and Mineral Reserves are reported from the LMUC model at a Net Smelter Return (NSR) cut-off

of US$18.46/t, and constrained within an optimised Whittle pit shell, based on the same economic parameters as the

NSR calculation. The Mineral Resources are constrained by the capacity of the waste storage facility of 144 million tonnes.

The Mineral Reserves are constrained by the total capacity of the upgraded tailing storage facility of 130 million tonnes

(103.6 million tonnes post December 2012).

Modifying factors�� Mineral Resources and Mineral Reserves are quoted at an

appropriate economic NSR* cut-off, with costs and

tonnages and grades based on the resource block model.

They also include estimates of any material below the NSR

cut-off that needs to be mined in order to extract the

complete pay portion of the Resource;

�� Mineral Resources and Mineral Reserves are quoted as at

31 December 2012;

�� Unless otherwise stated, all Mineral Resources and Mineral

Reserves are quoted as 100% and are not attributable

with respect to ownership;

�� All Mineral Reserves are quoted in terms of RoM grades

and tonnages, as delivered to the metallurgical processing

facility;

* Net smelter return (NSR) is defined as the return from sales of concentrates, expressed in US$/t, i.e.: NSR = (Au price – Au selling cost)

x Au grade x Au recovery + (Cu price – Cu selling cost) x Cu grade x Cu recovery.

Mineral Resource classification

GoldClassification

Tonnes (Mt) Gold grade (g/t) Gold (koz)

Dec

2012

Dec 2011

Dec 2010

Dec

2012

Dec 2011

Dec 2010

Dec

2012

Dec 2011

Dec 2010

Open pit

Measured 90.3 98.0 44.1 0.84 0.86 1.00 2,437 2,717 1,411

Indicated 45.9 44.9 100.0 0.61 0.61 0.73 893 882 2,331

Inferred 1.1 0.8 2.2 0.36 0.34 0.54 12 9 38

Total open pit 137.3 143.8 146.3 0.76 0.78 0.80 3,342 3,608 3,780

Surface stockpiles

Measured 8.9 7.9 7.8 1.26 1.33 1.34 360 339 335

Total surface stockpiles 8.9 7.9 7.8 1.26 1.33 1.34 360 339 335

Grand total 146.2 151.7 154.1 0.79 0.81 0.83 3,702 3,946 4,115

CopperClassification

Tonnes (Mt)1 Copper grade (%) Copper (Mlb)

Dec

2012

Dec 2011

Dec 2010

Dec

2012

Dec 2011

Dec 2010

Dec

2012

Dec 2011

Dec 2010

Open pit

Measured 90.2 97.5 44.0 0.45 0.46 0.55 886 981 530

Indicated 45.5 44.5 99.8 0.39 0.39 0.41 389 387 903

Inferred 1.0 0.8 2.1 0.35 0.33 0.39 8 6 18

Total open pit 136.7 142.9 145.9 0.43 0.44 0.45 1,282 1,373 1,451

Surface stockpiles

Measured 2.1 1.2 1.2 0.42 0.50 0.49 20 13 13

Total surface stockpiles 2.1 1.2 1.2 0.42 0.50 0.49 20 13 13

Grand total 138.8 144.1 147.1 0.43 0.44 0.45 1,302 1,386 1,4641 These tonnes are repeated in the gold statement, but exclude the gold only bearing oxide tonnes.

�� Due to TSF constraints, ore stockpiles were excluded from

Mineral Reserves. Strategic analysis indicates that

processing fresh material will provide better metallurgical

recoveries.

�� Mineral Reserve statements include only Measured and

Indicated Mineral Resources, modified to produce Mineral

Reserves as contained in the LoM plan; and

�� Mineral Resources and Mineral Reserves undergo internal

audits during the year and any issues identified are

rectified at the earliest opportunity – usually during the

current reporting cycle.

Mineral Resources are reported as in situ within pit shells and are inclusive of those Mineral

Resources which have been modified to produce Mineral Reserves. The Measured, Indicated

and Inferred oxide and sulphide Mineral Resource estimate has been calculated within the

diorite intrusion above 3,300 mRL.


Mineral Resource parameters Units

Dec

2012

Dec2011

Gold price US$/oz 1,650 1,450

Copper price US$/lb 3.90 3.90

NSR cut-off for mill feed US$/t 18.46 18.01

Cut-off for oxide ore g/t 0.40 0.40

Mineral Reserve parameters Units

Dec

2012

Dec2011

Gold price US$/oz 1,500 1,300

Copper price US$/lb 3.50 3.50

NSR cut-off for mill feed US$/t 18.46 18.01

Strip ratio waste:ore 0.81 0.75

Dilution % 0 0

MCF % 100 100

Mining recovery factor % 100 100

Plant recovery factor (Au) – Mixed % 51 51

Plant recovery factor (Cu) – Mixed % 65 61

Plant recovery factor (Au) – Supergene % 66 67

Plant recovery factor (Cu) – Supergene % 85 82

Plant recovery factor (Au) – Hypogene % 70 70

Plant recovery factor (Cu) – Hypogene % 88 88

Processing capacity Mtpa 6.7 6.6

Grade tonnage curves

Sulphide Mineral Resources

To

nnes (m

illio

ns)

Avera

ge C

u g

rad

e a

bove c

ut-

off (%

)

Avera

ge A

u g

rad

e a

bove c

ut-

off (g/t

)

0 5 10 15 20 25

Cut-off net smelter return ($/t)

200

160

120

80

40

0

1.0

0.8

0.6

0.4

0.2

0

Oxide Mineral Resources

To

nnes (m

illio

ns)

Avera

ge A

u g

rad

e a

bove c

ut-

off (g/t

)

0 0.2 0.4 0.6 0.8 1.0 1.2 1.4

Cut-off grade Au (g/t)

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

0

2.0

1.5

1.0

0.5

0

Mineral Reserve classification

Gold Classification

Tonnes (Mt) Gold grade (g/t) Gold (koz)

Dec

2012

Dec 2011

Dec 2010

Dec

2012

Dec 2011

Dec 2010

Dec

2012

Dec 2011

Dec 2010

Open pit

Proved 77.4 85.3 41.0 0.89 0.92 1.03 2,212 2,512 1,357

Probable 26.3 23.5 44.1 0.67 0.68 0.89 563 513 1,267

Total open pit 103.6 108.8 85.1 0.83 0.86 0.96 2,775 3,025 2,623

Surface stockpiles

Proved – 1.2 1.2 – 1.24 1.26 – 47 48

Total surface stockpiles – 1.2 1.2 – 1.24 1.26 – 47 48

Grand total 103.6 110.0 86.3 0.83 0.87 0.96 2,775 3,072 2,672

Copper Classification

Tonnes (Mt) Copper grade (g/t) Copper (Mlb)

Dec

2012

Dec 2011

Dec 2010

Dec

2012

Dec 2011

Dec 2010

Dec

2012

Dec 2011

Dec 2010

Open pit

Proved 77.4 85.3 41.0 0.47 0.48 0.56 798 897 507

Probable 26.3 23.5 44.1 0.42 0.42 0.46 240 215 444

Total open pit 103.6 108.8 85.1 0.45 0.46 0.51 1,039 1,112 951

Surface stockpiles

Proved – 1.2 1.2 – 0.50 0.50 – 13 13

Total surface stockpiles – 1.2 1.2 – 0.50 0.50 – 13 13

Grand total 103.6 110.0 86.3 0.45 0.46 0.51 1,039 1,126 965


Factors that affected Mineral Resource reconciliation

�� Decrease resulting from mining depletion

�� An increase in gold price

�� An updated resource model

�� An increase in the NSR cut-off as a result of an increase

in overall cost and sustaining capital

Go

ld (M

oz)

0.01

0.02

0.02 3.700.07 0.02

0.00.33

3.95

Change in gold Mineral ResourcesDecember 2011 to December 2012

Dis

co

very

Decem

ber

20

11

Min

ed

dep

letio

n

Reso

urc

e

mo

delling

Meta

l p

rice

Co

sts

Oth

er

Exclu

sio

ns

Decem

ber

20

12

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0

Co

pp

er

(Mlb

)

4

10

7 1 30237 9

0.0123

1 386

Change in copper Mineral ResourcesDecember 2011 to December 2012

Dis

co

very

Decem

ber

20

11

Min

ed

dep

letio

n

Reso

urc

e

mo

delling

Meta

l p

rice

Co

sts

Oth

er

Exclu

sio

ns

Decem

ber

20

12

1 600

1 400

1 200

1 000

800

600

400

200

0

Factors that affected Mineral Reserve reconciliation

�� Decrease resulting from mining depletion

�� An increase in gold price

�� New geological and resource model

Go

ld (M

oz)

0.01

0.02 0.052.780.08 0.02

0.00.32

3.07

Change in gold Mineral ReservesDecember 2011 to December 2012

Dis

co

very

Decem

ber

20

11

Min

ed

dep

letio

n

Reso

urc

e

mo

delling

Meta

l p

rice

Co

sts

Oth

er

Exclu

sio

ns

Decem

ber

20

12

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0

Co

pp

er

(Mlb

)

3

5

131 03939 7

0.0121

1 126

Change in copper Mineral ReservesDecember 2011 to December 2012D

isco

very

Decem

ber

20

11

Min

ed

dep

letio

n

Reso

urc

e

mo

delling

Meta

l p

rice

Co

sts

Oth

er

Exclu

sio

ns

Decem

ber

20

12

1 200

1 000

800

600

400

200

0

Mineral Reserve sensitivityThe Mineral Reserve sensitivity is influenced by increased commodity prices, but is constrained by the size of the tailings storage

facility (130 Mt).

The sensitivities are not based on detailed depletion schedules and should be considered on a relative and indicative basis only.

Managed Mineral Reserve sensitivity – Gold

Go

ld (M

oz)

2.82.82.82.82.82.8

(-10%) (-5%) (Base)1,500

(+5%)

Gold price (US$/oz)

(+10%) (+25%)

3.0

2.0

1.0

0

Managed Mineral Reserve sensitivity – Copper

Co

per

(Mlb

)

1,0391,0391,0391,0391,0391,039

(-10%) (-5%) (Base)3.5

(+5%)

Copper price (US$/lb)

(+10%) (+25%)

1,200

1,000

800

600

400

200

0

Mineral Resources and Mineral Reserves reconciliation year-on-year

Note: Cerro Corona is still tonnage-constrained due to the capacity of its tailings facility. Adoption of possible TSF expansion opportunities will provide the mine with

future upside potential.


10. Competent Persons

Competent Persons

Eddie Garcia: Mineral Resources Manager

Mining Engineering, MBA, SAIMM (704963), SME (4028357), CIP (109603), Pontificia Universidad Católica del Perú. Mr

Garcia has 15 years’ experience in mining engineering and three years in business planning. Mr Garcia is the lead Competent

Person responsible for the Mineral Resources and Mineral Reserves at Cerro Corona and compilation of the CPR.

Paul Gómez: Geology and Exploration Manager

Geological Engineering, Universidad Nacional San Antonio Abad del Cusco CIP (130253), Diplomate in Geometallurgy

Pontificia Universidad Católica del Perú. Certified in applied geostatistics by the University of Alberta. Mr Gómez has over

14 years’ experience in consulting, exploration, mining and resource modelling on world-class operations. Currently, he is

responsible for the Geology Department and Exploration at Cerro Corona Mine.

Hugo Solis: Chief Engineer

Mining Engineering, CIP (77973), Universidad Nacional Mayor de San Marcos. Mr Solis has 17 years’ experience in surface

and underground mining operations. Mr Solis has completed his MBA studies at Centrum Católica.

Hugo Rios: Senior Resource Modeller

Geological Engineering, Universidad Nacional de Ingeniería, MBA Centrum Católica, MAusIMM (311727), CIP (92165), SEG

(672559). Certified in applied geostatistics by the University of Alberta. Mr Rios has over 11 years’ experience in exploration,

mining and resource modelling. Currently, he is responsible for the Resource Department at Cerro Corona Mine.

Angel Uzategui: Senior Mine Geologist

Geological Engineering, CIP (12337), Universidad Nacional San Agustín. Mr Uzategui has over 19 years’ experience in surface

and underground mining operations and exploration, he is responsible for the Grade Control Department and Structural and

Geological interpretation at Cerro Corona Mine.

Internal technical reviews have been conducted by the Competent Persons as listed, who

are full-time employees of Gold Fields Limited.

Copper-gold flotation concentrate being loaded for shipment


12. Key technical staff

Post Incumbent Qualifications Years Key responsibilities

General Manager Manuel Diaz Metallurgical Engineering 27 Responsible for the overall strategic

direction, leadership and

management

Consulting

Geologist

Julian Misiewicz MSc Geology

SEG (541613)

34 Standard and compliance of this

declaration and member of the Task

Team that support Independent

Geotechnical at Tailings Review

Board (IGTRB)

Consulting Mining

Engineer

Donald

Ross-Watt

MSc Mineral Economics

SAIMM (19412), ECSA (82190)

40 Standard and compliance of this

declaration and member of the Task

Team that Support IGTRB

Strategic Planning

Manager

Alberto

Cardenas

Civil Engineering, CIP (62693),MBA 18 Strategic direction and member of

the Task Team that support IGTRB

Operations

Manager

Gonzalo

Eyzaguirre

Mine Engineering, CIP (70978),

MBA

18 Mine operations process plant and

tailing construction

Chief Financial

Officer

Rodolfo Michels BS in Business Administration 44 Financial reporting and compliance

Process Manager Ronald Diaz Metallurgical Engineering 17 Mineral processing and metallurgy

Technical Manager Sergio Cruz Metallurgical Engineering

CIP (46193)

28 Geometallurgical Management and

Process Technical Support

Safety and Health

Manager

Tomas

Chaparro

Mining Engineering CIP (95784) 15 Safety and Health Management

Environmental

Manager

Luis Alberto

Sanchez

MSc Environmental Services

Mechanical Engineering, CIP

(53422)

29 Environmental management

Cerro Corona open pit mining operations

Gold Fields LimitedCerro Corona Mine

Plan showing mine infrastructure as at 31 December 2012500 0 500 1 000

MetresProvisional South American datum 56

Page width 208 mm Page width 205 mm

Project Boundary . . . . . . . .Open pit . . . . . . . . . . . . . . .Tailings Dam . . . . . . . . . . . .Waste Dump . . . . . . . . . . . .Quarry . . . . . . . . . . . . . . . . .Top Soil Dump . . . . . . . . . .Blankets . . . . . . . . . . . . . . .

Reference

Oxide Stockpile . . . . . . . . .Office . . . . . . . . . . . . . . . . .Rivers . . . . . . . . . . . . . . . . .Roads . . . . . . . . . . . . . . . . .Powerline . . . . . . . . . . . . . .

Low Volume Underflow (LVU)

12. Brief history

The history of Cerro Corona

1979: Exploration by BRGM identified porphyry-style mineralisation in the Cerro Corona area.

1984 – 2003: Mina Carolina intermittently exploited lead-zinc-silver mantos and veins in Hualgayoc district.

1992 – 1993: Sampling by Gubbins Group identified gold mineralisation in leached cap of Cerro Corona deposit. Cu Au

porphyry mineralisation discovered through drilling of nine diamond core holes and completion of

exploration adit into mineralised zone.

1994 – 1996: Cerro Corona optioned by Barrick. 140 reverse circulation drill holes totalling 9,476 metres and

118 diamond core holes totalling 35,694 metres completed in Cerro Corona deposit area. Draft feasibility

study completed by Kilborn indicating Mineral Reserves of 6.85 Mt of oxide ore at 1.34 g/t Au and 84 Mt

of sulphide ore at 1.02 g/t Au and 0.58% Cu.

1997 – 1998: Cerro Corona optioned by RGC Limited. Six diamond core holes totalling 2,760 metres completed.

Preliminary feasibility study completed by Fluor in 1998 estimated Mineral Reserves at 6.98 Mt of oxide ore

at approximately 1.3 g/t Au and 133 Mt of sulphide ore at 0.91 g/t Au and 0.52% Cu.

2000 – 2001: Minproc draft feasibility study estimated sulphide Mineral Reserves at 65.2 Mt at 1.14 g/t Au and 0.61%

Cu. However, this was followed immediately by a further study, which indicated a Mineral Reserve of 95 Mt

that was used in the due diligence.

2003: Gold Fields, through a subsidiary, signed a definitive agreement with Sociedad Minera Corona S.A. for the

purchase of the Cerro Corona deposit and adjoining mining concessions.

2004 – 2005: Gold Fields completed surface land acquisition, project engineering and design work, environmental

impact assessment, pit dewatering investigations, remapping of surface geology, relogging of prior drill

core, check assaying investigations and updated Mineral Resource and Mineral Reserve estimates.

2006: Environmental impact assessment approved on 2 December 2005. Purchase transaction for the Cerro

Corona Project completed in January 2006. Mine construction commenced in May 2006.

2007: Las Gordas tailing dam construction commenced in May 2007. Rhyolite quarry commenced mining.

2008: Cerro Corona moved into production in August 2008 when the process plant started to operate.

2009: 139 koz of gold, 41 k/tonne of copper and 394 koz of equivalent oz were produced between July 2009

and June 2010 in Cerro Corona.

2010: A 5,916-metre in-fill drilling programme was conducted during the first half of the year.

2011: A 9,449-metre in-fill drilling programme was completed to improve the resource model.

Gold Fields Corona (BVI) Limited a wholly owned subsidiary of Gold Fields Limited increased its economic

interest in Gold Fields La Cima S.A. from 80.7% to 98.5%.

2012: A 6,713-metre diamond drilling programme with deep holes (>1,00 metres) was completed to investigate

mineralisation beneath resources pit. Analytical results and geological interpretation are pending. In 2012

the economic interest increased to 98.5562%.

View of tailings storage facility


Cerro Corona 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”)

Gold 146.2 Mt @ 0.79 g/t 3.7 Moz Copper 138.8 Mt @ 0.43% 1,302 Mlbs

Gold 103.6 Mt @ 0.83 g/t 2.8 Moz Copper 103.6 Mt @ 0.45% 1,039 Mlbs

Gold 26.3 Mt @ 0.67 g/t 0.56 Moz Copper 26.3 Mt @ 0.4% 240 Mlbs





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

3D model of the Cerro Corona ore body

� Barren diorite

��Mineralised core


This Technical Short Form Report (the Report) contains information as at 31 December 2012 (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 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.

Notes

BASTION GRAPHICS

Panoramic view of Cerro Corona open pit mine

Registered Office South Africa:

150 Helen RoadSandownSandton, 2196JohannesburgGauteng

Private Bag X30500Houghton, 2041South Africa

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

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

Gold Fields Safety Value

Documents

Cerro Corona Mine - Gold Fields · Cerro Corona Mine operates one open pit operation and one copper-gold plant at elevations ranging from approximately 3,600 to 4,000 metres above