Cerro Corona Mine
Technical Short Form Report
The Cerro Corona Mine in the Gold Fields Limited South America Region, is located
40 km north of the Yanacocha mine, and 80 km by road north of the departmental capital
of Cajamarca in northern Peru. The deposit is hosted by a sub-vertical, cylindrical shaped
diorite porphyry (600 – 700 m in diameter), emplaced in mid-Cretaceous limestone, marls
and siliclastic rocks.
This Technical Short Form Report provides brief information on the mining and operational
performance achieved during the first 10 months of operations and also presents an updated
Mineral Resource and Mineral Reserve statement, as at 30 June 2009. 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 km to the Peruvian Port of Salaverry for shipment to smelters in Asia
and Europe
The Mine is expected to produce approximately 2.1 Moz of gold and 407 kt of copper in
concentrate over a 15 year Life of Mine. At the declared commodity prices, the estimated
copper and gold production is equal to a total of 4.5 million ounces gold equivalents
(Moz Au Eq). The Metallurgical Process Plant has a treatment capacity of 18,000 tons of
ore per day, or approximately 6.2 million tons of ore per year. LoM average total cash cost
(exclusive of capital costs and taxes) is projected at US$358/oz AuEq.
All Mineral Resource and Mineral Reserve figures reported are managed unless otherwise
stated and Mineral Resources are inclusive of Mineral Reserves.
Salient Features
- Ore processing started in August 2008 and full production was reached in
December 2008.
- A total of 105 koz of gold and 23,947 t of copper were produced in the
first 10 months of operation.
- Mineral Resource at 8.1 Moz (gold equivalent).
- Mineral Reserve at 5.5 Moz (gold equivalent).
- The current Life of Mine extends to 2024 (15 years).
- Anchor point for growth in the Region.
Gold Fields Limited signed a definitive agreement in December 2003 to purchase an 80.7%
economic and 92% voting interest in the Cerro Corona Project from Sociedad Minera Corona S.A.,
or SMC, a Peruvian family-owned company. The agreement called for a corporate reorganisation
whereby the assets of the Cerro Corona Project were transferred to a Peruvian company called
Gold Fields La Cima S.A. (formerly known as Sociedad Minera La Cima S.A.) in July 2004.
The environmental impact assessment (EIA) for the project was submitted to the Peruvian Ministry
of Energy and Mines, or MEM, in May 2005. The EIA was approved following a process of public
consultation and comment, on 2 December 2005. Gold Fields Limited subsequently completed
the purchase of a 92% voting interest (80.7% economic interest) in the Cerro Corona Project in
January 2006. |
Key Features
|
Independent Audit |
|
Figures reported in this declaration are as reviewed and approved by external consultants as at
30 June 2009 |
|
Prepared by |
|
Gold Fields Limited |
|
Effective date |
|
30 June 2009 |
|
Source of Information |
|
This Technical Statement is a summary of the detailed internally sourced document entitled F2010 Cerro Corona
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 Cerro Corona deposit, centred 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, a
city of more than 100,000 people and approximately 600 km north-northwest of Lima the capital of Peru |
|
Licence Status and Holdings |
|
The mining rights owned by Cerro Corona cover an area of 2,940 ha. The surface rights related to the Cerro Corona
Project is 945 ha. Cerro Corona is owned by Gold Fields La Cima S.A. (GFLC) |
|
Operational Infrastructure |
|
Cerro Corona Mine operates one open pit operation and one copper gold flotation plant at elevations ranging from
approximately 3,600 to 4,000 m above mean sea level |
|
Climate |
|
No extreme climatic conditions are experienced that may affect mining operations |
|
Deposit Type |
|
The Cerro Corona copper-gold deposit is typical of porphyry style mineralization comprising stockwork quartzpyrite-
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 2024 |
|
Environmental |
|
Cerro Corona’s environmental objective is to achieve the ISO 14001 certification during this calendar year. The final
certification audit is planned for October 2009 |
|
Regulatory Codes |
|
Gold Fields Limited 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). The
Mineral Resources and Mineral Reserves are underpinned by sufficient Mineral Resource Management process
and protocol to ensure adequate corporate governance in respect of the intent of the Sarbanes-Oxley Act.
In June 2009 the Lima Stock Exchange (www.bvl.com.pe) registered Gold Fields La Cima S.A. in the Good
Corporate Governance Index (IBGC). This index, which is adjudicated on a yearly basis, includes the top nine listed
companies in Peru, that exhibit the best practices in transparency, social responsibility, equity, trust and information
integrity for their shareholders and stakeholders |
Gold Fields has
stated that: “If we cannot mine
safely, we will not
mine”. This principle
is embedded at
Cerro Corona. |
Operating Statistics
F2009 |
|
|
Waste Mined |
‘000 tons |
|
4,894 |
|
5,762 |
|
|
Sulphide Tons mined |
‘000 tons |
|
5,044 |
|
939 |
|
|
Strip Ratio |
w:o |
|
1.0 |
|
6.1 |
|
|
Au Head Grade |
g/t |
|
1.2 |
|
1.2 |
|
|
Cu Head Grade |
% |
|
0.8 |
|
0.4 |
|
|
Tons Milled |
‘000 tons |
|
4,547 |
|
– |
|
|
Au Head Grade |
g/t |
|
1.24 |
|
- |
|
|
Cu Head Grade |
% |
|
0.80 |
|
- |
|
|
Concentrate Produced |
tons |
|
118,848 |
|
- |
|
|
Gold Produced |
koz |
|
105 |
|
- |
|
|
Copper Produced |
tons |
|
23,947 |
|
- |
|
|
Total Gold Equivalent Produced |
eq koz |
|
219 |
|
- |
|
|
Total Gold Equivalent Sold |
eq koz |
|
218 |
|
- |
|
|
Operating Cost |
US$/oz |
|
394 |
|
- |
|
|
Capital Expenditure |
US$/oz |
|
532 |
|
|
|
|
NCE |
US$/oz |
|
926 |
|
- |
|
|
Total Cash Cost |
million US$ |
|
80.3 |
|
- |
|
|
Total Cash Cost |
US$/oz |
|
369 |
|
- |
|
|
Number of Employees |
personnel |
|
310 |
|
277 |
|
|
Expected LoM |
years |
|
15 |
|
16 |
|
|
Reserves |
million tons |
|
89.3 |
|
94.1 |
|
|
Au Head Grade of Mineral Reserves |
g/t |
|
1,0 |
|
1.0 |
|
|
Cu Head Grade of Mineral Reserves |
% |
|
0.50 |
|
0.51 |
|
Rounding off of figures presented in this report may result in minor computational discrepancies, where this occurs it
is not deemed significant.
Geological Setting and Mineralisation
The Cerro Corona Project is located in
northern Peru on the eastern slope of the
western mountain range of the Andes. The
copper-gold deposit is a typical porphyrystyle
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 m above mean sea level.
The Cerro Corona copper-gold porphyry is one
of fourteen known Tertiary-aged porphyry Cu-
Au-Mo deposits and nineteen epithermal Au-Ag
deposits located in the Cajamarca Metallogenic
Province (CMP) of northern Peru. There are two
well mineralised districts within the CMP. These
are the Yanacocha district in the south of the
province, which is host to the largest producing
gold mine in South America, and the Hualgayoc
Mining District in the north which is one of the
oldest mining districts in Peru, 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 million ounces 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 315° and steep
southwest dips. Faulting is generally restricted
to normal and oblique slip faults with offsets of a
few metres to a few tens of metres.
Local geology
The Cerro Corona copper-gold deposit is
hosted by a 600 to 700 m diameter subvertical
cylindrical-shaped diorite porphyry
emplaced in mid-Cretaceous limestone, marls
and siliclastic 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 in comparison 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 is probably comprised of four
or five satellite stocks with the last two being
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).
|
Regional Geology of the Cerro Corona area |
The intrusive has been emplaced at the
intersection of Andean-parallel and Andeannormal
(transandean) structures, which is a
typical feature of the Cajamarca Metallogenic
Province. A dominant northeast-southwest
trending fault system running through the
intrusive is referred to as the Mariela Fault
trend and has an important relationship with
the distribution of 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, allowing 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.
|
|
|
Sheeted and stockwork quartz-pyrite-marcasite-chalcopyrite ± bornite ± hematite ± magnetite veining |
|
Blasthole drilling |
|
|
|
|
|
|
3D structural model of principal faults in the Cerro Corona deposit |
|
|
Geological domains
Oxidation,weathering,leaching and subsequent
secondary enrichment has led to the formation
of four mineral domains with distinctly different
metallurgical behaviour. The top-most domain,
the Oxide Domain, is characterised by the
complete removal of copper mineralisation
through the action of 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 comprises
parts of the sulphide zone, which is separated
into three domains on the basis of degree of
oxidation and consequent change in sulphide
mineralogical composition. The sulphide zone
has three main domains, which from top to
bottom are the Mixed Domain, the Supergene
Domain and the Hypogene Domain.
The Hypogene Domain is the primary sulphide
zone. The Supergene Domain is an enriched
copper blanket comprising chalcocitecovellite-
chalcopyrite with grades in the range
of 1% Cu.
Exploration and drilling
Exploration in the district continues on the
50:50 joint venture project with Compania
de Minas Buenaventura S.A.A.
|
Location of mineral zones within 2009 design pit |
|
North south section through the Cerro Corona intrusion, showing interpreted geological and resource domains |
Mining
The Cerro Corona deposit is mined by
conventional surface mining methods.
The final surface mine area is expected to cover
some 900 x 500 m. The mining operation is
extending from the crest of the original Cerro
Corona hill, which peaked at 3,964 mRL, to a
final depth at around 3,660 mRL.
Bulk mining will utilise 10 m benches with
loading planned by a combination of a diesel
hydraulic face shovel (230 t) and a rubber tired
front end loader (190 t) loading and six (150 t)
dump trucks. At this stage it is assumed that
all of the material requires drilling and blasting
(with varying powder factors) utilising 200 mm
holes for 10 m benches.
Mine planning and scheduling
Cerro Corona’s LoM plan is based on detailed
Geological and Mineral 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
Bivariate Local Uniform Conditioning model
(BLUC) that has been developed by internal
Gold Fields Limited geostatistical consultants.
Geotechnical and geochemical models for
waste materials have also been developed
and are used in the LoM as an effective Acid
Rock Drainage (ARD) management strategy.
The planning cycle commences with the
ratification of key input parameters prior to
producing a compliant Mineral Resource
statement. The planning process starts after
the construction of the resource model and
incorporates the following considerations:
- Corporate decision 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.
Subsequently, development of a broad
economic sequence and an optimum ultimate economic pit shell;
- Development of a pit design and push backs
applying mine design parameters; and
- The resource model contained within the pit
design is scheduled with consideration of
impacting factors such as the following:
– Economic evaluation of 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; and
– Constraints related to the deposition of
tailings and overburden material.
Open pit optimisations are built using Whittle
4X© – (Multi-element standard mine design
software) on the BLUC 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. The work undertaken includes:
- Geotechnical review and pit wall angle
recommendation;
- Cost review;
- Pit optimisation; and
- Sensitivity analysis
|
|
|
View of the Cerro Corona pit from Cerro Candela |
|
View of the rhyolite quarry for TSF construction material |
Projects
The Cerro Corona Pit is considered to be the
LoM project. The upside potential is controlled
by the availability to place and store tailings.
Efforts to find additional storage capacity are
ongoing.
Mineral Processing
Commissioning and ramp-up of the processing
plant was performed in parallel, to optimise the
operational timing between these two activities.
The ramp-up to full monthly production levels
was achieved by December 2008.
From January 2009, the plant has been
operating at near stable conditions with the
only influence on the optimal performance
resulting from the high variability of the ore feed.
This variability is attributed to the complexities
arising from the varying degree of sulphide
oxidation in the different mineral domains such
as the Mixed Ore and the Supergene Ore.
The various ore types from the mine are
stockpiled on the Run of Mine pad. They are
fed in appropriate blends by front end loader to
the crushing plant. This comprises two mineral
sizers in parallel, one of which is a standby unit.
Mineral sizers 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 SAG mill and
a ball mill in closed circuit with cyclones for
classification. Cyclone overflow represents
the final milled product which feeds the
flotation plant consisting of two sections.
The rougher-scavenger flotation produces a
bulk concentrate, which is then reground and
upgraded to smelter copper grade in the four-stage
cleaner flotation section.
The final concentrate is thickened and filtered
before being stockpiled for final shipment
to the smelters. The thickened rougher-scavenger
flotation tails and the tails from the
cleaner flotation are pumped to the tailings
storage facility.
Training of qualified plant operators has been
successfully achieved at Cerro Corona. Sixty
people from the DIA (Direct Influence Area)
were selected for a comprehensive seven-month
training program comprising theory/
practical training, and exposure to existing
Peruvian copper operations.
Sustainable Development
Cerro Corona commenced implementing it’s
Health and Safety Management System in
July 2008 in accordance with OHSAS 18001
and Corporate requirements. The objective of
the Health and Safety Management System is
to prevent injuries, occupational illness, and
property damage and process loss.
|
|
|
View of the Cerro Corona process plant |
|
View of the SAG and Ball Mills in the process plant |
|
|
|
View of the Aguilas TSF construction site |
|
|
No fatalities were recorded in F2009.
Only two Lost Time Injuries (LTI) were recorded
during the year and 2.3 million Man Work Hours
without any LTI’s were accumulated. The Lost
Day Injury Frequency Rate (LDIFR) improved
from 0.96 in F2008 to 0.25. Cerro Corona was
awarded the Safety Mining Award (second
place) for Peru, a competition that is organized
by the Safety Mining Institute of Peru.
Cerro Corona’s environmental objective is to
achieve the ISO 14001 certification during this
calendar year. The final certification audit is
planned for October 2009.
Mineral Resources and Mineral Reserves
Mineral Resources are reported as in-situ 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 statements include Measured, Indicated and Inferred Mineral Resources.
The Mineral Resources are reported from the Bivariate Localised Uniform Conditioned model at a Net Smelter Return (NSR) cut-off of US$10.92/t
and constrained within an optimised Whittle Pit Shell, based on the same economic parameters as the NSR calculation. (For comparative purposes,
the NSR cut-off applied to the current Mineral Resources is 30% higher than was declared in the June 2008 CPR at US$8.40/t).
Gold equivalent ounces are defined as a quantity of metal (such as copper) converted to an amount of gold in ounces, based on accepted
gold and other metal prices i.e. The accepted total value of the metal based on its weight and value thereof divided by the accepted value of
one troy ounce of gold.
Mineral Resources
June 2009 |
|
June 2009 |
|
June 2009 |
|
|
Open Pit |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Measured |
27.5 |
|
31.9 |
|
44.6 |
|
1.0 |
|
1.0 |
|
0.9 |
|
894 |
|
1,051 |
|
1,224 |
|
|
Indicated |
116.7 |
|
137.8 |
|
170.2 |
|
0.8 |
|
0.8 |
|
0.7 |
|
2,940 |
|
3,336 |
|
3,632 |
|
|
Inferred |
4.9 |
|
10.5 |
|
15.8 |
|
0.5 |
|
0.5 |
|
0.4 |
|
81 |
|
155 |
|
182 |
|
|
Total Open Pit |
149.1 |
|
180.2 |
|
230.7 |
|
0.8 |
|
0.8 |
|
0.7 |
|
3,915 |
|
4,542 |
|
5,038 |
|
|
Surface stockpiles |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Measured |
6.7 |
|
2.8 |
|
0.0 |
|
1.4 |
|
1.5 |
|
0.0 |
|
295 |
|
135 |
|
0 |
|
|
Total surface |
6.7 |
|
2.8 |
|
0.0 |
|
1.4 |
|
1.5 |
|
0.0 |
|
295 |
|
135 |
|
0 |
|
|
Grand Total |
155.8* |
|
183.0 |
|
230.7 |
|
0.8 |
|
0.8 |
|
0.7 |
|
4,209 |
|
4,677 |
|
5,038 |
|
June 2009 |
|
June 2009 |
|
June 2009 |
|
|
Open Pit |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Measured |
26.7 |
|
29.0 |
|
39.6 |
|
0.5 |
|
0.5 |
|
0.5 |
|
305 |
|
345 |
|
415 |
|
|
Indicated |
115.6 |
|
135.1 |
|
165.7 |
|
0.4 |
|
0.4 |
|
0.4 |
|
1,076 |
|
1,215 |
|
1,370 |
|
|
Inferred |
4.8 |
|
10.4 |
|
15.8 |
|
0.3 |
|
0.3 |
|
0.2 |
|
35 |
|
69 |
|
84 |
|
|
Total Open Pit |
147.0 |
|
174.5 |
|
221.1 |
|
0.4 |
|
0.4 |
|
0.4 |
|
1,416 |
|
1,629 |
|
1,869 |
|
|
Surface stockpiles |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Measured |
1.2 |
|
0.6 |
|
0.0 |
|
0.5 |
|
0.6 |
|
0 |
|
14 |
|
8 |
|
0 |
|
|
Total surface |
1.2 |
|
0.6 |
|
0.0 |
|
0.5 |
|
0.6 |
|
0 |
|
14 |
|
8 |
|
0 |
|
|
Grand Total |
148.2* |
|
175.2 |
|
221.1 |
|
0.4 |
|
0.4 |
|
0.4 |
|
1,429 |
|
1,637 |
|
1,869 |
|
June 2009 |
|
June 2009 |
|
June 2009 |
|
|
Copper as Gold Equivalent
(Cu-Au Eq) |
|
|
|
|
|
|
|
|
|
|
|
|
3, 931 |
|
4,297 |
|
5,030 |
|
|
Grand Total Gold Equivalent (Au+Cu-Au Eq) |
|
|
|
|
|
|
|
|
|
|
|
|
8,140 |
|
8,974 |
|
10,068 |
|
* Oxide Mineral Resource contains gold only resulting in the difference in tonnage
Modifying factors
- Mineral Resources and Mineral Reserves are
quoted at an appropriate in-situ 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 required to be mined
to extract the complete pay portion of the
Resource;
- All Mineral Resources and Mineral Reserves
are quoted as at 30 June 2009;
- 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
Run-of-Mine (ROM) grades and tonnages
as delivered to the metallurgical processing
facilities;
- Mineral Reserve statements include only
Measured and Indicated Mineral Resources,
modified to produce Mineral Reserves and
contained in the LoM plan; and
- 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.
|
Resource Gold Price |
US$/ oz |
1,000 |
|
|
Resource Copper Price* |
US$/lb |
2.20 |
|
|
Reserve Gold Price |
US$/ oz |
800 |
|
|
Reserve Copper Price* |
US$/lb |
1.75 |
|
|
Resource Cut off grade |
NSR (US$) |
10.92 |
|
|
Reserve Cut off grade |
NSR (US$) |
10.92 |
|
|
Stripping ratio |
Waste: ore |
0.81 |
|
|
Dilution |
% |
- |
|
|
Plant Recovery Factor (Au) – Mixed |
% |
55 |
|
|
Plant Recovery Factor (Cu) – Mixed |
% |
58 |
|
|
Plant Recovery Factor (Au) – Supergene |
% |
72 |
|
|
Plant Recovery Factor (Cu) – Supergene |
% |
84 |
|
|
Plant Recovery Factor (Au) – Hypogene |
% |
75 |
|
|
Plant Recovery Factor (Cu) – Hypogene |
% |
89 |
|
* Whittle shells run at US$2.20/lb for Mineral Resources
and US$1.75/lb for Mineral Reserves. However
US$2.75/lb and US$2.2/lb were used to calculate
equivalent gold ounces for Mineral Resources and
Mineral Reserves and to compare cash
flows.
Grade tonnage curves
Sulphide Mineral Resource
Oxide Mineral Resource
Mineral Reserves
June 2009 |
|
June 2009 |
|
June 2009 |
|
|
Open Pit |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Proved |
21.5 |
|
23.6 |
|
27.7 |
|
1.1 |
|
1.1 |
|
1.1 |
|
756 |
|
843 |
|
1,016 |
|
|
Probable |
66.6 |
|
69.9 |
|
70.2 |
|
0.9 |
|
1.0 |
|
1.0 |
|
2,017 |
|
2,145 |
|
2,160 |
|
|
Total Open Pit |
88.1 |
|
93.5 |
|
98.0 |
|
1.0 |
|
1.0 |
|
1.1 |
|
2,773 |
|
2,988 |
|
3,176 |
|
|
Surface stockpiles |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Proved |
1.2 |
|
0.6 |
|
0.0 |
|
1.2 |
|
1.4 |
|
0 |
|
49 |
|
29 |
|
0 |
|
|
Total surface stockpiles |
1.2 |
|
0.6 |
|
0.0 |
|
1.2 |
|
1.4 |
|
0 |
|
49 |
|
29 |
|
0 |
|
|
Grand Total |
89.3 |
|
94.1 |
|
98.0 |
|
1.0 |
|
1.0 |
|
1.0 |
|
2,822 |
|
3,017 |
|
3,176 |
|
June 2009 |
|
June 2009 |
|
June 2009 |
|
|
Open Pit |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Proved |
21.5 |
|
23.6 |
|
25.8 |
|
0.6 |
|
0.6 |
|
0.6 |
|
266 |
|
305 |
|
353 |
|
|
Probable |
66.6 |
|
69.9 |
|
68.2 |
|
0.5 |
|
0.5 |
|
0.5 |
|
708 |
|
748 |
|
736 |
|
|
Total Open Pit |
88.1 |
|
93.5 |
|
94.0 |
|
0.5 |
|
0.5 |
|
0.5 |
|
974 |
|
1,053 |
|
1,089 |
|
|
Surface stockpiles |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Proved |
1.2 |
|
0.6 |
|
0 |
|
0.5 |
|
0.6 |
|
0 |
|
14 |
|
8 |
|
0 |
|
|
Total surface stockpiles |
1.2 |
|
0.6 |
|
0 |
|
0.5 |
|
0.6 |
|
0 |
|
14 |
|
8 |
|
0 |
|
|
Grand Total |
89.3 |
|
94.1 |
|
94.0 |
|
0.5 |
|
0.5 |
|
0.5 |
|
988 |
|
1,061 |
|
1,089 |
|
June 2009 |
|
June 2009 |
|
June 2009 |
|
|
Copper as Gold Equivalent
(Cu-Au Eq) |
|
|
|
|
|
|
|
|
|
|
|
|
2,717 |
|
2,857 |
|
2,720 |
|
|
Grand Total Gold Equivalent (Au+Cu-Au Eq) |
|
|
|
|
|
|
|
|
|
|
|
|
5,539 |
|
5,874 |
|
5,896 |
|
|
View of the Gordas TSF from Cerro Candela |
Mineral Resources and Mineral Reserves Reconciliation year-on-year
Mineral Resource
Factors that affected Mineral Resource reconciliation:
- Decreases resulting from depletion, a rise in the NSR cut-off and
geotechnical factors.
Change in Gold Mineral Resource F2009 to F2010
Change in Copper Mineral Resource F2009 to F2010
Mineral Reserve
Factors that affected Mineral Reserve reconciliation:
- Decrease resulting from depletion.
Change in Gold Mineral Reserve F2009 to F2010
Change in Copper Mineral Reserve F2009 to F2010
Mineral Reserve sensitivity
Improved Mineral Resources and Mineral Reserves potential are
influenced by increased commodity prices, but is limited by the size
of the Tailings Storage Facility (94.1 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
|
Note: Cerro Corona is currently Tonnage constrained due to the current capacity of it`s tailings facility.
Adoption of possible TSF expansion opportunities will provide the mine with future upside potential. |
Regulatory Codes
SAMREC
This 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).
JSE
This Technical Statement has been prepared in
compliance with the listing requirements of the JSE Securities Exchange, South Africa (JSE),
specifically Section 12 – Issue 11.
Sarbanes-Oxley Act
The Mineral Resource and Mineral Reserve is
underpinned by an adequate Mineral Resource
Management process and protocol to ensure
adequate corporate governance in respect of
the intent of the Sarbanes-Oxley Act.
Environmental
Cerro Corona has an environmental
management team who are supported by
specialist assistance from corporate office
in Johannesburg. The systems, procedures,
training etc. are at international best practice
levels. Gold Fields Limited has produced a
Sustainability Report in 2009 and intends
reporting annually in accordance with the
Global Reporting Initiative.
Competent Persons
Julian Misiewicz: Consulting Geologist
BSc (Hons) Geology, MSc Geology. Mr Misiewicz is a Fellow of the Society of Economic Geologists (SEG 541613). He has 31 years experience in the
mineral exploration and mining industry and is responsible for the overall correctness, standard and compliance of this declaration.
Alberto Cardenas: Mining Operations Manager
Civil Engineer (CIP 62693), Pontificia Universidad Católica del Perú. Mr Cardenas has 15 years experience in the mining industry, and has held senior
positions in construction and mining. He is responsible for the management of the Mining and Geology Department and related functions.
Eddie Garcia: Chief Mining Engineer
Mine Engineer (CIP 109603), Pontificia Universidad Católica del Perú. Mr Garcia has 12 years experience in mining engineering and 3 years in
Business Planning at Minera Yanacocha. Mr Garcia is responsible for the Mineral Resource Management at Cerro Corona.
Hugo Solis: Long Term Engineer
Mining Engineer (CIP 77973), Universidad Nacional Mayor de San Marcos. Mr. Solis has 14 years experience in surface and underground mining
operations
Oscar Retto
Resource Manager, Universidad Nacional Mayor de San Marcos, specialized in Geostatistics at the Paris School of Mines. Mr Retto has over 15 years
working in exploration and mining companies as a resource modeller and geostatistician in Canada, Australia and Peru. Currently, is responsible for
the Geology Department at Cerro Corona mine
Key Technical Staff
|
Post |
Incumbent |
Qualifications |
Years |
|
Key Responsibilities |
|
|
Head of Operations |
Manuel Diaz |
Metallurgical Engineer |
25 |
|
Responsible for the overall strategic direction, leadership & management |
|
|
Mining:
Senior Manager: Mine |
Alberto Cardenas |
Civil Engineer, MBA |
15 |
|
Mine Operations, Engineering. Geotechnical and Mine Geology management |
|
|
Mineral Resources:
Manager: chief engineer
And resource management |
Eddie Garcia |
Mining Engineer, MBA |
15 |
|
Mine Planning, Mineral Resources & Mineral Reserves and the compilation of CPR |
|
|
Regional Chief Financial
Officer |
Rodolfo Michels |
BS in Business Administration
Certified Professional Accountant
Reg. Chartered Accountant |
38 |
|
Financial management, reporting and compliance |
|
|
Human Resources:
Senior Manager: Human Resources |
Jaime
Obreros |
Attorney in Law |
29 |
|
Human resources, Training & development |
|
|
Metallurgy:
Senior Manager: Process |
Ruben Zevallos |
Metallurgical Engineer |
26 |
|
Mineral Processing and Metallurgy |
|
|
Engineering: Senior
Manager:Engineering and
Construction |
Carlos Herrera |
Electrical & Mechanical Engineering,
MBA |
29 |
|
Engineering, logistics and infrastructure management |
|
|
Environmental Manager |
Luis Alberto Sanchez |
MSc Environmental Services
Mechanical Engineer |
27 |
|
Environmental management |
|
Cerro Corona History
at a Glance
|