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Cuiabá Gold Mine – Exploration Success in a Mature
Greenstone Belt – Iron Quadrangle – MG – Brazil
PDAC 2017 – BRAZILIAN MINING DAY Rodrigo Martins
AGENDA AGENDA
AngloGold Ashanti
AngloGold Ashanti Brazil
Iron Quadrangle – GB Rio das Velhas
Cuiabá Mine
Exploration Works & Results
Final Comments
ANGLOGOLD ASHANTI
Exploration Strategy
• Primary focus on countries with synergies to optimize cost and opportunities, targeting > 6 MOz Discovery with
high margin, low capital potential by 2019
• Greenfields Exploration team delivers ounces consistently at <$25/Oz
• Credited with share in eight discoveries from 2001-2015 hosting 73.3 MOz attributable gold in reserves and
resources
• Most gold discovered by any of the profiled companies, almost twice that of nearest competitor
Business Unities
In operation since 1985
Resources & Reserves
7.2MOz / 1.37MOz
Production
5.54 MOz
Production in 2016:
312 KOz
Employees: 1997
CBLM
In operation since 2002
Resources & Reserves
5.7MOz / 0.50MOz
Production
0.57 MOz + 1.8MOz (SB)
Production in 2016:
108 KOz
Employees: 769
CDS
In operation since 1989
Resources & Reserves
3.6MOz / 0.47MOz
Production
4.05 MOz
Production in 2016:
138 KOz
Employees: 1128
MSG
ANGLOGOLD ASHANTI BRAZIL
0
100.000
200.000
300.000
400.000
500.000
600.000
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
Oz
Nova Lima Mines BU Cuiabá Lamego BU CdS BU Serra Grande
GOLD
PRODUCTION
SINCE 1975 –
10MOz
ANGLOGOLD ASHANTI BRAZIL
Mina Velha
Shutdown
Raposos Mine
Shutdown
São Bento Mine
Acquisition
Serra Grande 50%
Acquisition
ANGLOGOLD ASHANTI – BF EXPLORATION
• Resources Addition – 7.9MOz
• Resources Conversion - 2.2MOz
US
$K
KO
z
0
200
400
600
800
1000
1200
1400
1600
1800
2000
0
5.000
10.000
15.000
20.000
25.000
30.000
35.000
40.000
2011 2012 2013 2014 2015 2016 2017
Exploration (US$ M) Resources Conversion EX2A (KOz) Resources Addition EX2B (KOz)
IRON QUADRANGLE
• First geological records from 1720
• Volcanic vs Sedimentary rocks – 10% x 90%
• Hundreds of gold occurrences
• High structural complexity
• Continuity, controls and mineralization styles?
Banded Iron Formation?
• Outcrops / anomalies vs deposits dimensions –
Blind deposits?
• Bonanzas zones vs pinch and swell
• Depth limits
• Models interpretations vs database
IRON QUADRANGLE
• First geological records from 1720
• Volcanic vs Sedimentary rocks – 10% x 90%
• Hundreds of gold occurrences
• High structural complexity
• Continuity, controls and mineralization styles?
Banded Iron Formation?
• Outcrops / anomalies vs deposits dimensions –
Blind deposits?
• Bonanzas zones vs pinch and swell
• Depth limits
• Models interpretations vs database
100MOz Gold Province
35Moz??
2,400m
• 2,500m depth
• 13MOz (400ton Au) produced
• High Cut off
• Shutdown - 1995
• 3.0MOz remains at depth
• No exploration works along the
history
• Full size potential - > 20MOz??
MINA VELHA 1955
IRON QUADRANGLE
CUIABÁ COMPLEX Operations LAMEGO MINE
6 years in operation
LoM: 2024
Main access: ramp
Employees: 321 employees - Payroll
Historical Production Data
Gold produced: 280 KOz / 48 KOzy
Ore Tonnes Produced: 1.2 Mt / 0,45 Mty
Average feed grade: 4.36 g/t
CUIABÁ MINE
30 years in operation
LoM: 2035
Main access: Shaft / ramp
Employees:1,621 employees - Payroll
Historical Production Data
Gold produced: 5.2 MOz / 265 KOzy
Ore Tonnes Produced: 21 Mt / 1,3 Mty
Average feed grade: 7.81 g/t
0
50
100
150
200
250
300
350
400
450
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
Strategic Option Base Case
3.6 MOz Endowment
+4.6 MOz??
Gold Production (KOz/y) BUP 16
5.4 MOz
• Tubular fold - 115/30º
• Major orebodies hosted on BIF + sulphides (pyrite, pyrrothite
and arsenopyrite)
• Satellites orebodies hosted on hydrothermal zones in
metabasalts and metassediments
• Structural controlled
Level 03
CATEGORY Au MOz
P & P 1.37 31 Dec. 2016
Reserves
CATEGORY Au MOz
Measure 2.39
Indicated 1.99
Inferred 2.84
Total: 7.22
Mineral Resources
CUIABÁ COMPLEX
Level 07
Level 12
Level 18
0 1000
Metandesite
BIF
Legend
Deep Drilling
• Tubular fold
• Geometry changing and increasing at depth
• Down plunge continuity still opened
• High structural complexity
Level 4
Level 12
Level 14
Cuiabá Structure Geometry
CUIABÁ COMPLEX
Level 16
Cuiabá Complex – Strategy in Place and Endowment Definition
EXPLORATION STRATEGY
• Increase geological information at depth
• Increase confidence level at depth
• Increase number of production areas from narrow vein orebodies
• Add production from satellite orebodies
100
50
0 25
Margin (%)
Ore
bo
dy
Cap
abili
ty
(Koz/y
)
FGS
2.5MOz
9.44g/t
SER
0.73Moz
11.32g/t
BAL
1.0MOz
9.14 g/t
GAL
0.73Moz
7.86g/tCAR
0.70Moz
5.90g/t
CG
0.2Moz
9.14g/t
CP
0.33Moz
3.96g/t
AV
0.09Moz
3.88g/t
QM
0.18Moz
4.56g/t
GALFW
0.17Moz
8.66g/t
OTHER
0.31Moz
6.18g/t
Cuiabá Main Orebodies
Cuiabá Satellites
Lamego
VQZ
Cuiabá Secondary
Increase confidence level
in depth
Increase number of
productions areas at
Narrow veins
Add production from
Satellites
Increase geological
information in depth
50
>1Moz
Grade g/t
>500 koz
Grade g/t>250 koz
>100
koz
Ore
body
Siz
e
Mineral Resources & Grade
<100
koz
>2Moz koz
Grade g/t
Mine Entrance
(234m)
Level 11
Level 18
Level 32
Level 25
Current Shaft
System
Level 45
Surface Exploration Campaign (2013/15)
ORD – 4Levels
Current Ramp
Position – L18
BST/Inferred Resources – 8 Levels
Resources & Reserves Rationale
From Production
PRODUCTION
4 Levels
Indicated Resources – 4 Levels
4 Levels
8 Levels
FGS (L24)
BAL (L26)
VQz (L21/24)
SER (L23)
Cuiabá Mine – Reserves Addition and Risk Mitigation at Short Term EXPLORATION STRATEGY
Cuiabá Mine – Potential Definition
EXPLORATION STRATEGY
L21
L11
L32
L45
Down
Plunge
Continuity
BST+BSI
1996
Drilling Campaign
Satellites
Deep Drilling 2013-15
Shaft
Deep Drilling 2016-18
+2.0 MOz*
+1.6 MOz??
L18 (Current Operation)
2013 MR = 4.29 MOz
Endowment = 16 MOz??
2018
2015 MR = 5.67 MOz
MR = 6.27 MOz??
Cuiabá Mine – Exploration Progress
0
20.000
40.000
60.000
80.000
100.000
120.000
2009 2010 2011 2012 2013 2014 2015 2016 2017
Met
ers
Mine Geology (Executed) Mine Geology (Program) UG Exploration (Executed)
Surface Exploration (Executed) UG Exploration (Program)
Resources vs Exploration
EXPLORATION STRATEGY
Drilling Progress CB
KOz
0
2.000
4.000
6.000
8.000
10.000
12.000
14.000
16.000
0
1.000
2.000
3.000
4.000
5.000
6.000
7.000
8.000
2009 2010 2011 2012 2013 2014 2015 2016 2017
Measured Indicated Inferred Exploration US$K
DEEP DRILLING
1048m
-137m
-825m
Level 28
Level 24
Level 17
Level 7
CBA13
Shaft
OP
Level 21
Level 11
2013/15 1996 2017
DEEP DRILLING
FGS
FGS
BAL
BAL
GAL GAL
SER
CGA
FGS
SER
PC40 PC43 PC39 PC46
GALFW
VIA
VQZ
SW NE
N20
N21
N22
N23
A
B
Plunge
• US$13M invested since 2013
• 56 positive intersections higher than cut off and 40% outside FFB
• 13 mother drillholes and 9 controlled derivations
• Deepest DDH in Brazil – 2,396m
Au
< 1 g/t
< 2 g/t
> =10 g/t
< 4 g/t
< 10 g/t
DEEP DRILLING • Measurement of the geological structures from
previous drill holes
• Design the geological model of the main ore bodies –
azimuth and changes (structure opening in depth)
• Control the drill hole deviation to reach the expected
zone
117/20
N19
115/15
N28
113/19
N24
115/16
CBA13 plan
CBA13 plan
Simulation
DEEP DRILLING QAQC at core orientation
(comparison reference line in each run)
Structures collection
(mark, describe, photo and measure) Analysis of structures
(fold classification, plunge determination, orientation of the best section)
Draw the structures in 3D
(Draw planes and lines) Selection of structures to built the fold
(Lines from planes) Fold interpretation
(Section perpendicular to the fold axis) Digitalized fold section
(Section will guide the geological model) Fold in S
S1
S0
L2
Plunge
115/16
Beding fold with S1 axial plan
M fold in
hinge zone
Cuiabá Mine – Serrotinho Orebody
L21
L20
0.80m @ 17.39 g/t
1.0m @ 5.16 g/t
19.97m @ 25.3 g/t
&
1.62m @ 8.99 g/t
5.74m @10.15 g/t
0.80m @ 6.04 g/t
Massive Sulfide
SW NE
FGS
BAL
GAL
SER
FGS
VQZ
CGA
Plunge
Az120
L 3
L 11
L18 L21
L24
NE
SW
DEEP DRILLING
L23
L24
L25
L26
3.36m @ 7.19 g/t [email protected] g/t
2.10m @31.84g/t
6.08m @17.17g/t
[email protected]/t [email protected] g/t
Cuiabá Mine – Fonte Grande Sul Orebody
DEEP DRILLING
Cuiabá Mine – Satellites Orebodies – FGS FW – Quartz Vein
[email protected]/t [email protected]/t
L16
L18
L20
L22
VQZ - L17
VGs
Quartz Vein
SATELLITES OREBODIES
SATELLITES ORE BODIES
1.83m m@ 175.8 g/t
0.86 m@ 8.17 g/t
1.95 m@ 10.80 g/t
15.03 m@ 23.86g/t
Main exploration target
44 KOz @ 6.08 g/t per level
(740 Oz/vm)
[email protected]/t [email protected]/t
Level 17
Cuiabá Mine – Satellites Orebodies – FGS FW – Quartz Vein
REGIONAL WORKS – RV3D
Objective
• To understand Cuiabá & Lamego correlation
• To identify and generate new prospective targets
• Add new resources to AngloGold on short term
• New mine portal
Old Working
MCB
LM
CDS
MV RV3D area
QF Map
LAMEGO CUIABÁ
LAMEGO CUIABÁ
FINAL COMMENTS • CUIABÁ MINE
• Cuiabá Mine is a giant deposit >20MOz
• Depth limit is completely undefined
• Multiple ore types – BIF, Quartz veins, metabasalts, etc
• Exploration is the key investment at Cuiabá Strategy
definition
• IRON QUADRANGLE
• IQ still has high potential at gold deposits
• Plunge and mineralization models
• Paradigms and market conditions locked new
discoveries
• The current potential is limited by urban growth and
environmental issues
• IQ is still few explored compared to other gold provinces
• Mina Grande – Why was it just one??
• Recent results from Cuiabá Mine confirms the potential
• Systematic works and technology applied at Exploration
are the keys points at the success
!