Visit to chilean operations – El Tesoro - Antofagasta plc

Minera El Tesoro
Overview
November , 2004

Location & Ownership
Geology,Mine & Plant
Operational & Financial Achievements

Location & Ownership
Geology,Mine & Plant
Operational & Financial Achievements

Location
The mine is located in the
Atacama Region, 190 km.
Northeast of Antofagasta
in Chile’s Second Region
and 21 km. from the
nearest town, Sierra
Gorda.
It lies at an altitude of
2,300 metres above sea
level.

Ownership
Antofagasta plc
(United Kingdom)
Equatorial Mining Ltd.
(Australia)
100% 100%
Antofagasta Minerals
(Chile)
CCM Leonor
(Chile)
61% 39%
Minera El Tesoro
(Chile)

Location, History & Ownership
Geology,Mine & Plant
Operational & Financial Achievements

Geology
• The drilling campaigns were focused in the
identification and evaluation of the oxides ore
bodies embedded in gravel.
• 368 vertical air reverse drillings were made,
totalizing 71400m.
• The drillholes were distributed in a 70 x 70 m
mesh.

Geology
• El Tesoro type of mineralization

Geology
• El Tesoro an Exotic Deposit

Geology
• The ore body has a lenticular shape with a
smooth inclination of 15°.
• Its maximun extension is 1,5 Km and thickness
is 150 m.
• In the ore body, two separate bodies are
recognized, separated by a level of waste and
low grades.

• Ore Body
Geology

Operating Life:
Reserves:
The Mine
21 years
Average Cu Grade: 0.81%
Proven Reserves: 95%
Ore Body:
178 million tonnes
Exotic origin. Mineralisation of chrysocollas
and atacamite hosted mainly in gravels
Mine: Open pit (1,5km x 1,5km x 240m)
Production Rate:
9,7 million tonnes of ore per year

The Mine
El Tesoro Mine has increased its extraction rate (tpd)
2004: 115 ktpd
2006-2008: 190 ktpd
250 ktpd
25 Mton
42 Mton 60 Mton 70 Mton 70 Mton
70 Mton
200 ktpd
150 ktpd
100 ktpd
50 ktpd
2003
2004 2005 2006 2007 2008

The Plant
Primary
Crushing
Secondary & Tertiary
Crushing
Agglomeration
95%@12.7mm
SERVICES
Leaching
Final Product
Electrowinning
Solvent Extraction

The Plant
9.700.00
95.000 Ton/Año
99.99% Cu

Location, History & Ownership
Geology,Mine & Plant
Operational & Financial Achievements

Labor Relations
Almost 1200 people work at Minera El Tesoro, 400 own staff and
800 contractors.
The work force is mostly young people that has been trained by
the company.
One of the fortress of Minera El Tesoro is the good working
environment, and as a consequence of that the company
obtained the “Great Place to Work” prize, awarded as one of the
10 best evaluated companies to work in.
There is one union syndicate, whose relationships with the
administration of the company are very good.

No of Accidents - FR
20
15
10
5
0
Health & Safety
Corporate Frequency Rate - 2003 - 2004
(Rate: 12 month variable average)
35,1
6,4
Jan FebrMar Apr May Jun Jul Aug Sep Oct Nov DecJan Feb Mar Apr MayJun Jul AugSep Oct Nov Dec
18,5
4,3
25,6
5,5
50
45
40
35
30
25
20
15
10
5
0
TFR
LWD Accidents NLWD Accidents Total Frequency Rate Frequency R.
The reduction goal for the rate of accidents for 2004 is
almost 30%, wich is above any industry standard.

Community & Environment
The company obtained “Orden al Mérito al Buen Vecino” awarded
by Sierra Gorda Community for the US$ 100,000 donation to
provide electric power to the town.
Minera El Tesoro has a program to support the Sierra Gorda
Elementary School, specially in topics related to the environment.
The relations with the community are good, nevertheless the
company thinks that there is big room to growth on this matter.
Action plans to improve are being accounted for the next years.

ROCE 41,5 %.
2004 Challenges
100% Subordinated Debt Repayment (3 1/2 years payback).
27% reduction on accidents rate.
Production record of 96,5 Kton of cathodes (on-grade quality 93%).
Total material moved at the mine increased from 25MT to 42MT.
Improved operational reliability vs 2003.
• new solution of water plant.
• spent ore stacker.
• high carbonate grade at the mineral.
Metallurgical Test
Successfull solving stockpiling Dome incident.
Optimization Project from 9,7 to 10,5 Mton per year.
Implementing business model (EVA and ROCE goals).
Improved work environment v/s 2003.
Reducing impacts on labor due to new projects in the Region.

Financial & Operational Data

MUS$
50
40
30
20
10
0
MUS$
200
150
63
3,0
72
12,5
Financial Data
82
17,6
2001 2002 2003
@ Real Copper Price (MUS$)
ROCE
Senior Debt Balance
Copper Price (c/lb)
c/lb
150
120
90
60
30
0
140
120
100
80
60
40
20
0
(MUS$)
200
150
63
After Tax Profits
41,5
42
3 16
72
83
38
82
2001 2002 2003
Total Sales (ton CuF)
After Tax Profits (MUS$)
Copper Price (c/lb)
Ebitda
92
100
197
185
157
100
63
72
82
50
0
12
40
12
28
2001 2002 2003
50
0
78
25
55
2001 2002 2003
EBITDA (MUS$) Copper Price (c/lb)

Material Mined and Waste Ore Ratio
45.000
40.000
3,18
4,00
3,50
35.000
30.000
25.000
20.000
15.000
10.000
5.000
1,77
12.286
1,98
22.037
2,11
24.571
41.651
3,00
2,50
2,00
1,50
1,00
0,50
2001 2002 2003 2004 (e)
Ktons Mined
Waste Ore Ratio

Ore to Plant and Cu Average Grade
10.000
9.000
8.000
7.000
6.000
5.000
4.000
3.000
2.000
1.000
1,50
1,45
1,40
8.112
1,33
7.466
9.239
4.162
2001 2002 2003 2004 (e)
Kton Ore to Plant Cu Average Grade
1,60
1,50
1,40
1,30
1,20
1,10
1,00

Cathodes Production and Cu Recovery
120.000
100.000
80.000
60.000
40.000
20.000
Project Design Cathode Production
75%
74%
42.971
84.320
78%
92.371
78,4%
96.507
79%
78%
77%
76%
75%
74%
73%
72%
2001 2002 2003 2004 (e)
Tons Cathodes
% Cu Recovery

Cathodes On Grade Quality
100%
95%
90%
97%
Project Design Cathode On Grade Quality
85%
80%
75%
81%
87% 93%
70%
2001 2002 2003 2004
Cathodes Quality

End of Presentation