Q4 Production Report

Antofagasta PLC
31 January 2007

31 January 2007

Antofagasta plc

Quarterly Production Report - Q4 2006

Highlights

•   Group annual copper production for 2006 reached 465,500 tonnes (2005 - 
    467,300 tonnes), above the original forecast for the year of 441,500 tonnes.

•   Molybdenum production at Los Pelambres increased by 13% to 9,800 tonnes 
    (2005 - 8,700 tonnes).

•   Group cash costs for 2006 increased by 26.3 cents per pound to 40.2 cents per
    pound. This was due to a combination of higher on-site costs as expected,
    increased tolling charges due to price participation, and reduced by-product
    credits from lower molybdenum prices.

Group Total                        Q1     Q2     Q3    Q4  Full Year  Full Year
                                 2006   2006   2006  2006       2006       2005

Total production of payable     107.0  100.9  126.4 131.2      465.5      467.3
copper ('000 tonnes)
Total production of payable       2.0    2.1    2.9   2.8        9.8        8.7
moly ('000 tonnes)
Weighted average cash costs      49.7   43.9   31.4  38.0       40.2       13.9
(cents per pound)

Los Pelambres

Production of payable copper at Los Pelambres was 93,800 tonnes in Q4, an
increase of 5.6% over the previous quarter. This was due to higher plant
throughput as the 140,000 tonnes per day expansion project continued to impact
processing levels ahead of schedule, together with improved ore grades. Annual
copper production for 2006 was 324,200 tonnes, marginally ahead of 2005. This
was also above the original forecast for 2006 of 308,000 tonnes due to the
better than expected grades and the early implementation of the plant expansion.
Shipments in the year amounted to 324,800 tonnes. For 2007, production is
expected to be approximately 321,000 tonnes.

Molybdenum production in Q4 was 2,800 tonnes, slightly below the previous
quarter, but total production for 2006 reached 9,800 tonnes, an increase of 13%
over the previous year, mainly due to higher molybdenum grades. Shipments in the
year were 9,900 tonnes. Molybdenum production is expected to be approximately
11,000 tonnes in 2007.

Cash costs in Q4 were 14.6 cents per pound compared with 5.7 cents per pound in
Q3, mainly due to lower by-product credits. Cash costs for the 2006 full year
were 16.4 cents per pound, compared with negative 17.1 cents per pound in 2005.
The annual increase was due to a combination of lower by-product credits, higher
tolling charges and increased on-site and shipping costs. By-product credits
decreased by 12.1 cents mainly due to lower molybdenum market prices, which
averaged US$24.8 per pound in 2006 compared with US$32.0 per pound in 2005.
Tolling charges were 12.1 cents higher mainly through price participation with
smelters as the LME copper price averaged 305.3 cents per pound in 2006 compared
with 167.1 cents the previous year. On-site and shipping costs averaged 56.4
cents per pound in 2006, in line with expectations but 9.3 cents per pound above
2005 mainly as a result of cost pressures including oil, plant and machinery
hire and freight.


El Tesoro

Cathode production at El Tesoro in Q4 was 25,600 tonnes, marginally below the
previous quarter. Production for the full year was 94,000 tonnes which
represented a 4.2% decrease from the previous year, as lower expected ore grades
and recoveries offset the increase in ore throughput following the plant
expansion carried out during 2005. Production was nevertheless ahead of the
original forecast for 2006 of 91,600 tonnes. For 2007, production is expected to
be approximately 89,000 tonnes.

Cash costs were 79.1 cents per pound in Q4 and averaged 78.6 cents per pound in
the 2006 full year. Full year costs remained in line with forecast, but
increased compared with 66.1 cents in 2005. The expected increase resulted from
a combination of input cost pressures (including exchange rates and inflation)
and operational factors (including a higher waste-to-ore ratio, higher acid
consumption due to an increased level of carbonates and the effect of the lower
ore grade on production).

Michilla

Michilla produced 11,900 tonnes of copper cathodes in Q4, marginally above the
Q3 production level. Total production in 2006 was 47,300 tonnes. This
represented an increase of 1.9% over the previous year, as a result of increased
throughput and higher recoveries, partly offset by the lower ore grade.
Production was also ahead of the original forecast for 2006 of 41,900 tonnes.
Production is expected to be approximately 43,000 tonnes in 2007.

Cash costs in Q4 were 133.9 cents per pound, an increase of 4.8% over the
previous quarter due to the higher volume of ore treated to compensate for lower
grades and recoveries. Cash costs for the full year were 126.4 cent per pound,
marginally lower than forecast but 7.6 cents per pound higher than 2005. The
increase was mainly due to the higher cost of processing third party materials
and, to a lesser extent, higher input costs.

Transport

The transport division had a successful year, with combined rail and road
tonnages reaching 1.6 million tons in Q4. Full year rail tonnages in 2006
increased by 3.5% compared with the previous year due to increases in the second
half from various mines including the start-up of the Spence copper project.

Water

The water division continued to perform strongly, with Q4 water volumes
increasing to 9.9 million cubic metres, the highest of the year. The volume of
water sold in 2006 increased by 14.3% over the previous year to 37.8 million
cubic metres, as a result both of higher domestic consumption and higher sales
to industrial customers including Spence which started its operations during the
second half of this year.



Los Pelambres                    Q1     Q2     Q3     Q4  Full Year  Full Year
                               2006   2006   2006   2006       2006       2005
Production statistics

Daily average ore treated     120.9  119.5  130.0  139.1      127.4      128.1
('000 tonnes)
Average ore grade              0.81   0.84   0.78   0.83       0.81       0.80
(%)
Average recovery               88.1   88.2   89.3   89.2       88.7       89.2
(%)
Concentrate produced          194.8  200.2  207.4  240.3      842.6      865.1
('000 tonnes)
Average concentrate grade      39.6   40.0   40.2   39.6       39.9       38.5
(%)
Fine copper in concentrate     76.6   69.8   91.8   97.0      335.2      333.8
('000 tonnes)
Payable copper in concentrate  74.1   67.5   88.8   93.8      324.2      322.8
('000 tonnes)

Average moly ore grade        0.026  0.027  0.028  0.029      0.028      0.022
(%)
Average moly recovery          74.4   76.0   77.8   75.8       76.1       79.9
(%)
Payable moly                    2.0    2.1    2.9    2.8        9.8        8.7
('000 tonnes)

Cash costs statistics

On-site and shipping costs     54.5   56.8   56.5   57.7       56.4       47.1
(cents per pound)
Tolling charges for            34.8   45.4   41.9   37.3       39.7       27.6
concentrates (cents per pound) 
By - product credits          (59.5) (83.7) (92.7) (80.4)     (79.7)     (91.8)
(cents per pound) *
Cash costs                     29.8   18.5    5.7   14.6       16.4      (17.1)
(cents per pound)

(*) Note: By-products credits do not include any costs attributable to the
production of molybdenum concentrate. By-product calculations also do not take
into account unrealised mark-to-market gains at the beginning or end of each
period.


El Tesoro                     Q1     Q2     Q3     Q4  Full Year  Full Year
                            2006   2006   2006   2006       2006       2005

Daily average ore treated   29.7   28.6   27.9   28.7       28.7       27.2
('000 tonnes)
Average ore grade           0.99   1.18   1.25   1.21       1.16       1.23
(%)
Average recovery            77.9   73.9   80.4   80.0       78.1       80.2
(%)
Copper cathodes             20.8   21.8   25.9   25.6       94.0       98.1
('000 tonnes)
Cash costs                  79.6   79.8   76.1   79.1       78.6       66.1
(cents per pound)



Michilla                      Q1     Q2     Q3     Q4  Full Year  Full Year
                            2006   2006   2006   2006       2006       2005

Daily average ore treated   14.6   15.4   15.0   15.8       15.2       14.9
('000 tonnes)
Average ore grade           1.13   1.07   1.03   0.99       1.05       1.10
(%)
Average recovery            76.2   76.4   80.9   79.4       78.2       75.4
(%)
Copper cathodes             12.1   11.6   11.7   11.9       47.3       46.4
('000 tonnes)
Cash costs                 120.2  123.9  127.8  133.9      126.4      118.8
(cents per pound)


Transport                        Q1     Q2     Q3     Q4  Full Year  Full Year
                               2006   2006   2006   2006       2006       2005

Rail tonnage transported      1,122  1,011  1,104  1,249      4,486      4,336
('000 tons)
Road tonnage transported        383    367    361    345      1,456      1,522
('000 tons)


Water                            Q1     Q2     Q3     Q4  Full Year  Full Year
                               2006   2006   2006   2006       2006       2005

Water volume sold - potable   9,304  9,231  9,328  9,935     37,798     33,074
and untreated ('000 m3)**

(**) Note: Water volumes include water transportation of 270,000 m3 in Q1,
740,000 m3 in Q2, 254,000 m3 in Q3, 340,000 m3 in Q4 and total for 2006 of
1,604,000 m3 (compared to 1,047,000 m3 in 2005).


For further enquiries:

Alejandro Rivera
[e-mail]                   Santiago: (56-2) 377 5145

Desmond O'Conor
[e-mail]                London: (44) 20 7808 0988

Hussein Barma                            London: (44) 20 7808 0988
[e-mail]

Issued by:

Keith Irons, Bankside Consultants        London: (44) 20 7367 8873
[e-mail]

Oliver Winters, Bankside Consultants     London: (44) 20 7367 8874
[e-mail]





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