Q4 Production Report

Antofagasta PLC
25 January 2006



The following statement has been released by Antofagasta plc and is distributed
in London by Bankside Consultants Ltd on behalf of the Company. Contact: Keith
Irons, 020 7367 8873.

25 January 2006

Antofagasta plc
Quarterly Production Report - Q4 2005

Highlights

• Group annual production of payable copper for 2005 reached 467,300
  tonnes as forecast.

• Molybdenum production at Los Pelambres increased 10.9% over 2004 to
  8,700 tonnes.

• Group cash costs for 2005 were reduced to an annual record low of 13.9
  c/lb due to improved by-product credits. Cash costs at Los Pelambres were
  negative 17.1 c/lb.

Group Total     
                           Q1      Q2      Q3      Q4     Full Year   Full Year
                          2005    2005    2005    2005        2005        2004

Total production of
payable copper           118.9   108.5   116.0   123.9       467.3       498.4
('000 tonnes)

Total production of
payable moly               2.2     2.5     2.0     2.0         8.7         7.9
('000 tonnes)

Weighted average          (7.9)   (9.6)   31.2    39.1        13.9        24.3
cash costs (cents
per pound)

Los Pelambres

Los Pelambres produced 86,900 tonnes of payable copper in Q4, the highest
quarterly volume of the year. Annual production for 2005 reached 322,800 tonnes,
with shipments of 318,100 tonnes. As expected under the mine plan, production
decreased by 7.9% compared to the previous year. This was mainly due to a lower
ore grade of 0.80% in 2005 compared with 0.88% in 2004, which was partly offset
by a 1.8% increase in throughput which reached an average of 128,100 tonnes per
day (tpd).

Molybdenum production in Q4 was similar to Q3 at 2,000 tonnes. Total production
for 2005 reached 8,700 tonnes, an increase of 10.9% over 2004, with shipments in
the year of 8,500 tonnes. By-product credits (excluding period-end
mark-to-market adjustments) more than doubled in 2005 to 91.8 c/lb due to higher
molybdenum market prices (which in 2005 averaged US$32 per pound (2004 - US$16.2
per pound)) as well as increased production.

Cash costs before by-product credits were 74.7 c/lb in 2005. The increase of 21
c/lb over 2004 was mainly due to industry cost pressures, principally higher TC/
RCs for copper concentrate and higher roasting charges for molybdenum
concentrate which together increased by 11.1 c/lb to 27.6 c/lb in 2005. Other
cost pressures included fuel, energy and steel prices as well as the
strengthening of the Chilean peso against the US dollar. Operational factors
included the impact of longer haulage distances within the mine and higher fleet
maintenance costs. Nevertheless, net cash costs fell from 7.9 cents per pound in
2004 to a record negative 17.1 cents per pound this year due to very strong
by-product credits.

El Tesoro

Copper production in Q4 was 24,300 tonnes. Annual production for 2005 reached
98,100 tonnes, which compared favourably with 97,800 tonnes produced in 2004, as
the higher ore throughput level compensated for the expected lower ore grade.

Cash costs for 2005 were 66.1 c/lb, an increase of 13.7 c/lb compared with 2004.
This increase was due to a higher waste-to-ore ratio, lower ore grades and cost
pressures including higher water costs indexed to the copper price, the stronger
Chilean peso and higher fuel, energy, and sulphuric acid prices.

Michilla

Copper production during Q4 was 12,700 tonnes, the highest quarterly figure in
2005. Total production for the year reached 46,400 tonnes, a decrease of 7.2%
compared to the previous year due to lower throughput and slightly lower ore
grades. The lower throughput was due to previously reported operational issues
at the underground mine (since resolved) which necessitated changes in the mine
working sequence and modifications required to the secondary crushing line.

Cash costs reached 118.8 c/lb in 2005, 33.2 c/lb over the previous year, due
both to operational factors and industry cost pressures. Operational factors
included the lower ore grade in the open pit due to old mine workings, a higher
waste-to-ore ratio and the above-mentioned operational issues. Cost pressures
included the strengthening of the Chilean peso, higher acid prices and to a
lesser extent higher fuel costs.

Transport

Rail and road transport volumes in 2005 were 4.3 million tons and 1.5 million
tons respectively. The combined volumes were very marginally below 2004 due to
minor temporary differences in volumes moved by some customers.

Water

The water business continued to perform well in 2005, with sales volumes
reaching 33.1 million cubic metres, an increase of 1.5% compared to last year.

Los Pelambres
                           Q1       Q2      Q3      Q4     Full Year   Full Year
                         2005     2005    2005    2005        2005        2004

Daily average ore
treated ('000 tonnes)   129.0    124.0   131.9   127.6       128.1       125.9

Average copper ore
grade (%)                0.79     0.77    0.80    0.83        0.80        0.88

Average copper
recovery (%)             91.0     90.2    88.4    87.6        89.2        89.1

Copper concentrate
produced ('000 tonnes)  222.0    202.6   220.9   219.6       865.1       948.8

Average copper
concentrate grade (%)    37.5     38.6    39.0    38.8        38.5        38.2

Fine copper in
concentrate              83.3     76.9    83.7    89.9       333.8       362.6
('000 tonnes)

Payable copper in
concentrate ('000
tonnes)                  80.6     74.4    81.0    86.9       322.8       350.6

Average moly ore 
grade (%)               0.024    0.025   0.021   0.019       0.022       0.022

Average moly    
recovery (%)             78.1     81.9    79.9    79.4        79.9        79.6

Payable moly in
concentrate ('000
tonnes)                   2.2      2.5     2.0     2.0         8.7         7.9

Cash costs (before
by-product) (cents per
pound)                   64.0     76.2    75.6    82.5        74.7        53.7

By-product credits     (109.9)  (126.8)  (70.0)  (65.5)      (91.8)      (45.8)
(cents per pound)

Cash costs              (45.9)   (50.6)    5.6    17.0       (17.1)        7.9
(cents per pound)


El Tesoro   
                             Q1     Q2     Q3     Q4    Full Year    Full Year
                           2005   2005   2005   2005         2005         2004

Daily average ore treated  26.3   22.9   29.0   30.4         27.2         25.4
('000 tonnes)

Average ore grade          1.34   1.41   1.14   1.08         1.23         1.35
(%)

Average recovery           82.4   81.8   75.0   81.6         80.2         78.1
(%)

Copper cathodes            26.3   23.6   24.0   24.3         98.1         97.8
('000 tonnes)

Cash costs                 57.8   60.1   73.1   74.1         66.1         52.4
(cents per pound)


Michilla   
                           Q1      Q2      Q3      Q4     Full Year   Full Year
                          2005    2005    2005    2005        2005        2004

Daily average ore         15.3    14.5    14.9    15.0        14.9        16.1
treated ('000 tonnes)

Average ore grade         1.09    0.99    1.11    1.20        1.10        1.11
(%)

Average recovery          76.1    75.7    74.8    75.2        75.4        75.4
(%)

Copper cathodes           12.0    10.6    11.1    12.7        46.4        50.0
('000 tonnes)

Cash costs               102.4   123.2   127.6   123.0       118.8        85.6
(cents per pound)


Transport
                            Q1      Q2      Q3      Q4     Full Year   Full Year
                          2005    2005    2005    2005        2005        2004

Rail tonnage transported 1,126   1,090   1,085   1,035       4,336       4,479
('000 tons)

Road tonnage transported   348     379     395     400       1,522       1,414
('000 tons)


Water  
                           Q1      Q2      Q3      Q4     Full Year   Full Year
                          2005    2005    2005    2005        2005        2004

Water volume sold -
potable and untreated     8,315   8,242   7,969   8,548      33,074      32,575
('000 m3)*


(*) Note: Water volumes include water transportation of 336 thousand m3 in Q1,
    234 thousand m3 in Q2, 236 thousand m3 in Q3 and 241 thousand m3 in Q4.


For further enquiries:

Desmond O'Conor, Antofagasta plc
[e-mail]                             (44) 20 7808 0988

Hussein Barma, Antofagasta plc                        (44) 20 7808 0988
[e-mail]

Alejandro Rivera, Antofagasta Minerals                (56-2) 377 5145
[e-mail]

Issued by:

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

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


                      This information is provided by RNS
            The company news service from the London Stock Exchange