SANTIAGO, CHILE - Antofagasta PLC reported that Los Pelambres produced 102,500 tonnes of payable copper in Q2 and 186,100 tonnes in the first half of 2010, 18.2% above the first half of 2009, mainly due to higher plant throughput as a result of the plant expansion.

The commissioning of the plant expansion has now been completed with ore throughput in Q2 averaging 174,300 tonnes per day. Shipments of payable copper in the first half of 2010 were 162,400 tonnes, 23,700 tonnes lower than production due to a delay in programmed shipments at the end of June due to adverse weather conditions. The accumulated inventory of filtered concentrate at the port was shipped in July.

Molybdenum production was 2,700 tonnes in Q2 and 4,400 tonnes in the first half of the year, 18.9% above the first half of 2009. The higher production was mainly due to the higher plant throughput, as well as improved ore grades and metallurgical recoveries in Q2.

Cash costs were 63.3 cents per pound in Q2 compared with 74.1 cents per pound in the previous quarter. The higher costs in Q1 were mainly due to a mill relining and major maintenance work that quarter. Cash costs for the first half of 2010 were 68.1 cents per pound, compared with 84.7 cents per pound in the 2009 H1. The decrease in net costs was mainly due to the increase in by-product credits as a result of higher molybdenum market prices and a decrease in tolling charges, partly offset by an increase in on-site and shipping costs in 2010 H1. The increase in on-site and shipping costs was mainly due to higher energy costs

and a stronger Chilean peso compared to the weaker economic environment in the first half of 2009.

Copper production at El Tesoro was 22,900 tonnes in Q2 and 47,300 during the first half of the year, 18.0% above the first half of 2009. This reflects the impact of production from the fully operational Esperanza Run-of-Mine (ROM) oxide leaching project which contributed 7,100 tonnes of cathode production in H1.

Cash costs for Q2 of 159.8 cents per pound were below budget, although higher compared with 134.3 cents per pound in the previous quarter. This increase was due to the impact of inventory movements on costs, an increase in the costs of inputs and the effect of lower production compared with Q1.

Cash costs in the first half of the year were 146.6 cents per pound, a 23.8 cents per pound increase on the 2009 H1 cash costs. This increase is mainly due to the stronger Chilean peso, higher fuel costs, the impact of inventory movements on costs and inclusion of costs for Tesoro North-East and the Run-of-Mine processes. These factors were partly offset by lower sulphuric acid prices.

Michilla produced 9,700 tonnes of copper in Q2, achieving 19,500 tonnes during the first half of the year, which was ahead of budget, although slightly below the first half of 2009, mainly due to lower throughput and metallurgical recoveries.

Cash costs for Q2 were 188.6 cents per pound compared with 172.3 cents per pound in the previous quarter. This increase was mainly due to the decision to process additional lower-grade ore to utilise spare capacity at the plant, as well as the impact of mining from the higher cost Lince open pit, including the resulting increased earth movement in Q2 compared with Q1.

Cash costs were 180.4 cents per pound in the first half of the year, a 33.9 cents per pound increase on the 2009 H1 cash costs. The increase was due to the reopening of the Lince open pit, a stronger Chilean peso and the higher cost of ore purchased from ENAMI partly offset by the lower sulphuric acid cost.

In addition, the company reported that Esperanza remains on track to commence operations during the fourth quarter of 2010. Overall construction was 85% complete at the end of June and pre-stripping was completed during July. The total development cost (including working capital, financing and exchange impacts) is estimated to be $2.5 billion reflecting exchange effects and monthly cost revisions including the impact of the earthquake earlier in the year on

construction activities.

In May, the Group's mining division, Antofagasta Minerals S.A., approved further expenditure of approximately US$70 million on growth options in the Sierra Gorda district for the period to the end of 2011, covering further exploration, the preparation of a prefeasibility study for the district and for infill drilling, geotechnical and metallurgical studies to support eventual feasibility studies at Caracoles and Telegrafo.

At Reko Diq, work on the feasibility study and the related environmental and social impact assessment study is in its final stages. Discussions for agreements with the relevant authorities are continuing.

The company's address is Av. Apoquindo 4001, 18th Floor, 7550162, Las Condes, Santiago, Chile, 56-2-798-7000.