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Base Metals

Anglo Base Metals - Projects

The Ore Reserve and Mineral Resource estimates were compiled in accordance with the Australasian Code for Reporting of Mineral Resources and Ore Reserves (The JORC Code, 2004) as a minimum standard. The Mineral Resources are additional to the Ore Reserves.

The figures reported represent 100% of the Ore Reserves and Mineral Resources, the percentage attributable to Anglo American plc is stated separately. Rounding of figures may cause computational discrepancies.

Ore Reserves
Grade Contained metal thousand tonnes
Attributable % Classification 2008 2007 2008 2007 2008 2007
Quellaveco (OP)(1) 80.0  
Copper   %Cu %Cu  
Sulphide Proved 253.3 250.1 0.76 0.76 1,925 1,901
Flotation Probable 636.8 688.3 0.61 0.59 3,885 4,061
  Total 890.1 938.4 0.65 0.64 5,810 5,962
Gamsberg (OP)(2) 74.0  
Zinc   %Zn %Zn  
  Proved 34.2 34.3 7.55 7.55 2,580 2,585
  Probable 110.3 110.3 5.55 5.55 6,124 6,124
  Total 144.4 144.5 6.03 6.03 8,704 8,709
Mineral Resources
Grade Contained metal thousand tonnes
Attributable % Classification 2008 2007 2008 2007 2008 2007
Quellaveco (OP)(1) 80.0  
Copper   %Cu %Cu  
Sulphide Measured 1.9 1.5 0.39 0.53 8 8
Flotation Indicated 193.9 176.7 0.43 0.46 834 813
  Measured and Indicated 195.9 178.2 0.43 0.46 842 821
  Inferred in Mine Plan 21.8 41.1 0.60 0.54 131 222
Pebble (OP/UG)(3)(7)(8)(9) 50.0  
Copper   %Cu %Cu  
  Measured(4) 500.0 655.0 0.34 0.34 1,700 2,227
  Indicated(5) 4,120.0 1,760.0 0.48 0.30 19,776 5,280
  Measured and Indicated 4,620.0 2,415.0 0.46 0.31 21,476 7,507
  Inferred(6) 2,270.0 3,180.0 0.37 0.60 8,399 19,234
Mining method: OP = Open Pit, UG = Underground.
Quellaveco: Based on a feasibility study completed in 2000. Mineral Resources are quoted using a US$ 1.80/lb resource pit constraint. Inferred Mineral Resources with reasonable prospects of eventual economic extraction not considered in the Mine Plan in 2008 are as follows:- (Tt = Thousand tonnes)
Tonnes Grade (% Cu) Contained metal Economic criteria
392.7Mt 0.48% (Tcu) 1,885Tt Pit Shell @US$1.8/lb
Gamsberg: Based on a feasibility study completed in 2000 and reviewed in 2006 to account for prevailing economic and financial assumptions. Ore Reserves have reduced due to mining of approximately 0.06Mt of material with an average grade of 7.28% Zn via the exploration adit which was processed at the Black Mountain concentrator. An optimised pit shell includes Inferred Resources of 54.2Mt with an average grade of 4.10% Zn. Gamsberg is owned by Black Mountain Mining (Pty) Ltd – 74% owned by Anglo Operations Limited and 26% by Exxaro group of companies.
Pebble: Copper Equivalent (CuEq) calculations use metal prices of US $1.80/lb copper, US $800/oz gold and US $10.00/lb for molybdenum. The CuEq calculation takes into consideration the relative difference in recovery between the copper, gold and molybdenum. The estimates of metallurgical recoveries used in the calculation were 91% for copper, 75% for gold and 90% for molybdenum in the western side of the deposits (formerly Pebble West) and 93% for copper, 80% for gold and 94% for molybdenum in the eastern side of the deposit (formerly Pebble East). The estimates of metallurgical recovery are preliminary results from the ongoing Prefeasibility study. For 2007, the calculation of CuEq did not take the relative difference in recoveries into account. By definition, Mineral Resources do not have demonstrated economic viability and neither should it be assumed that all or part of the Inferred Resources will necessarily convert to Indicated or Measured Resources. A test for “reasonable prospects for eventual economic extraction” has been carried out and the mineral resources fall within a volume defined by metal price estimates of US $2.50/lb for copper, US $900/oz for gold and US $25/lb for molybdenum. The resources are based on drilling to June 2008 and a block model created in July 2008. The resources in the table are based on a cut-off grade of 0.4%CuEq. At a cut-off of 0.6%CuEq the estimates of Measured plus Indicated Resources are 3090 million tonnes at 0.56%Cu, 0.42g/t Au and 0.030%Mo (0.96%CuEq).
Pebble co-product estimated grades 2008 (Measured): Gold 0.36g/t, Molybdenum 0.018%. CuEq average grade 0.63%.
Pebble co-product estimated grades 2008 (Indicated): Gold 0.37g/t, Molybdenum 0.027%. CuEq average grade 0.83%.
Pebble co-product estimated grades 2008 (Inferred): Gold 0.35g/t, Molybdenum 0.026%. CuEq average grade 0.71%.
Pebble: Previously the deposit was divided into Pebble West and Pebble East. In 2007 Measured and Indicated Resources were all reported from Pebble West at a cut-off of 0.4%CuEq while for the Inferred Resources, Pebble West (760Mt at 0.27%Cu containing 2,052kt of copper) were reported at a cut-off of 0.4%CuEq and Pebble East (2,420Mt at 0.71%Cu containing 17,182kt of copper) were reported at a cut-off of 0.8%CuEq.
Pebble: Significant changes between 2007 and 2008 resources, include a major upgrade of Inferred Resources in the former Pebble East to Indicated, the change in the cut-off grade of resources reported from the former Pebble East from 0.8%CuEq to 0.4%CuEq, the application of the test for reasonable prospects for eventual economic extraction and the inclusion of relative recoveries in the calculation of the CuEq. Less significant changes were due to classification methodology.
Pebble: The property comprises a continuous block of 1,335 located Alaska State mineral claims which total 98,000 acres (39,659 hectares) and which are currently valid. The claims must be renewed annually before 1 December through the payment of rental fees (approx. US$200,000) and registration of work conducted or payment of cash in lieu (approx. US$250,000). There are no known factors affecting the claims.
The Mineral Resources of the following projects were reviewed during 2008 by independent consultants: Pebble.

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