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Mineral Resource and Ore Reserve

– a summary

CREATING VALUE
BY GROWING THE MAJOR ASSET

AngloGold Ashanti‘s Mineral Resource and Ore Reserve are reported in accordance with the minimum standards described by the Australasian Code for Reporting of Exploration Results, Mineral Resource and Ore Reserve (The JORC Code, 2004 edition), and also conform to the standards set out in the South African Code for the Reporting of Exploration Results, Mineral Resources and Mineral Reserves (The SAMREC Code, 2007 edition). The Mineral Resource is inclusive of the Ore Reserve component unless otherwise stated. AngloGold Ashanti has in place all the necessary statutory mining authorisations and permits in the jurisdictions where it operates to mine for, or explore for, declared materials, or has a reasonable expectation of such mining authorisations and permits being granted.

AngloGold Ashanti strives to actively create value by growing its major asset – the Mineral Resource and Ore Reserve. This drive is based on an active, well-defined brownfields exploration programme, innovation in both geological modelling and mine planning, and continual optimisation of its asset portfolio.

Mineral Resource

The total Mineral Resource increased from 220.0Moz in December 2010 to 230.9Moz in December 2011. A gross annual increase of 16.8Moz occurred before depletion and while the net increase after allowing for depletion was 10.9Moz, changes in economic assumptions from December 2010 to December 2011 resulted in an 11.2Moz increase to the Mineral Resource, while exploration and modelling resulted in an increase of 7.9Moz. The remaining decrease of 2.2Moz resulted from various other factors. Depletion from the Mineral Resource for the year totalled 6.0Moz. The Mineral Resource was estimated at a gold price of $1,600/oz (2010: $1,100/oz).

Ore Reserve

The AngloGold Ashanti Ore Reserve increased from 71.2Moz in December 2010 to 75.6Moz in December 2011. A gross annual increase of 9.6Moz occurred before depletion of 5.2Moz. The increase net of depletion was therefore 4.4Moz. Changes in economic assumptions from 2010 to 2011 resulted in an increase of 4.4Moz to the Ore Reserve, while exploration and modelling resulted in a further increase of 5.0Moz. The remaining increase of 0.2Moz resulted from various other factors.

The Ore Reserve was calculated using a gold price of $1,100/oz (2010: $850/oz).

By-products

Several by-products are recovered as a result of the processing of the gold Ore Reserve. In 2011, the by-product Ore Reserve included 57,299t of uranium oxide from the South African operations, 408,348t of sulphuric acid from Brazil and 46.9Moz of silver from Argentina.

Competent persons

The information in this report relating to exploration results, Mineral Resource and Ore Reserve is based on information compiled by the Competent Persons. The Competent Persons consent to the inclusion of exploration results, Mineral Resource and Ore Reserve information in this report, in the form and context in which it appears.

During the past decade, the company has developed and implemented a rigorous system of internal and external reviews of exploration results, Mineral Resource and Ore Reserve. A documented chain of responsibility exists from the Competent Persons at the operations to the company's Mineral Resource and Ore Reserve Steering Committee. Accordingly, the chairman of the Mineral Resource and Ore Reserve Steering Committee, VA Chamberlain, MSc (Mining Engineering), BSc (Hons) (Geology), MGSSA, FAusIMM, assumes responsibility for the Mineral Resource and Ore Reserve processes for AngloGold Ashanti and is satisfied that the Competent Persons have fulfilled their responsibilities. Mr Chamberlain can be contacted at 76 Jeppe Street, Newtown, 2001, South Africa.

A more detailed breakdown of AngloGold Ashanti‘s Mineral Resource and Ore Reserve is provided in the Mineral Resource and Ore Reserve Report 2011Mineral Resource and Ore Reserve Report 2011 (PDF - 3.91MB).

 
Mineral Resource   Moz
Mineral Resource as at 31 December 2010   220.0
Reductions    
Great Noligwa Mineral Resource reduced due to increased costs (0.6)
Other Total of non-significant changes (1.8)
Additions    
Tropicana Exploration success in the underground project 0.8
Gramalote Exploration success at Trinidad 0.9
Kopanang Grade increased as a result of exploration 1.1
Geita Combined effect of price and estimation 1.3
Iduapriem Improved Mineral Resource price 1.3
Obuasi Improved Mineral Resource price 2.3
La Colosa Exploration success 3.8
Other Total of non-significant changes 1.7
Mineral Resource as at 31 December 2011   230.9
 
Ore Reserve   Moz
Ore Reserve as at 31 December 2010   71.2
Reductions    
Moab Khotsong Depletion and minor model revision (0.5)
Other Total of non-significant changes (1.1)
Additions    
Geita Improved Ore Reserve price 0.5
Cripple Creek & Victor Mine life extension added to Ore Reserve 0.5
Vaal River surface operations Technical studies showed that the economic extraction
of gold and uranium from the tailings is viable
3.2
Other Total of non-significant changes 1.7
Ore Reserve as at 31 December 2011   75.6

Rounding of numbers may result in computational discrepancies.

Inclusive Mineral Resource by country – attributable
Contained gold
As at 31 December 2011 Category Tonnes million Grade g/t Tonnes Moz
South Africa Measured 25.98 15.76 409.39 13.16
  Indicated 799.63 2.57 2,056.44 66.12
  Inferred 38.30 14.91 570.81 18.35
  Total 863.91 3.52 3,036.65 97.63
Democratic Republic of the Congo Measured
  Indicated 62.41 3.66 228.64 7.35
  Inferred 33.16 2.90 96.07 3.09
  Total 95.57 3.40 324.71 10.44
Ghana Measured 89.38 4.64 414.35 13.32
  Indicated 97.81 3.42 334.74 10.76
  Inferred 136.86 3.26 446.65 14.36
  Total 324.04 3.69 1,195.74 38.44
Guinea Measured 37.19 0.62 22.96 0.74
  Indicated 116.48 0.73 85.09 2.74
  Inferred 67.18 0.79 53.17 1.71
  Total 220.85 0.73 161.22 5.18
Mali Measured 12.65 1.31 16.57 0.53
  Indicated 62.66 1.57 98.24 3.16
  Inferred 36.58 1.04 37.96 1.22
  Total 111.89 1.37 152.77 4.91
Namibia Measured 18.35 0.71 13.10 0.42
  Indicated 99.78 1.22 122.04 3.92
  Inferred 16.41 1.15 18.88 0.61
  Total 134.54 1.14 154.01 4.95
Tanzania Measured
  Indicated 106.42 2.74 291.44 9.37
  Inferred 33.55 2.97 99.50 3.20
  Total 139.96 2.79 390.94 12.57
Australia Measured 35.13 1.71 60.01 1.93
  Indicated 50.11 2.56 128.48 4.13
  Inferred 11.05 3.92 43.28 1.39
  Total 96.29 2.41 231.77 7.45
Argentina Measured 11.98 1.61 19.30 0.62
  Indicated 26.09 3.40 88.76 2.85
  Inferred 9.14 3.17 29.01 0.93
  Total 47.22 2.90 137.08 4.41
Brazil Measured 10.53 6.31 66.44 2.14
  Indicated 16.41 5.74 94.23 3.03
  Inferred 36.93 6.30 232.73 7.48
  Total 63.88 6.16 393.40 12.65
Colombia Measured 15.56 0.85 13.24 0.43
  Indicated 33.97 0.79 26.98 0.87
  Inferred 564.78 0.93 527.63 16.96
  Total 614.31 0.92 567.85 18.26
United States Measured 280.58 0.78 217.65 7.00
  Indicated 227.03 0.68 155.09 4.99
  Inferred 96.04 0.65 62.16 2.00
  Total 603.65 0.72 434.90 13.98
Total Measured 537.33 2.33 1,253.01 40.29
  Indicated 1,698.79 2.18 3,710.18 119.29
  Inferred 1,079.98 2.05 2,217.85 71.31
  Total 3,316.10 2.17 7,181.04 230.88

Rounding of numbers may result in computational discrepancies

Exclusive Mineral Resource by country – attributable
Contained gold
As at 31 December 2011 Category Tonnes million Grade g/t Tonnes Moz
South Africa Measured 15.36 16.99 261.03 8.39
  Indicated 230.15 4.01 923.55 29.69
  Inferred 16.98 21.15 358.97 11.54
  Total 262.49 5.88 1,543.56 49.63
Democratic Republic of the Congo Measured
  Indicated 28.97 3.04 87.97 2.83
  Inferred 33.16 2.90 96.07 3.09
  Total 62.13 2.96 184.03 5.92
Ghana Measured 20.74 5.15 106.80 3.43
  Indicated 64.26 3.63 233.54 7.51
  Inferred 136.67 3.27 446.64 14.36
  Total 221.66 3.55 786.98 25.30
Guinea Measured 0.83 0.54 0.45 0.01
  Indicated 41.37 0.74 30.64 0.99
  Inferred 67.18 0.79 53.17 1.71
  Total 109.39 0.77 84.26 2.71
Mali Measured 4.73 0.86 4.09 0.13
  Indicated 31.26 1.26 39.43 1.27
  Inferred 36.58 1.04 37.96 1.22
  Total 72.57 1.12 81.48 2.62
Namibia Measured 7.57 0.53 4.01 0.13
  Indicated 53.86 1.06 56.88 1.83
  Inferred 16.41 1.15 18.88 0.61
  Total 77.85 1.02 79.77 2.56
Tanzania Measured
  Indicated 50.59 2.84 143.72 4.62
  Inferred 33.55 2.97 99.50 3.20
  Total 84.14 2.89 243.22 7.82
Australia Measured 2.27 0.58 1.32 0.04
  Indicated 18.02 2.78 50.18 1.61
  Inferred 10.72 3.99 42.78 1.38
  Total 31.02 3.04 94.28 3.03
Argentina Measured 2.80 2.08 5.81 0.19
  Indicated 22.22 2.13 47.28 1.52
  Inferred 9.14 3.17 29.01 0.93
  Total 34.16 2.40 82.11 2.64
Brazil Measured 2.86 7.39 21.13 0.68
  Indicated 7.02 6.53 45.82 1.47
  Inferred 35.80 6.37 228.05 7.33
  Total 45.67 6.46 295.00 9.48
Colombia Measured 15.56 0.85 13.24 0.43
  Indicated 33.97 0.79 26.98 0.87
  Inferred 564.78 0.93 527.63 16.96
  Total 614.31 0.92 567.85 18.26
United States Measured 119.80 0.71 85.17 2.74
  Indicated 140.43 0.66 93.03 2.99
  Inferred 82.15 0.66 54.08 1.74
  Total 342.39 0.68 232.28 7.47
Total Measured 192.52 2.61 503.06 16.17
  Indicated 722.13 2.46 1,779.02 57.20
  Inferred 1,043.12 1.91 1,992.74 64.07
  Total 1,957.76 2.18 4,274.82 137.44

Rounding of numbers may result in computational discrepancies

Ore Reserve by country – attributable
Contained gold
As at 31 December 2011 Category Tonnes million Grade g/t Tonnes Moz
South Africa Proved 11.89 8.85 105.17 3.38
  Probable 573.65 1.57 903.41 29.05
  Total 585.54 1.72 1,008.58 32.43
Democratic Republic of the Congo Proved
  Probable 33.44 4.21 140.69 4.52
  Total 33.44 4.21 140.69 4.52
Ghana Proved 42.73 3.08 131.77 4.24
  Probable 53.94 4.43 239.06 7.69
  Total 96.67 3.84 370.83 11.92
Guinea Proved 35.72 0.61 21.90 0.70
  Probable 72.18 0.69 49.97 1.61
  Total 107.90 0.67 71.87 2.31
Mali Proved 5.20 1.91 9.93 0.32
  Probable 43.13 1.56 67.20 2.16
  Total 48.33 1.60 77.13 2.48
Namibia Proved 6.31 1.09 6.88 0.22
  Probable 44.18 1.29 56.88 1.83
  Total 50.49 1.26 63.76 2.05
Tanzania Proved
  Probable 55.81 2.64 147.11 4.73
  Total 55.81 2.64 147.11 4.73
Australia Proved 32.86 1.79 58.69 1.89
  Probable 28.98 2.55 73.95 2.38
  Total 61.84 2.14 132.64 4.26
Argentina Proved 10.56 1.35 14.30 0.46
  Probable 12.85 4.25 54.64 1.76
  Total 23.41 2.95 68.94 2.22
Brazil Proved 7.01 5.51 38.65 1.24
  Probable 7.84 4.68 36.65 1.18
  Total 14.85 5.07 75.30 2.42
Colombia Proved 160.78 0.82 132.48 4.26
  Probable 86.60 0.72 62.06 2.00
  Total 247.38 0.79 194.54 6.25
Total Proved 313.07 1.66 519.78 16.71
  Probable 1,012.60 1.81 1,831.63 58.89
  Total 1,325.67 1.77 2,351.40 75.60

Rounding of numbers may result in computational discrepancies