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Annual report suite 2012

MINERAL RESOURCE AND ORE RESERVE

– Summary

We at AngloGold Ashanti continue to actively drive the creation of value by continually growing our Mineral Resource and Ore Reserve.

The AngloGold Ashanti Mineral Resource and Ore Reserve are reported in accordance with the minimum standards described by the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (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). Mineral Resource is inclusive of the Ore Reserve component unless otherwise stated.

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 230.9Moz in December 2011 to 241.5Moz in December 2012. A gross annual increase of 15.8Moz occurred before depletion while the net increase, after allowing for depletion, is 10.7Moz. Changes in economic assumptions from December 2011 to December 2012 resulted in a 1.2Moz increase to the Mineral Resource, whilst exploration and modelling resulted in an increase of 14.4Moz. Depletion from the Mineral Resource for the year totalled 5.1Moz. The acquisition of the remaining 50% of Serra Grande and the purchase of Mine Waste Solutions added a total of 3.8Moz to the Mineral Resource. A decrease of 3.7Moz resulted from various other factors.

The Mineral Resource has been estimated at a gold price of $2,000/oz (2011: $1,600/oz).

Inclusive Mineral Resource
Moz
Mineral Resource as at 31 December 2011   230.9
Reductions    
Great Noligwa Revisions due to reduced likelihood of eventual extraction (2.8)
Obuasi Revised estimates of historic mining (2.0)
CC&V Combination of increased costs and revised metallurgical recoveries (1.1)
Kopanang Negative exploration results and depletion (1.0)
Other Total of non-significant changes (1.9)
Additions    
Tropicana Reporting of Havana as an open pit Mineral Resource 1.0
Mponeng Revised geological modelling of the Ventersdorp Contact Reef 1.3
La Colosa Exploration success 10.6
Other Total of non-significant changes 2.6
Acquisitions    
Serra Grande Acquisition of the remaining 50% of the operation 1.2
Mine Waste Solutions Acquisition of Mine Waste Solutions 2.7
Mineral Resource as at 31 December 2012   241.5
  1. Rounding of figures may result in computational discrepancies.

ORE RESERVE

The AngloGold Ashanti Ore Reserve declined from 75.6Moz in December 2011 to 74.1Moz in December 2012. A gross annual increase of 3.2Moz occurred before depletion of 4.7Moz. The decrease net of depletion was therefore 1.5Moz. Changes in economic assumptions from 2011 to 2012 resulted in a reduction of 0.6Moz to the Ore Reserve, while exploration and modelling resulted in an increase of 0.6Moz. The acquisition of the remaining 50% of Serra Grande and Mine Waste Solutions added a further 2.8Moz. The remaining increase of 0.4Moz resulted from various other factors.

The Ore Reserve has been calculated using a gold price of $1,300/oz (2011: $1,100/oz).

Ore Reserve
Moz
Ore Reserve as at 31 December 2011   75.6
Reductions    
Kopanang Depletion and minor model revision (1.4)
Obuasi Revised mine planning parameters and geotechnical review (0.9)
Great Noligwa Economic driven reduction of underground mining footprint (0.7)
Other Total non-significant changes (2.7)
Additions    
Kibali Open pit increase due to additional metal defined by grade control drilling 0.4
Geita Positive economic changes 0.7
Other Total of non-significant changes 0.3
Acquisitions    
Serra Grande Purchase of remaining 50% of the operation 0.4
Mine Waste Solutions Purchase of Mine Waste Solutions 2.4
Ore Reserve as at 31 December 2012   74.1
  1. Rounding of figures may result in computational discrepancies.

By-products

Several by-products are recovered as a result of the processing of gold Ore Reserve. These include 73,492t of uranium oxide from the South African operations, 439,564t of sulphur from Brazil and 40.7Moz 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.

RR A detailed breakdown of Mineral Resource and Ore Reserve and backup detail is provided on a seperate report available for download.

Mineral Resource by country (attributable) inclusive of Ore Reserve
as at 31 December 2012 Category Tonnes
million
Grade
g/t
Contained gold
Tonnes Moz
South Africa
South Africa Measured 183.97 2.33 428.52 13.78
Indicated 964.52 2.16 2,080.80 66.90
Inferred 53.34 10.45 557.39 17.92
Total 1,201.83 2.55 3,066.71 98.60
Continental Africa
Democratic Republic of the Congo Measured 1.97 3.00 5.89 0.19
Indicated 63.18 3.70 233.93 7.52
Inferred 30.43 2.91 88.69 2.85
Total 95.58 3.44 328.51 10.56
Ghana Measured 64.84 4.63 300.44 9.66
Indicated 103.86 3.87 401.45 12.91
Inferred 150.37 2.87 431.63 13.88
Total 319.07 3.55 1,133.52 36.44
Guinea Measured 38.45 0.63 24.15 0.78
Indicated 125.81 0.72 90.37 2.91
Inferred 56.71 0.82 46.32 1.49
Total 220.97 0.73 160.84 5.17
Mali Measured 9.16 0.94 8.63 0.28
Indicated 52.02 1.81 94.30 3.03
Inferred 27.75 0.94 26.00 0.84
Total 88.93 1.45 128.93 4.15
Namibia Measured 17.21 0.64 11.03 0.35
Indicated 96.58 1.22 117.73 3.79
Inferred 7.76 1.08 8.36 0.27
Total 121.55 1.13 137.12 4.41
Tanzania Measured
Indicated 103.81 2.63 273.00 8.78
Inferred 39.21 2.78 109.00 3.50
Total 143.02 2.67 382.00 12.28
Australasia
Australia Measured 36.46 1.70 62.00 1.99
Indicated 71.84 2.10 150.68 4.84
Inferred 14.98 3.13 46.82 1.51
  Total 123.28 2.10 259.50 8.34
Americas        
Argentina Measured 11.60 1.59 18.48 0.59
Indicated 36.91 2.87 105.90 3.40
Inferred 7.49 2.98 22.34 0.72
Total 56.00 2.62 146.72 4.72
Brazil Measured 14.52 5.81 84.40 2.71
Indicated 21.01 5.31 111.51 3.59
Inferred 48.74 5.29 257.63 8.28
Total 84.27 5.38 453.54 14.58
Colombia Measured 15.68 0.85 13.30 0.43
Indicated 34.36 0.79 27.21 0.87
Inferred 1,025.23 0.85 873.63 28.09
Total 1,075.27 0.85 914.14 29.39
United States Measured 267.56 0.77 207.24 6.66
Indicated 208.89 0.67 140.04 4.50
Inferred 84.56 0.64 53.87 1.73
Total 561.01 0.72 401.15 12.90
Total Measured 661.42 1.76 1,164.08 37.43
Indicated 1,882.79 2.03 3,826.92 123.04
Inferred 1,546.58 1.63 2,521.68 81.07
Total 4,090.79 1.84 7,512.68 241.54
  1. Rounding of figures may result in computational discrepancies.
Mineral Resource by country (attributable) exclusive of Ore Reserve
as at 31 December 2012 Category Tonnes
million
Grade
g/t
Contained gold
Tonnes Moz
South Africa
South Africa Measured 16.52 18.23 301.15 9.68
Indicated 249.09 4.56 1,136.02 36.52
Inferred 27.64 8.79 242.82 7.81
Total 293.25 5.73 1,679.99 54.01
Continental Africa
Democratic Republic of the Congo Measured 0.37 1.85 0.68 0.02
Indicated 28.38 3.24 91.92 2.96
Inferred 30.43 2.91 88.69 2.85
Total 59.18 3.06 181.29 5.83
Ghana Measured 21.63 7.16 154.96 4.98
Indicated 48.49 3.50 169.84 5.46
Inferred 150.35 2.86 429.66 13.81
Total 220.47 3.42 754.46 24.26
Guinea Measured 1.03 0.52 0.54 0.02
Indicated 55.92 0.73 40.74 1.31
Inferred 56.71 0.82 46.32 1.49
Total 113.66 0.77 87.60 2.82
Mali Measured 5.22 0.73 3.82 0.12
Indicated 23.92 1.50 35.79 1.15
Inferred 27.75 0.94 26.00 0.84
Total 56.89 1.15 65.61 2.11
Namibia Measured 5.89 0.53 3.12 0.10
Indicated 56.10 1.07 60.17 1.93
Inferred 7.76 1.08 8.36 0.27
Total 69.75 1.03 71.65 2.30
Tanzania Measured
Indicated 42.97 2.68 115.34 3.71
Inferred 35.95 2.74 98.59 3.17
Total 78.92 2.71 213.93 6.88
Australasia
Australia Measured 3.33 1.14 3.80 0.12
Indicated 45.02 1.94 87.13 2.80
Inferred 14.98 3.13 46.82 1.51
Total 63.33 2.18 137.75 4.43
Americas
Argentina Measured 2.14 2.55 5.45 0.18
Indicated 31.31 1.69 52.91 1.70
Inferred 7.49 2.98 22.34 0.72
Total 40.94 1.97 80.70 2.59
Brazil Measured 4.98 6.25 31.14 1.00
Indicated 10.36 4.91 50.89 1.64
Inferred 48.40 5.30 256.36 8.24
Total 63.74 5.31 338.39 10.88
Colombia Measured 15.68 0.85 13.30 0.43
Indicated 34.36 0.79 27.21 0.87
Inferred 1,025.23 0.85 873.63 28.09
Total 1,075.27 0.85 914.14 29.39
United States Measured 112.75 0.72 81.08 2.61
Indicated 126.54 0.66 83.21 2.68
Inferred 84.56 0.64 53.87 1.73
Total 323.85 0.67 218.16 7.01
Total Measured 189.54 3.16 599.05 19.26
Indicated 752.46 2.59 1,951.16 62.73
Inferred 1,517.27 1.45 2,193.45 70.52
Total 2,459.27 1.93 4,743.66 152.51
  1. Rounding of figures may result in computational discrepancies.
Ore Reserve by country (attributable)
as at 31 December 2012 Category Tonnes
million
Grade
g/t
Contained gold
Tonnes Moz
South Africa
South Africa Proved 148.71 0.66 98.04 3.15
Probable 728.45 1.21 883.59 28.41
Total 877.16 1.12 981.63 31.56
Continental Africa
Democratic Republic of the Congo Proved 1.59 3.26 5.20 0.17
Probable 35.90 4.12 147.84 4.75
Total 37.49 4.08 153.04 4.92
Ghana Proved 40.88 3.42 139.66 4.49
Probable 52.77 3.67 193.84 6.23
Total 93.65 3.56 333.50 10.72
Guinea Proved 36.59 0.63 22.92 0.74
Probable 67.60 0.67 45.56 1.46
Total 104.19 0.66 68.48 2.20
Mali Proved 2.26 1.30 2.93 0.09
Probable 36.61 1.81 66.32 2.13
Total 38.87 1.78 69.25 2.23
Namibia Proved
Probable 51.80 1.26 65.29 2.10
Total 51.80 1.26 65.29 2.10
Tanzania Proved
Probable 65.06 2.59 168.63 5.42
Total 65.06 2.59 168.63 5.42
Australasia
Australia Proved 33.13 1.76 58.20 1.87
Probable 26.82 2.37 63.55 2.04
Total 59.95 2.03 121.75 3.91
Americas
Argentina Proved 10.44 1.29 13.49 0.43
Probable 10.90 4.56 49.71 1.60
Total 21.34 2.96 63.20 2.03
Brazil Proved 9.29 4.47 41.51 1.33
Probable 12.48 4.39 54.74 1.76
Total 21.77 4.42 96.25 3.09
United States of America Proved 154.81 0.81 126.16 4.06
Probable 82.35 0.69 56.83 1.83
Total 237.16 0.7 182.99 5.88
Total Proved 437.72 1.16 508.11 16.34
Probable 1,170.74 1.53 1,795.90 57.74
Total 1,608.46 1.43 2,304.01 74.08
  1. Rounding of figures may result in computational discrepancies.