

Total exploration expenditure in 2008 amounted to $183 million, of which $77 million was spent on greenfield exploration, $86 million on brownfield exploration and the balance of $20 million on pre-feasibility studies. The main aim of both the greenfield and brownfield exploration programmes is to identify new attributable resource ounces of gold.
Greenfield exploration activities were undertaken in six countries Australia, China, Colombia, the Democratic Republic of Congo (DRC), the Philippines and Russia during 2008. A total of 304,371 metres of diamond, reverse circulation, and aircore drilling was completed in testing existing priority targets and in the delineation of new targets in Australia, Colombia, Russia, the DRC and China (refer to figure below).
Greenfield activities in Russia, China and the Philippines were undertaken predominantly through joint ventures and strategic alliances. While the discovery of new long-life, low-cost mines remains the principal aim of the greenfield exploration programme, AngloGold Ashanti is also committed to maximising shareholder value by divesting those exploration assets that do not meet its internal growth criteria and by opportunistically investing in prospective junior exploration companies.

* including pre-feasibilty study
Exploration in the Philippines was less than 1%.

During the year to 31 December 2008, a total of 13.26 million attributable ounces of Measured, Inferred and Indicated Mineral Resources were defined and announced by AngloGold Ashanti's greenfield exploration teams at two prospects Tropicana (Western Australia) and La Colosa (Colombia).
| Country | Key project | AngloGold Ashanti Equity (%) | Joint venture partner (%) | 2008 Additional resources (Moz of Au) | Grade (g/t Au) |
|---|---|---|---|---|---|
| Colombia | La Colosa | 100 | | 12.3* | 1.00 |
| Australia | Tropicana/Havana | 70 | Independence | ||
| Group (30) | 0.96* | 2.07 | |||
| Total | 13.26 |
*At a gold price of $1,000/oz
In the last three years the average discovery cost per ounce of greenfield exploration was $10. At La Colosa, specifically in 2007 and 2008, the discovery cost per additional ounce of gold was $1.
In 2009, exploration expenditure of some $146 million is planned, with $90 million of this budgeted to be spent on greenfield exploration with the remaining $56 million allocated to a pre-feasibility study at La Colosa in Colombia.
Drilling and resource modelling at La Colosa has rapidly defined a gold porphyry system with a grade of more than 0.3 g/t Au extending over a strike length in excess of 1,500 metres and a width of 600 metres, which has defined an Inferred Mineral Resource of 381.4Mt @ 1.00g/t Au for 12.3 million ounces of gold at a gold price of $1,000/oz and a lower cut-off of 0.3g/t Au.
| Cut-off grade (g/t Au) | Tonnes (Mt) | Grade (g/t Au) | Contained Metal (kg Au) | Au (Moz) |
|---|---|---|---|---|
| 0.3 | 381.4 | 1.00 | 383,116 | 12.3 |
| 0.4 | 363.8 | 1.04 | 377,225 | 12.1 |
| 0.5 | 343.5 | 1.07 | 368,040 | 11.8 |
Based on present drilling and geochemical observations, the La Colosa mineralisation systems, including the La Belgica sector, remain open to the north, south and east. Various additional targets immediately surround the known La Colosa mineralisation. This is the first significant gold porphyry discovery in the Colombian Andes, where AngloGold Ashanti has first mover advantage with granted and application tenements covering an area of some 61,700 square kilometres, with significant potential to increase the Mineral Resource at La Colosa and at other projects.
The La Colosa drill programme was suspended in late February 2008 in order to comply with unexpected environmental requirements. All of the necessary documentation has been submitted to the relevant authorities for approval.
AngloGold Ashanti and its partners actively explored for precious and base metal deposits. In all, 294 targets were generated by systematic exploration in an area covering 4.2 million hectares, on 408 mineral tenement contracts, joint venture partner B2Gold Corp. continued resource delineation drilling at Gramalote, first phase drilling at Quebradona and continued reconnaissance and drill target definition work in three departments in Colombia. Mineros S.A. drilled one target in Antioquia and conducted reconnaissance and drill target definition work at two other targets within the Segovia joint venture in the Antioquia department. Significant results were released from the Quebradona gold-copper porphyry project that are likely to increase the Mineral Resource at this project.
On receipt of all assay and geological data for the AngloGold Ashanti/B2Gold JV Quebradona drilling programme, AngloGold Ashanti has a period of 30 days in which to decide on its level of future participation in the project (49%, 51% or 65% interest). Glencore International remained focused on early stage exploration and conducted airborne geophysical surveys within joint venture areas.
AngloGold Ashanti activities during the year also included flying in-house airborne magnetometry and radiometric surveys for a total of 11,463 line kilometres.
Exploration activities undertaken on the 10,000 square kilometre Concession 40 (AngloGold Ashanti 86.22% and OKIMO 13.78%) mineral claim that encompasses most of the Kilo greenstone belt and which remains largely unexplored by modern methods, included both regional work and additional drilling at and around the Mongbwalu resource. Around Mongbwalu, detailed surface mapping and data integration are enhancing understanding of the immediate area's potential. At the Issuru prospect, located approximately 4 kilometres north of Mongbwalu, drilling defined potential economic mineralisation over a strike length of approximately 800 metres and a width of up to 450 metres.
Regional exploration activities focused around four main areas including Lodjo, Bunia West, Mount Tsi and Petsi, all of which are located within 50 kilometres of the Mongbwalu resource area. Field work concentrated on detailed mapping, soil sampling and trenching. Encouraging results were obtained from trench sampling at Lodjo. At the Petsi prospect, a ≤ 30 metres wide potentially gold mineralised shear zone has been identified by trenching over a distance of 1.8 kilometres. Results from infill soil sampling define an anomaly approximately 450 metres wide and 300 metres long. Regional aeromagnetic (5,550 square kilometres) and aerial EM surveys (1,224 square kilometres) were completed. Results of these surveys, combined with those from the regional geochemistry programmes, will provide the platform from which to fast-track regional exploration over the concession.
The findings of the DRC Minerals Review Commission have resulted in AngloGold Ashanti and the AGK joint venture engaging the DRC government to seek resolution and secure the rights to Concession 40. Exploration activities over the Concession 40 licence were suspended in November 2008 following the deteriorating security situation which led to the precautionary withdrawal of most non-essential staff from the concession.
The formation of Zoloto Taigi, the AngloGold Ashanti/Polymetal strategic alliance vehicle was completed. It is anticipated that this strategic alliance will enable AngloGold Ashanti to increase its presence in Russia by pursuing new opportunities by participating in licence auctions, acquiring equity in prospective projects and by project generation in new or less intensely explored areas. Exploration work to increase and upgrade the resource economics at Veduga was undertaken. Trenching and drilling at this advanced project have demonstrated strike continuation of mineralisation from the south-eastern ore zone for a further 500 metres along strike. At the recently acquired Penchenga property, regional soil geochemistry has begun. The Bogunay project (42 square kilometres) was sold while negotiations on the sale of Anenskoye (11.8 square kilometres) and Aprelkovskoye (161 square kilometres) continue.
During 2008, greenfield activities in Africa concentrated on project reviews and regional target generation work in west, central and east Africa. The intention is to increase the level of greenfield exploration in Africa over the next two years.
Final approval of the Mapawa Mineral Production Sharing Agreement (MPSA) is awaited from the Department of Environment and Natural Resources (DENR) in Manila. Elsewhere in south-east Asia specific project reviews and project generation work continue.
In China, AngloGold Ashanti operates three co-operative joint ventures (CJVs) with local partners at Yili-Yunlong (Xinjiang Province), Jinchanggou (Gansu Province) and Pingwu (Sichuan Province). During 2008, AngloGold Ashanti withdrew from the Pingwu CJV at the time of the devastating Sichuan earthquake.
At the Jinchanggou CJV Project (Gansu Province), soil sampling on the eastern and western tenements indicated significant extensions to known mineralisation with anomalous gold-in-soils over more than a 16 kilometre strike length. Final approval for the Jinchanggou CJV was received from the Gansu government in late June. A subsequent programme of diamond drilling and trenching designed to test the 16 kilometre long gold-in-soil anomaly was completed at the Jinchanggou project in December. Despite intersecting significant intervals of intense alteration and shearing in drilling, analytical results were disappointing.
Results from the diamond drilling programme completed in 2007 to test a conceptual porphyry target on the tenements held by the Yili - Yunlong CJV (Xinjiang Province) returned low gold and copper results. Results of follow-up work on other targets defined by soil sampling and geological mapping, and the investigation of geochemical anomalies coincident with silica-clay alteration, has led to the prospectivity of the area being downgraded.
An intense phase of project generation undertaken in China in 2008 resulted in tenement applications being lodged in three provinces of China; Xinjiang, Inner Mongolia and Heilongjiang.
In mid 2008, exploration at the Tropicana joint venture (AngloGold Ashanti 70%, Independence Group 30%) moved from a focus on resource drilling of the Tropicana-Havana deposit within the Tropicana Gold Project, to initial testing of targets within potential trucking distance of the planned operation. A large number of discrete targets have been identified within a 50-60 kilometre radius of the proposed plant site (see map).
Field mapping and rock chip sampling at the Black Dragon and Voodoo Child prospects identified outcropping gold mineralisation. Analysis of rock chip sampling from Black Dragon returned high-grade gold and silver results. Subsequent reverse circulation drilling has not explained these surface results. A large geochemical gold anomaly (3 kilometre by 1 kilometre) has been defined at the Kamikaze prospect with encouraging results at the Tumbleweed prospect situated to the north of the resource area. Reverse circulation drilling returned significant results from several other prospects including Rusty Nail and Screaming Lizard.
Initial diamond drilling at Beachcomber, approximately 200 kilometres to the south and within the Tropicana joint venture area, intersected quartz veining with visible gold.
In addition to the Tropicana joint venture area, which totals approximately 12,500 square kilometres, AngloGold Ashanti holds 100% of a substantial land package (~6,764 square kilometres) in the Viking area. Most of the tenements in the Viking project are recent applications, with some tenements having been granted in late 2008. Field activities will begin in 2009.
The recently acquired Bronco Plains joint venture (AngloGold Ashanti earning 50.4%), hosts an approximately 10 kilometre-long gold-in-soil anomaly peaking at 86 ppb gold. In terms of the joint venture agreement with Image Resources, AngloGold Ashanti and Independence Group can earn a combined 72% interest in the project by spending $2 million.
The Tropicana joint venture, Bronco Plains joint venture and the Viking project cover a total distance of 600 kilometres along the margin of the Yilgarn Craton. The 5 million ounce Tropicana discovery, numerous prospects identified by AngloGold Ashanti and promising results reported by other explorers give credence to the Tropicana belt being a strike-extensive new gold province.
Brownfields exploration, aimed at identifying replacement ounces for production, was undertaken around the globe at most current operations- with the most success being in South Africa, Australia, Ghana and Guinea.
The brownfields exploration programme for 2008 was aimed at replacing ounces at current operations and successfully added a total of 27.5 million ounces to the company's Mineral Resource.
At Cerro Vanguardia, reconnaissance drilling continued with 45 kilometres of veins being explored via 454 reverse circulation (RC) holes. This drilling identified 17 veins for infill drilling in 2009. While infill drilling (8,075 metres RC and 11,457.5 metres diamond drilling) extended some of the current ore shoots and added 0.28 million ounces of gold and 7.9 million ounces of silver to the Mineral Resource.
During the year, a hyperspectral survey was completed over the lease area. A new area, El Volcán, was permitted in 2008 and initial exploration activities have commenced. Deep level drilling (+300 metres) to explore the depths of current veins for underground potential began during the year. Initial results are encouraging.
At Sunrise Dam, exploration focused on increasing the underground gold Mineral Resource to enable increased production in 2009 and 2010 while defining long-term zones of gold mineralisation up to 1.25 kilometre vertically below the mine. Additionally, short-term opportunities for satellite open pits within the immediate mine area were also investigated. During the period 41,417 metres of diamond core was drilled from 297 drill holes with 8,873.1 metres drilled into the deep targets.
At Boddington Gold Mine, a maximum of five diamond drill rigs were employed during the year to complete a total of 101,700 metres of drilling in 141 holes targeting in-pit Mineral Resource conversion and near-pit Mineral Resource extensions. By the end of 2008, attributable Ore Reserves were increased by 1.1 million ounces to 6.7 million ounces and Mineral Resources increased by 1.6 million ounces to 11.9 million ounces of contained gold. Subsequent to year-end, AngloGold Ashanti disposed of its interest in Boddington to Newmont.
At Córrego do Sítio, drilling of underground deposits continued. A total of 37,865 metres were drilled from surface and 10,142 metres from underground during 2008. Furthermore 3,482 metres of underground development, of which 1,107 metres were on reef, was completed. Drilling concentrated on the Carvoaria, Laranjeiras and the Cachorro Bravo orebodies. Minor drilling (2,491 metres) was completed on surface oxide deposits. At Lamego, a total of 22,782 metres were drilled from surface and 17,632 metres from underground. Furthermore a total of 4,063 metres of underground development, of which 1,428 metres were on reef, was completed. The drilling consisted of a combination of intermediate depth surface drilling targeted at the extensions of the Cabeca de Pedra and Arco da Velha orebodies, underground extension drilling of Queimada and surface and underground infill drilling at Carruagem.
On 10 December 2008, the purchase of the São Bento mine was completed. This area will be the focus of significant exploration in 2009.
At Serra Grande, the main targets for 2008 were Pequizão and Palmeiras. A total of 37,000 metres of diamond drilling was completed.
At Obuasi, drilling for the Deeps project below 50 level continued with the areas below KMS and Adansi Shafts being targeted from 50 level. Active exploration continued above 50 Level.
At Iduapriem, drilling for the year consisted of Mineral Resource conversion drilling at Ajopa with a combination of RC (10,765 metres) and diamond drilling 3,127 metres). The programme was completed in December and sampling and logging of the diamond core is currently being completed.
At Siguiri, early stage exploration in the form of gridded geochemical sampling was conducted in Block 1 (Eureka North Kantinian corridor and Sintroko South), Block 2 (Manguity and Saraya South), the Naboun Block (28 kilometres north of the mine) and the Corridor Block (11 kilometres from the mine). Reconnaissance air core drilling was undertaken at Satiguia, Manguity (35 kilometres west of the mine), Kouremale (Block 4) and Kolita-Kounkoun (Block 3). Mineral Resource Delineation drilling was conducted at Saraya (55 kilometres west of the mine). Mineral Resource conversion drilling was completed at Sintroko South (8 kilometres south of the mine) and added 0.7 million ounces to the Mineral Resource and allowed for the conversion of 0.7 million ounces to Ore Reserve. Infill drilling was completed on the margins of the Séguélen (Kintinian) project.
A major review of the geology of Block 1 conducted during the year indicated significant upside to the mineralisation. A project which has been launched to remodel the Mineral Resource while at the same time drilling out areas of postulated strike and dip extensions to mineralisation. Initial drilling of hard rock mineralisation below the current pits has provided positive results and this drilling will continue in 2009.
At Morila, only minor field work was conducted during the year with some pitting and trenching. However a significant amount of core logging and pit mapping was completed. This led to a revised geological model, including lithological overview, tectonic setting and magmatism, being developed during the year. A revised exploration programme proposal is now under consideration.
At Sadiola, exploration work in 2008 concentrated on testing targets defined in the 2007 exploration workshop.
A total of seven targets were tested (15,978 metres air core and 5,164 metres of diamond drilling).
Phase 9 of deep sulphide drilling was carried out to the north of the main pit to test the continuity of the mineralisation intersected by previous drilling to the south. A total of 11 diamond holes were drilled (4,420 metres). This was followed by the Phase 10 drilling programme which was undertaken to collect samples for metallurgical test work. This drilling programme comprised seven long holes and 12 wedges drilled from outside the main pit, and seven short holes inside of the pit (6,118 metres).
Sulphide reconnaissance drilling (2,125 metres) was done at the FE4 pit. The programme was initiated to collect geological and structural information as well as to test for the possibility of sulphide mineralisation.
Mineral Resource delineation drilling was conducted at Lakanfla East (5,650 metres) and Sekokoto SE (1,562 metres). Mineral Resource conversion drilling was concentrated at Sekokoto Main (6,515 metres) and FE3S Gap Area (6,368 metres).
A geophysical survey ground penetration radar test (GPR) was done between FE3 and FE4 to test the efficacy of this method in predicting the thickness of the laterite cover.
At Yatela, a number of boreholes were drilled to test the continuity of the north-west extension mineralisation at depth (1,107 metres). Reconnaissance drilling (4,632 metres) at Donguera indicated some thin mineralised zones. At Dinguilou, a small Mineral Resource conversion programme was completed (3,674 metres) and the Mineral Resource definition programme was completed at year-end. Two small areas of Alamoutala were infill drilled (3,978 metres) after optimisation of the pit showed upside potential. An infill programme was completed at Niamoulama Hill late in December and results are still outstanding. A programme to explore gravity lows in the vicinity of Yatela was started and two holes (218 metres) were completed by year-end .
At Navachab, geochemical soil sampling was conducted over the footwall of the Mon Repos Thrust zone (200 samples), the Zebra target (1,762 samples) and the Ostrich and Giraffe targets. Stream sediment sampling was completed over the Okondura licence area with disappointing results. Some initial drilling was completed at the Steenbok and Starling targets. Mineral Resource conversion drilling (15,426 metres) was completed in two phases at Anomaly 16, and at Gecko 11,868 metres was drilled. Additional Mineral Resource conversion drilling (29,376 metres) was completed around the Main Pit and North Pit 2. A Spectrum electromagnetic survey was flown in November and the interpreted results are expected in early January.
Surface drilling continued in the Project Zaaiplaats area, where the target is the Vaal Reef.
A long deflection to the east is in progress in MZA9. The deflection reached a depth of some 2,941 metres when technical issues stopped the advance of the hole. The drilling contractors are trying to reopen the hole.
MMB5 is drilling in the north-west of the main Zaaiplaats block. Due to in hole problems a new deflection was started at 1,702 metres. By the end of the year, the long deflection had reached a depth of 3,172.55 metres. The Vaal Reef was not intersected as expected, due to faulting. Further deflections will be drilled in 2009.
A new hole, MGR8, was started during the year and continued with record excellent advances. By the end of the year the hole had advanced to a depth of nearly 1,596 metres.
Two surface boreholes in the Moab North area continued drilling into 2008. The targets were proposed Vaal Reef blocks in a poorly-defined, structurally complex area, north of the 'Middle Mine' area. MCY5 reached a depth of 3,129.49 metres. The Vaal Reef was not intersected, but the geological information from the hole was used to define a revised and more complex structural model.
Borehole MCY4 obtained a faulted C Reef intersection at some 2,823 metres. By year-end, the long deflection in MCY4 had reached a depth of almost 3,003 metres.
Borehole G55 at Tau Lekoa was drilled to follow-up on G54. The hole was stopped at 1,513 metres, having intersected a large fault at 1,384 metres.
At Geita, exploration activities focused on data compilation and re-interpretation, and target generation. This work was supplemented by two major geophysical airborne surveys: a high-resolution AeroTEM survey and a high-resolution airborne magnetic survey. A major exploration workshop was held on site and involved technical specialists from greenfields exploration. The outcome of this workshop was a revision to the 2009 programme.
During the year reconnaissance drilling was completed at Nyakabale West where six diamond holes were drilled (1,555 metres). At Matandani, 45 air core holes (4,080 metres) were drilled to investigate the possibility of the Matendani mineralisation being developed further to the north-west. A total of 27 reverse circulation holes (2,498 metres) were drilled on the Nyankumbu licence area.
A small follow up programme was drilled (4,015 metres) at Star and Comet after sterilisation drilling showed an anomalous intercept. No continuity of mineralisation could be determined.
At Cripple Creek & Victor in Colorado, drilling continued during the year and concentrated on the Main Cresson area, North Cresson, Schist Island, Wild Horse, Squaw Gulch and an area near the old Victor Pads. Exploration drilled a total of 85,923 metres in 416 holes.
A high-grade study which included close-spaced drilling on several targets and a selective mining test of one of the zones was started. The results were encouraging as drilling on tighter centres raised the average grade of two out of three targets and the selective mining test showed the high-grade zones could successfully be predicted, modelled, and mined.
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ANGLOGOLD ASHANTI Annual Financial Statements 2008