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INTEGRATED REPORT 2013

Above: Mooifontein tailings facility adjacent to Nasrec, Johannesburg

Reserves and resources

DRDGOLD’s attributable mineral resources decreased from 37.6Moz in FY2012 to 37.3Moz in FY2013. At the end of FY2013 attributable mineral reserves contained 1.7Moz of gold (FY2012: 1.8Moz). Normal depletions and reconciliations account for movements at the operations.

Evaluation methodology

Different methodologies are used for the evaluation of underground and surface mineral resources and mineral reserves. In the case of underground mineral resources, the sampling database is continually updated with verified sampling results. From the database, the results for each face area are put through the standard statistical and geostatistical process. Thereafter, a block model is generated and used to overlay the potential mining areas, which are then evaluated accordingly. This results in a resource being defined for each resource category. From here, the relevant modifying factors are applied and the appropriate portion converted to reserves. The whole process is reviewed by independent consultants to ensure that the accepted industry and deposit-type norms and procedures have been followed.

With respect to surface mineral resources and mineral reserves, drilling takes place on a predetermined grid to ascertain the average grade (grade model), density, moisture, mineral composition, expected extraction factors and ultimate financial viability before any mining starts. As material is removed from the slimes dams for retreatment, the resources and reserves for that operation are adjusted accordingly. Continual checks on modifying factors and ongoing surveys are conducted to monitor the rate of depletion and the accuracy of factors used for conversion.

Independent review

DRDGOLD’s statements of its mineral resources and mineral reserves were independently reviewed by Coffey Mining for compliance with the SAMREC Code, the National Instrument 43-101 and the US SEC Industry Guide 7. Coffey Mining is an exploration, mining and resource consulting firm, which has been providing services and advice to the international mineral industry and to various financial institutions since 1987.

The review report for the operations was compiled by Dave Whittaker, BSc (Hons) (Geology) (Pr Sci Nat) and Kathleen Body (Pr Sci Nat). Coffey Mining has the appropriate qualifications, experience, competence and independence to be considered independent “competent persons” or “qualified persons” in terms of the definitions provided in the codes and instruments.

Coffey Mining staff members carried out quality control analysis of the data during numerous site visits to the different surface and underground operations. They reviewed the geological models, grade estimation techniques, the conversion from resources to reserves, underground operations and transport systems, and assessed the procedures and parameters used in the preparation of these mineral resources and mineral reserves statements.

Competent person

The information in this Integrated Report relating to mineral resources, mineral reserves or exploration results is based on information compiled by the competent person.

Gary John Viljoen (PLATO) is the competent person responsible for the compilation and reporting of DRDGOLD’s mineral resources and mineral reserves.

This person has extensive (more than five years) relevant experience in the mining industry and in working with the type of deposits mined. He is the designated competent person in terms of the SAMREC Code, and is a registered member of the recognised statutory organisations.

Declaration

The gold price used for declaration is R378 158/kg (US$1 192/oz and R9.8675/US$). For compliance with the SEC, DRDGOLD’s Form 20-F (to be filed with the SEC) will also quote the mineral reserves using the three-year average gold price of R392 955/kg (US$1 549/oz and R7.8904/US$).

All mineral resources declared in this report are inclusive of mineral reserves.

Exploration and project development

Exploration and project development during the year continued to enhance DRDGOLD’s strategy to extend and replace existing production ounces.

ERPM Extensions 1 and 2

DRDGOLD has a prospecting right covering an area of 1 252ha of the adjacent Sallies mine, referred to as ERPM Extension 1. The estimated total resource for ERPM Extension 1 is 36.5Mt at 8.5g/t (9.97Moz). The regional geology of the area indicates that there will be a strike change due to faulting associated with an east-west trending sinistral tear fault. In order to confirm the anticipated change in the geological structure and hence payshoot orientation, it is envisaged that prospecting will take place through development situated 50m in the footwall. Owing to high induced stress experienced at depth, there will be concurrent over-stoping on the reef plane for safety reasons.

In 2007 ERPM’s prospecting right over ERPM Extension 1 was extended eastwards into the Rooikraal/ Withok area, incorporating the southern section of the old Van Dyk mining lease area and a small portion of Sallies. Known as ERPM Extension 2, the additional area is 5 500ha in size and is recognised as one of the largest virtually unexplored areas on the East Rand. The reef lies at a depth of between 1 877m and 2 613m below surface.

The resource for ERPM Extension 2 was estimated in 2007 by independent consultants Camden Geoserve and Minxcon, and reviewed by Coffey Mining. An inferred resource of 28.6Mt at 9.06g/t (8.32Moz) at a stope width of 125cm was declared. The payshoot area equates to 17% of the prospecting right after applying geological losses of 4%.

The evaluation methodology applied was a global Sichel-t estimatator, based on five historical surface boreholes with grades ranging from 107 centimetre grams per tonne (cmgt) to 3 346cmgt. A sixth hole, drilled from underground and reportedly assaying at 2 479cmgt, was excluded from the estimate as it could not be verified.

The ERPM asset has been placed on the market and is for sale.

Mineral resources – 30 June 2013
  Measured Indicated Inferred Total
 
 
Tonnes
Mt
Grade
g/t
Contents
Au Tons
Contents
Moz
Tonnes
Mt
Grade
g/t
Contents
Au Tons
Contents
Moz
Tonnes
Mt
Grade
g/t
Contents
Au Tons
Contents
Moz
Tonnes
Mt
Grade
g/t
Contents
Au Tons
Contents
Moz
ERPM (100%)                                
Underground 5.154 6.92 35.655 1.146 13.568 7.48 101.424 3.261 160.621 6.72 1 080.173 34.728 179.343 6.79 1 217.252 39.136
Total 5.154 6.92 35.655 1.146 13.568 7.48 101.424 3.261 160.621 6.72 1 080.173 34.728 179.343 6.79 1 217.252 39.136
ERGO (100%)                              
Surface 239.899 0.34 80.796 2.598 374.668 0.25 91.811 2.952 841.631 0.21 178.999 5.755 1 456.198 0.24 351.606 11.304
Total 239.899 0.34 80.796 2.598 374.668 0.25 91.811 2.952 841.631 0.21 178.999 5.755 1 456.198 0.24 351.606 11.304
EMO (100%)                              
Underground 5.154 6.92 35.655 1.146 13.568 7.48 101.424 3.261 160.621 6.72 1 080.173 34.728 179.343 6.79 1 217.252 39.136
Surface 239.899 0.34 80.796 2.598 374.668 0.25 91.811 2.952 841.631 0.21 178.999 5.755 1 456.198 0.24 351.606 11.304
Total 245.053 0.48 116.451 3.744 388.236 0.50 193.235 6.213 1002.252 1.26 1 259.172 40.483 1 635.541 0.96 1 568.858 50.440
DRDGOLD                              
Attributable                              
Underground 3.814 6.92 26.385 0.848 10.040 7.48 75.054 2.413 118.860 6.72 799.328 25.699 132.714 6.79 900.767 28.960
Surface 177.525 0.34 59.789 1.922 277.254 0.25 67.940 2.184 622.807 0.21 132.459 4.259 1 077.586 0.24 260.188 8.365
Total 181.339 0.48 86.174 2.770 287.294 0.50 142.994 4.597 741.667 1.26 931.787 29.958 1 210.300 0.96 1 160.955 37.325
Mineral reserves – 30 June 2013
Proved Probable Total
  Delivered to plant Delivered to plant Delivered to plant
  Tonnes
Mt
Grade
g/t
Contents
Au Tons
Contents
Moz
Tonnes
Mt
Grade
g/t
Contents
Au Tons
Contents
Moz
Tonnes
Mt
Grade
g/t
Contents
Au Tons
Contents
Moz
ERGO (100%)                      
Surface 151.154 0.33 49.647 1.596 46.205 0.45 20.795 0.669 197.359 0.36 70.442 2.265
Total 151.154 0.33 49.647 1.596 46.205 0.45 20.795 0.669 197.359 0.36 70.442 2.265
DRDGOLD
Attributable
                     
Surface 111.854 0.33 36.739 1.181 34.192 0.45 15.388 0.495 146.046 0.36 52.127 1.676
Total 111.854 0.33 36.739 1.181 34.192 0.45 15.388 0.495 146.046 0.36 52.127 1.676