Reserves/Resource Statement

Ore Reserves and Mineral Resources

The Ore Reserves and Mineral Resources estimates for Tropicana are updated on an annual basis. AngloGold Ashanti and Independence Group provide full details of these estimates, including the applicable JORC statements, on their websites: www.anglogoldashanti.com and www.igo.com.au.

Tropicana Ore Reserves (100% Project) as at 31 December 2016
Area

Reserves
Category

 

Dec 15 Dec 16 Change
Mt g/t Moz Mt g/t Moz Mt g/t Moz
Open Pit (inlc. in Stockpiles Proved 18.8 1.67 1.01 15.7  1.48 0.75 -3.1 -0.19 -0.26
Provable 25.3 1.98 1.61 44.4 2.14 3.05 19.1 0.16 1.44
Total 44.0 1.85 2.62 60.1 1.97 3.80 16.1 0.12 1.18
Underground Proved 0.0 0.00 0.00 0.0 0.00 0.00 0.0 0.00 0.00
Provable 0.0 0.00 0.00 0.0 0.00 0.00 0.0 0.00 0.00
Total 0.0 0.00 0.00 0.0 0.00 0.00 0.00 0.00 0.00
Total Proved 18.8 1.67 1.01 15.7 1.48 0.75 -3.1 -0.19 -0.26
Provable 25.3 1.98 1.61 44.4 2.14 3.05 19.1 0.16 1.44
Total 44.0 1.85 2.62 60.1 1.97 3.80 16.1 0.12 1.18

 

Tropicana Mineral Resources (100% Project) as at 31 December 2016
Area 

Resources
Classification

Dec 15 Dec 16 Change
Mt g/t Moz Mt g/t Moz Mt g/t Moz
Open Pit (incl. in Stockpiles) Measured 27.9 1.35 1.21 26.1 1.13 0.94 -1.8 -0.22 -0.27
Indicated 73.1 1.69 3.97 81.1 1.61 4.19 8.0 -0.08 0.22
Inferred 1.9 2.22 0.13 22.3 1.32 0.94 20.4 -0.91 0.81
Total 102.9 1.61 5.32 129.5 1.46 6.08 26.6 -0.15 0.77
Underground Measured 0.0 0.00 0.00 0.0 0.00 0.00 0.0 0.00 0.00
Indicated 3.3 3.61 0.38 6.8 3.38 0.73 3.5 -0.23 0.35
Inferred 5.8 3.13 0.59 11.9 3.15 1.20 6.0 0.02 0.62
Total 9.1 3.31 0.97 18.6 3.23 1.94 9.5 -0.07 0.97
Total Measured 27.9 1.35 1.21 26.1 1.13 0.94 -1.8 -0.22 -0.27
Indicated 76.4 1.77 4.35 87.9 1.74 4.93 11.4 -0.03 0.58
Inferred 7.7 2.91 0.72 34.2 1.95 2.15 26.5 -0.96 1.42
Total 112.1 1.74 6.28 148.1 1.68 8.02 36.1 -0.06 1.73


Notes:

The Open Pit Mineral Resources have been estimated using the geostatistical technique of Localised Uniform Conditioning (LUC) using average drill hole intercepts. Isatis software was used for the estimation. The Open Pit Mineral Resources have been reported above a marginal (break-even) cut-off grade of 0.3 g/t for oxide and transitional material and 0.4 g/t for fresh material, within a US$1,400 optimisation at an A$/US$exchange rate of 0.82 (A$1,704).
The Havana Deeps Underground Mineral Resource was not re-estimated during 2015. The Mineral Resource was estimated in 2012 using the geostatistical technique of Ordinary Kriging using average drill-hole intercepts. Isatis sofware was used for the estimation. The Havana Deeps Underground Mineral Resource is reported externally to the A$1,704 optimisation, at a cut-off grade of 2.0 g/t.
The 2015 Tropicana Gold Project Mineral Resource stands at 6.28Moz, a decrease of 0.9Moz on the previous year. Mineral Resources remain open down-dip for all zones, and to the south of the HavanaZone.
The Ore Reserve has been estimated above the economic break-even cut-off grades presented in the table below. The cut-off grade are calculated at the nominated gold price of US$1,100/oz and an exchange rate of 0.77 US$/A$ which is equivalent to A$1,436/oz, as per the corporate guidelines - Excom economic assumptions proposal V4 Ref[9].
Due to the relative small volumes of some of the material types, forcut-off grade calculation purposes, 2 groups were created, Oxide and Fresh. This also facilitated a practical and ease of operation consideration.


Regolith Gold Cut-off (g/t)
Transported
Upper Saprolite
Lower Saprolite
SapRock
Fresh Rock
0.5


0.7

 

JORC Code Statements - Tropicana Gold Project Mineral Resource and Ore Reserve estimates

The information in this report that relates to Mineral Resources estimates was based on information compiled by Mr Mark Kent, a full-time employee of AngloGold Ashanti Australia Limited, who is a member of the Australasian Institute of Mining and Metallurgy. Mr Kent has sufficient experience relevant to the type and style of mineral deposits under consideration, and to the activity which has been undertaken, to qualify as a Competent Person as defined in the 2012 edition of the JORC Code. Mr Kent consented to the release of the Mineral Resource estimated, based on the information in the form and context in which it appears in this report.
The information that relates to Ore Reserves estimated was based on information compiled by Jason Vos, a full-time employee of AngloGold Ashanti Australia Limited, who is a member of the Australasian Institute of Mining and Metallurgy. Mr Voshas sufficient experience relevant to the type and style of mineral deposit under consideration, and to the activity which has been undertaken, to qualify as a Competent Person as defined in the 2012 edition of the JORC Code. Mr Vos has consented to the release of the Ore Reserve estimate, based on the information, in the form and context in which it appears in this report.

 

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