Integrated
Annual Report
2018
2018
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The summary of Gold Fields' Mineral Resources and Mineral Reserves in this section should be read in conjunction with the Gold Fields Mineral Resource and Mineral Reserve Supplement (the Supplement), which sets out important and detailed information on the Company's Mineral Resources and Mineral Reserves as at 31 December 2018. The Supplement can be found on our website on www.goldfields.com.
Gold Fields' December 2018 Resource and Reserve position reflects the Company's growth strategy of consistent funding of brownfield exploration, reinvestment in the sustainability and growth of the operations, embedded Business Improvement programmes and advancement of selected growth projects.
Gold Fields continued with its strategy of focusing on brownfields (near-mine) exploration at our Australian and Ghanaian mines to extend the life of our mines. During 2018, our Australian mines again replaced more Reserves than they mined. The emphasis at all mine sites is to strive for Mineral Reserve growth that replaces annual depletion, improves cash-flow and costs per ounce, and maintains momentum on discovery. The sites are also encouraged to convert Resources to Reserves to maintain business plan production profiles and cash-flow projections.
Our strategy also seeks to assess emerging in-country opportunities to leverage off our existing infrastructure and resources and boost the medium to longer-term life of our portfolio. The successful feasibility study at Salares Norte, leading to the conversion of the Mineral Resource to a maiden 4Moz gold equivalent Mineral Reserve, is positive evidence of this strategy.
Key projects supporting the Company's Resource and Reserve development strategy continued during 2018. Apart from the progress at Salares Norte, these projects include the operating model restructuring at South Deep, delivering on key milestones of the Damang Reinvestment plan, significant life extension at Cerro Corona and advancing the Gruyere project construction schedule to a point where full mining of the pit looks set to commence in Q2 2019.
This declaration is based on a Mineral Resource gold price of US$1,400/oz (A$1,850/oz; R600,000/kg) and a Mineral Reserve price of US$1,200/oz (A$1,600/oz; R525,000/kg). The gold price of US$1,200/oz used for the Mineral Reserve declaration is within the guidelines of the United States (US) Securities and Exchange Commission (SEC). The copper price used for the Mineral Resource estimation is US$3.20/lb and for the Mineral Reserve estimation US$2.50/lb, increasing to US$2.80/lb from 2020 onward, with the respective prices used for silver being $20/oz and $17.50/oz. The following exchange rates were used for Mineral Reserve planning purposes: R/US$13.6, R/A$10.2, and A$/US$0.75.
For reporting Mineral Resources and Mineral Reserves, Gold Fields' over-arching principle is to ensure transparency, materiality and competency in reporting, compliance with public regulatory codes and internal standards, and to inform all stakeholders of relevant material issues regarding the status of the Group's fundamental asset base.
The Group's December 2018 Mineral Resource and Mineral Reserve estimate is in accordance with the requirements of the South African Code for the Reporting of Exploration Results, Mineral Resources and Mineral Reserves (the SAMREC Code, 2016), the South African Code for the Reporting of Mineral Asset Valuation (2016 SAMVAL Code) and Industry Guide 7 for reporting on the US SEC. The SAMREC Code covers public reporting and information that is prepared for investors or potential investors and their advisers, as well as other interested parties.
Reporting is also in accordance with section 12 of the Johannesburg Stock Exchange Limited (JSE) Listings Requirements and takes cognisance of other relevant international codes, where geographically applicable. The definitions contained in the SAMREC Code are either identical to, or not materially different from, equivalent international codes.
The December 2018 declaration aims to report on information that is rated as important for disclosure on Mineral Resources and Mineral Reserves and it reflects a level of detail required for completeness, transparency and materiality in reporting. Gold Fields' Mineral Resources and Mineral Reserves are reviewed on an ongoing basis by an internal Competent Person team administered by Corporate Technical Services and cyclically, at least every three years, by external and independent experts, details of which are published in the Supplement. The Competent Persons designated in terms of SAMREC, who assume responsibility for the reporting of Mineral Resources and Mineral Reserves, are the respective operation-based geology, technical and relevant project managers. The relevant Competent Persons are listed in the Supplement to this Integrated Annual Report.
At 31 December 2018, Gold Fields' mines and projects had total attributable gold and copper Mineral Resources of 96.6Moz (December 2017: 103.8Moz) and 4,816Mlbs (December 2017: 4,881Mlbs), respectively. Attributable gold and copper Mineral Reserves are 48.1Moz (December 2017: 49Moz) and 691Mlbs (December 2017: 764Mlbs) respectively, net of mined depletion. Total gold-equivalent Mineral Resources are 108.22Moz (December 2017: 115.60Moz) and Mineral Reserves 50.26Moz (2017: 50.80Moz). South Deep currently accounts for 47% of gold-equivalent Mineral Resources and 59% of Mineral Reserves.
The charts below depict the Group's comparative 2018 and 2017 managed gold Mineral Resource and Mineral Reserve ounces split by region and growth projects. Detailed year-on-year reconciliations are set out in the Supplement.
| Managed gold Mineral Resources1, 2 | Managed gold Mineral Reserves1 | |
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| 1 Salares Norte and Gruyere are included in the Americas and Australia regions respectively 2 The Growth Project Resource now reflects the FSE project only |
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| Managed Mineral Resources | Attributable ounces | |||||||||||||
| 31 Dec 2018 | 31 Dec 2017 | 31 Dec 2018 |
31 Dec 2017 |
|||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Gold only | Tonnes (Mt) |
Grade (g/t) |
Au (Moz) |
Tonnes (Mt) |
Grade (g/t) |
Au (Moz) |
Gold (Moz) | |||||||
| Total regions2 | 1,002.1 | 2.96 | 95.5 | 1,010.8 | 3.18 | 103.3 | 88.7 | 95.8 | ||||||
| Total projects3 | 891.7 | 0.69 | 19.8 | 891.7 | 0.69 | 19.8 | 7.9 | 7.9 | ||||||
| Total Au only | 1,893.8 | 1.89 | 115.3 | 1,902.5 | 2.01 | 123.1 | 96.6 | 103.8 | ||||||
| Cu and Ag as Au equiv. | Individual metals detailed in table below | |||||||||||||
| Cerro Corona Cu as Au Equiv.5 | 1.9 | 2.1 | 1.9 | 2.1 | ||||||||||
| FSE Cu as Au Equiv.6 | 22.7 | 22.7 | 9.1 | 9.1 | ||||||||||
| Salares Norte Ag as Au Equiv.7 | 0.6 | 0.7 | 0.6 | 0.7 | ||||||||||
| Grand total as Au equivalents | 140.5 | 148.6 | 108.2 | 115.6 | ||||||||||
| Managed Mineral Resources | Attributable ounces | |||||||||||||
| 31 Dec 2018 | 31 Dec 2017 | 31 Dec 2018 |
31 Dec 2017 |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Gold | Tonnes (Mt) |
Grade (g/t) |
Au (koz) |
Tonnes (Mt) |
Grade (g/t) |
Au (koz) |
Resource (koz) | |||||||
| Australia region | ||||||||||||||
| Agnew | 12.3 | 5.16 | 2,049 | 11.5 | 5.25 | 1,946 | 2,049 | 1,946 | ||||||
| Granny Smith | 46.2 | 5.27 | 7,837 | 38.6 | 5.70 | 7,075 | 7,837 | 7,075 | ||||||
| St Ives | 33.2 | 3.68 | 3,928 | 34.4 | 3.47 | 3,847 | 3,928 | 3,847 | ||||||
| Gruyere | 77.7 | 1.32 | 3,305 | 75.4 | 1.29 | 3,134 | 3,305 | 3,134 | ||||||
| Total Australia region | 169.5 | 3.14 | 17,120 | 160.0 | 3.11 | 16,002 | 17,120 | 16,002 | ||||||
| South African region | ||||||||||||||
| South Deep2 | 328.0 | 5.32 | 56,152 | 381.6 | 5.41 | 66,318 | 50,955 | 60,350 | ||||||
| Total South Africa region | 328.0 | 5.32 | 56,152 | 381.6 | 5.41 | 66,318 | 50,955 | 60,350 | ||||||
| Americas region | ||||||||||||||
| Cerro Corona | 107.7 | 0.65 | 2,263 | 115.0 | 0.69 | 2,542 | 2,252 | 2,530 | ||||||
| Salares Norte | 25.6 | 4.76 | 3,910 | 23.3 | 4.89 | 3,663 | 3,910 | 3,663 | ||||||
| Total Americas region | 133.2 | 1.44 | 6,173 | 138.3 | 1.40 | 6,205 | 6,162 | 6,193 | ||||||
| West Africa region | ||||||||||||||
| Damang | 85.1 | 2.21 | 6,058 | 86.2 | 2.21 | 6,119 | 5,452 | 5,507 | ||||||
| Tarkwa – open pits | 213.2 | 1.30 | 8,891 | 172.5 | 1.37 | 7,583 | 8,002 | 6,825 | ||||||
| Tarkwa – surface stocks | 73.1 | 0.46 | 1,091 | 72.2 | 0.46 | 1,074 | 982 | 967 | ||||||
| Tarkwa – total | 286.3 | 1.08 | 9,983 | 244.8 | 1.10 | 8,658 | 8,984 | 7,792 | ||||||
| Total West Africa region | 371.4 | 1.34 | 16,040 | 331.0 | 1.39 | 14,776 | 14,436 | 13,299 | ||||||
| Gold only | ||||||||||||||
| GFL Operations – Total Gold | 1,002.1 | 2.96 | 95,485 | 1,010.8 | 3.18 | 103,301 | 88,674 | 95,843 | ||||||
| Managed Mineral Resources | Attributable ounces | |||||||||||||
| Americas region Copper | Tonnes (Mt) |
Grade (% Cu) |
Copper (Mlbs) |
Tonnes (Mt) |
Grade (% Cu) |
Copper (koz) |
Attributable Copper (Mlbs) |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cerro Corona Cu only | 102.4 | 0.37 | 848 | 107.9 | 0.39 | 917 | 844 | 913 | ||||||
| Managed Mineral Resources | Attributable ounces | |||||||||||||
| Americas region Silver | Tonnes (Mt) |
Grade (% Cu) |
Ag (Mlbs) |
Tonnes (Mt) |
Grade (% Cu) |
Ag (koz) |
Attributable Silver (koz) |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Salares Norte Ag only | 25.6 | 53.13 | 43,664 | 23.3 | 66.03 | 49,458 | 43,664 | 49,458 | ||||||
* Including Gruyere and Salares Norte
| Managed Mineral Reserves | Attributable ounces | |||||||||||||
| 31 Dec 2018 | 31 Dec 2017 | 31 Dec 2018 |
31 Dec 2017 |
|||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Gold only | Tonnes (Mt) |
Grade (g/t) |
Au (Moz) |
Tonnes (Mt) |
Grade (g/t) |
Au (Moz) |
Gold (Moz) | |||||||
| Total regions2, 3 | 589.1 | 2.74 | 51.9 | 613.1 | 2.70 | 53.1 | 48.1 | 49.0 | ||||||
| Cu and Ag as Au equiv. | Individual metals detailed in table below | |||||||||||||
| Cerro Corona Cu as Au Equiv.8 | 1.6 | 1.8 | 1.6 | 1.8 | ||||||||||
| Salares Norte Ag as Au Equiv.9 | 0.6 | — | 0.6 | — | ||||||||||
| Grand total as Au equivalents | 54.0 | 54.9 | 50.3 | 50.8 | ||||||||||
| Managed Mineral Reserves | Attributable ounces | |||||||||||||
| 31 Dec 2018 | 31 Dec 2017 | 31 Dec 2018 |
31 Dec 2017 |
|||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Gold | Tonnes (Mt) |
Grade (g/t) |
Gold (koz) |
Tonnes (Mt) |
Grade (g/t) |
Gold (koz) |
Reserves (koz) | |||||||
| Australia region | ||||||||||||||
| Agnew | 3.7 | 4.72 | 560 | 3.0 | 5.54 | 541 | 560 | 541 | ||||||
| Granny Smith | 12.6 | 5.54 | 2,246 | 12.4 | 5.51 | 2,203 | 2,246 | 2,203 | ||||||
| St Ives | 19.1 | 2.84 | 1,741 | 19.4 | 2.51 | 1,568 | 1,741 | 1,568 | ||||||
| Gruyere | 47.1 | 1.25 | 1,894 | 48.7 | 1.20 | 1,871 | 1,894 | 1,871 | ||||||
| Total Australia region | 82.5 | 2.43 | 6,441 | 83.6 | 2.30 | 6,183 | 6,441 | 6,183 | ||||||
| South African region | ||||||||||||||
| South Deep4 | 182.3 | 5.60 | 32,808 | 216.8 | 5.36 | 37,388 | 29,772 | 34,023 | ||||||
| Total South Africa region | 182.3 | 5.60 | 32,808 | 216.8 | 5.36 | 37,388 | 29,772 | 34,023 | ||||||
| Americas region | ||||||||||||||
| Cerro Corona | 79.9 | 0.68 | 1,737 | 86.2 | 0.70 | 1,937 | 1,729 | 1,928 | ||||||
| Salares Norte | 21.1 | 5.13 | 3,476 | 3,476 | — | |||||||||
| Total Americas region | 101.0 | 1.61 | 5,213 | 86.2 | 0.70 | 1,937 | 5,205 | 1,928 | ||||||
| West Africa region | ||||||||||||||
| Damang | 28.9 | 1.74 | 1,616 | 31.9 | 1.68 | 1,728 | 1,454 | 1,555 | ||||||
| Tarkwa – open pits | 121.4 | 1.20 | 4,687 | 122.5 | 1.23 | 4,831 | 4,218 | 4,348 | ||||||
| Tarkwa – surface stocks | 73.1 | 0.46 | 1,091 | 72.2 | 0.46 | 1,074 | 982 | 967 | ||||||
| Tarkwa – Total | 194.5 | 0.92 | 5,778 | 194.7 | 0.94 | 5,906 | 5,200 | 5,315 | ||||||
| Total West Africa region | 223.4 | 1.03 | 7,394 | 226.6 | 1.05 | 7,634 | 6,654 | 6,871 | ||||||
| Gold only | — | — | ||||||||||||
| Total Gold | 589.1 | 2.74 | 51,856 | 613.1 | 2.70 | 53,143 | 48,072 | 49,005 | ||||||
| Managed Mineral Resources | Attributable ounces | |||||||||||||
| (PERU) – Cerro Corona Copper |
Tonnes (Mt) |
Grade (% Cu) |
Copper (Mlbs) |
Tonnes (Mt) |
Grade (% Cu) |
Copper (koz) |
Attributable Copper (Mlbs) |
|||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Copper (Cu) only | 79.9 | 0.39 | 695 | 86.2 | 0.40 | 767 | 691 | 764 | ||||||
| Managed Mineral Resources | Attributable ounces | |||||||||||||
| (CHILE) – Salares Norte Silver |
Tonnes (Mt) |
Grade (g/t Ag) |
Ag (koz) |
Tonnes (Mt) |
Grade (g/t Ag) |
Ag (koz) |
Attributable Silver (koz) |
|||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Silver (Ag) only | 21.1 | 57.94 | 39,263 | — | — | — | 39,263 | — | ||||||
| 1 | Managed unless otherwise stated; Gruyere only reports the 50% share attributable to Gold Fields; Measured and Indicated Mineral Resources are reported inclusive of those Mineral Resources modified to produce Mineral Reserves |
| 2 | Gruyere and Salares Norte are included in the Australia and Americas regions, respectively |
| 3 | Projects - FSE Inferred Resource only |
| 4 | Reserve grade is inclusive of in section development tonnes, which cannot be separated from the ore flow, however, capital waste is excluded as there is a potential to separate it in the future |
| 5 | Metal prices used for equiv oz: US$1,400/oz Au and US$3.2/lb Cu. The metallurgical recovery rate (Au=69% and Cu=87%) and selling cost, have not been applied to the conversion. Calculation: CuMlbs*Cu Price (848*3.2)/Au price (1,400) = 1.9 Au equivalent Moz |
| 6 | Metal prices used for equiv oz: US$1,400/oz Au and US$3.2/lb Cu. The selling cost, including refining and royalties, plus metallurgical recovery rate (Au=82% and Cu=93%) and selling cost have not been applied to the conversion. Calculation: CuMlbs*Cu Price (9,921*3.2)/Au price (1,400) = 22.7 Au equivalent Moz |
| 7 | Metal prices used for equiv oz: US$1,400/oz Au and US$20/oz Ag. Equivalency is based on the price ratio only so the metallurgical recoveries (92% Au, 68% Ag) and selling costs (US$16.76/oz Au, US$1.41/oz Ag), including refining and royalties (1%), have not been included. (43.7*20/1400 = 0.6Moz Au equivalent) |
| 8 | Metal prices used for equiv oz: US$1,200/oz Au and US$2.8/lb Cu. The selling cost, including refining and royalties, plus metallurgical recovery rate (Au=69% and Cu=87%), has not been applied to the conversion. Calculation: CuMlbs*Cu Price (695*2.8)/Au price (1,200) = 1.6 Au equivalent Moz |
| 9 | Metal prices used for equiv oz: US$1,200/oz Au and US$17.5/oz Ag. The selling cost, including refining and royalties, plus metallurgical recovery rate (Au=93% and Cu=68%), has not been applied to the conversion. Calculation: Agkoz*Ag Price (39.3*17.5)/Au price/oz (1,200) = 0.6 Au equivalent Moz |