Auryx Gold Corp.

Auryx Gold Corp.

September 12, 2011 06:00 ET

Auryx Receives a Positive PEA for Otjikoto Pre-Tax NPV of USD301 Million and IRR of 42%

TORONTO, ONTARIO--(Marketwire - Sept. 12, 2011) - Auryx Gold Corp. ("Auryx" or the "Company") (TSX:AYX)(NSX:AYX) is pleased to announce the results of the Preliminary Economic Assessment ("PEA") on the Otjikoto gold project (the "Project") in Namibia.

Highlights Include:

  • Pre-tax NPV of USD301 million at a 5% discount rate and an IRR of 42% at a gold price of USD1,300/oz and an exchange rate of Namibian Dollar ("NAD") 7.50 to the USD;
  • Initial capital costs of USD130 million and ongoing capital of USD15 million (assuming contractor mining);
  • Average annual production of 109,000 ounces of gold over a 10 year life of mine ("LoM");
  • Average LoM cash operating costs using contractor mining of USD691/oz before operating contingency (USD725/oz including contingency);
  • Average LoM run of mine ("RoM") head grade of 1.71g/t (1.52g/t including processing of low grade ore);

The PEA has been prepared by SRK Consulting (South Africa) (Pty) Ltd ("SRK") with input of a number of independent consultants including Scorpion Mineral Processing (Pty) Ltd ("SMP"), VBKom Consulting Engineers (Pty) Ltd ("VBKom"), and Geo Tail. The PEA is preliminary in nature and includes inferred mineral resources that are considered too speculative geologically to have the economic considerations applied to them that would enable them to be categorized as mineral reserves, and there is no certainty that the PEA will be realized.

Using a gold price assumption of USD1,300/oz and an exchange rate of NAD7.50/USD, the Project's pre-tax NPV is USD301 million and the pre-tax IRR is 42%. The Company views the price assumptions used as conservative and notes that the base case uses a gold price that is 29% below spot and a currency that is 12.5% above spot. At a gold price of USD1,500/oz and an exchange rate of NAD8.0/USD, Otjikoto's pre-tax NPV and IRR are USD474 million and 57% respectively.

The Project's initial CAPEX using contractor mining is estimated at USD130 million and includes a contingency allowance of 19%. Sustaining Capital and Owners' Costs are USD15 million and USD3.4 million respectively. The LoM cash operating costs are estimated at USD725/oz (including contingency) which reflects the Project's modelled strip rate of 7.3:1.

Tim Searcy, CEO of Auryx Gold stated: "We are very pleased with the results of the PEA. It demonstrates that the Otjikoto gold deposit is a very robust project, which benefits significantly from the local infrastructure. Road, rail, and water are accessed at site and grid power is available very close by, all of which positively impact the initial CAPEX estimate. Furthermore, a number of additional opportunities exist to improve on these results including new zones that have been discovered but not yet included into the mine model and the potential for saleable by-product concentrates of sulfides and iron-oxides."

Mineral Resources

The mineral resource estimate (NI 43-101 compliant) presented in the PEA were first released on 3 February 2011. The resources have been reported according to the guidelines of the CIM Standing Committee.

Table 1: Otjikoto Mineral Resources reported above a 0.4g/t cut-off (effective as of 31 December 2010)*

Indicated Mineral Resources Inferred Mineral Resources
Au Grade

Au Grade

0.4 - 0.8 9.34 0.60 0.18 7.21 0.59 0.14
> 0.8 15.78 1.94 0.98 8.37 1.94 0.52
Total 25.12 1.44 1.16 15.58 1.31 0.66
*Mineral resources that are not mineral reserves do not have demonstrated economic viability.


A pit optimisation was carried out using the Whittle Four-X® software. For a given block model, cost, recovery and slope data, Whittle Four-X® software calculates a series of incremental pit shells within which each shell is an optimum for a slightly higher commodity price factor. After selecting the optimal pit shell, a pit design which incorporates access ramps, bench configurations and mining constraints was developed in Surpac®. Lower revenue factor shells from the pit optimisation exercise were selected to serve as push backs and assist in scheduling the operation. The material inside the pit design was then scheduled in XPAC® software according to feasible tonnage and grade targets. A low grade stockpile was introduced to allow the selective processing of high grade ore. The labour and mobile equipment requirements are based on the mining schedule developed in XPAC®. The mining capital and operating expenditure estimates were derived from first principles.

Processing Facility

Metallurgical testwork conducted over the last 10 years has been used to define a processing route. The testwork was conducted by various accredited laboratories, including Mintek in Johannesburg, and indicated average overall metallurgical recoveries of 88% for the oxide material and 91% for the fresh sulfide material through a bulk flotation and leach process. The testwork highlighted a high level of gravity recoverable gold in the ore body.

The plant consists of a conventional flotation and carbon-in-leach ("CIL") circuit made up of the following unit processes: crushing, milling, gravity gold recovery, flotation, CIL, electrowinning and smelting. Crushing will be achieved in two stages with a primary jaw crusher and a closed circuit secondary cone crusher. The crushed ore is fed into a single stage milling and gravity gold recovery circuit before feeding the flotation circuit. The flotation circuit consists of rougher scavenger, and cleaner cells. The flotation concentrate is thickened and then pumped to the regrind milling circuit. The liberated ore is then fed to a CIL circuit where the gold is recovered by activated carbon. The gold is stripped from the activated carbon in an Anglo American Research Laboratory ("AARL") elution circuit that generates pregnant solution. The pregnant solution from the gravity circuit and the CIL circuit is then plated in an electrowinning step, and smelted on site to produce doré bullion bars.

High and low sulfide waste streams will be produced by the plant from the CIL and flotation circuits respectively. Both streams will be pumped as slurries to the tailings disposal facility ("TDF"). Paste thickening (on the low sulphide stream) will be pumped to the TDF as a paste and filtration (on the high sulfide stream) will produce filter cake that will be deposited on the lined TDF with a conveyor system. This approach maximises the water recovery.

The proposed mine processing plant production schedule is shown graphically in Figure 1 below.

Figure 1:

Tailings Disposal Facility

The slurry pumped from the process plant will pass through the paste thickener or filtration systems located at the TDF before being fed into the basins of the storage facilities. Paste will be pumped to the unlined TDF located in a natural depression with a calcrete surface layer of between 15 and 30 m thickness. Water recovered from the low sulphide TDF will be pumped to a return water dam. Dry deposition of the filter cake using a conveyor system will be used for the lined high sulfide TDF. Water recovered from this facility will drain to a return water dam.

The benefits of this approach on the design, due to the lower water content in the tailings stream, are as follows: a) more efficient volumetric storage; b) a reduced risk of groundwater contamination; c) less make-up water demand; d) a more stable structure; and e) accelerated rehabilitation potential.


The total installed power requirement for the facility is 11.5 MW and this will be supplied from the national grid. An application has been submitted to the relevant authorities for the supply of this power to the facility. During a technical review with the authorities, a tap off point was identified on the 220 kV main line, which runs on a line 16 km west of the plant, and feeds the northern Namibia region. This tap off point was recognized as the preferred supply route.

Capital Costs

The estimated capital requirements for the project are shown in Table 2. Variable contingencies have been applied by project activity and give an average contingency allowance of 19% for the project capital. The mine equipment capital estimate is for a contractor operated mine. If Auryx elects to conduct the mining itself, the project and sustaining capital for the Otjikoto Project increases to USD161 million and USD52 million respectively.

Table 2: Summary of the estimated Capital Costs (Contractor Mining)

Item Project Capital
Sustaining Capital
Construction Phase capital 0.85 0
Processing 55.70 0
Plant and Administration Infrastructure 2.36 0
Mine and other Infrastructure 6.55 0
Tailings Disposal Facility 21.20 4.02
Power Supply 4.55 0
Laboratory 0.87 0
Miscellaneous Infrastructure 1.17 0
Owner's Cost 3.44 0
Mining Fleet 2.92 1.11
EPCM 10.22 0.52
Contingencies 19.91 0.67
Sustaining Capital 0 8.69
Total 129.74 15.00

Operating Costs

The total estimated operating costs for the LoM with contractor mining, as incorporated into the PEA, are set out in the Table 3. The average unit mining cost over the LoM is USD2.05/t of total material (high grade and low grade ore plus waste) mined.

Table 3: Summary of the estimated Operating Costs for the LoM (Contractor Mining)

LoM Operating Cost
Description Total
Unit Cost
(USD/t processed)
Processing 288.81 11.01
Tailings Disposal 9.31 0.35
Mining 447.05 17.05
Admin 65.57 2.50
Total Cash Operating Cost (before contingency) 808.51 30.83
Environmental & Social
Closure Fund Contributions 13.68 0.52
Retrenchment/Downsizing 2.73 0.10
Monitoring 1.20 0.05
Social community support 1.80 0.07
Contingencies 41.40 1.58
Royalties 45.64 1.74
Total Working Costs 914.96 34.89
Unit Cash Operating costs (USD/oz recovered) (USD/t processed)
Mining 381.97 17.05
Processing & Tailings 254.72 11.37
Admin 54.12 2.42
Cash Operating Cost 690.81 30.83
Environmental & Social 16.58 0.74
Contingency 35.37 1.58
Royalty 39.00 1.74
Total Working Cost 781.77 34.89

Financial Analysis

The economics of the project have been evaluated at a gold price of USD1,300/oz and an exchange rate of NAD7.5/USD based on a 24-month historic average. The effective date for the PEA is deemed to be 1 September 2011. The PEA demonstrates the potential for significant positive economic returns from developing the Otjikoto Gold Project. The variation in NPV with discount factors is given in Table 4. No formal tax planning was undertaken to optimize the post-tax scenario.

Table 4: Variation of NPV with discount factor (Contractor Mining)

Discount Rate Pre-tax Post-tax
0% 458 286
4% 327 201
5% 301 184
6% 278 169
7% 256 155
8% 236 141
9% 217 129
10% 200 118
12% 170 98

A summary of key economic results on a pre- and post-tax basis for contractor and owner operated mining are compared below in Tables 5 and 6.

Table 5: Key economic results (Contractor Mining)

Summary Units Pre-Tax Post-Tax
NPV @ 5% (USDm) 301 184
IRR 42% 33%
LoM Capital (USDm) 145
Project Capital (USDm) 130
Peak Funding (USDm) 127
Payback years 4.9
Average Au recovered/year (koz) 109
Total Au recovered LoM (koz) 1 170
Unit Cash Operating Cost (Average LoM) (USD/t ore mined) 30.83
(USD/oz) 690.81

Table 6: Key economic results (Owner Operated Mining)

Summary Units Pre-Tax Post-Tax
NPV @ 5% (USDm) 303 184
IRR 36% 29%
LoM Capital 214
Project Capital (USDm) 161
Peak Funding (USDm) 139
Payback years 4.4
Average Au recovered/year (koz) 109
Total Au recovered LoM (koz) 1 170
Unit Cash Operating Cost (Average LoM) (USD/t ore mined) 27.87
(USD/oz) 624.43

The revenue, operating cost, capital cost and gold price NPV sensitivities are presented in Table 7 below.

Table 7: NPV Sensitivity (Contractor Mining)

Sensitivity (NPV @ 5%) Units -20% -15% -10% -5% 0% 5% 10% 15% 20%
Revenue (USDm) 86 140 194 248 301 355 409 463 517
Operating cost (USDm) 424 393 363 332 301 271 240 210 179
Capital cost (USDm) 328 321 315 308 301 295 288 282 275
Revenue (USDm) 48 82 116 150 184 218 252 286 320
Operating cost (USDm) 261 242 223 204 184 165 146 127 107
Capital cost (USDm) 202 198 193 189 184 180 175 171 167
Au Price Sensitivity -15% -12% -8% -4% 0% 4% 8% 12% 15%
Actual Au Price 1 100 1 150 1 200 1 250 1 300 1 350 1 400 1 450 1 500
NPV @ 5% real discount
Pre-tax (USDm) 141 181 221 261 301 342 382 422 462
Post-tax (USDm) 83 108 134 159 184 210 235 260 285

Within the accuracy of the PEA, it is not possible to confirm whether contractor or owner operated mining is the more beneficial route to follow. This decision will be governed by the Company's cost of capital.

Environmental and Social Aspects

All baseline studies have been completed and no fatal flaws have been identified to date. As planned, the primary source of water supply for the mine will be from production boreholes located in the marble aquifers found on the property. Current estimates indicate that four production boreholes will be capable of supplying the bulk water required by the facility, based on yields from adjacent well fields.

Closure costs in the PEA are estimated at USD13.6 million based on preliminary estimates and compared with other operations in Namibia. Currently the project life is estimated at 12 years, with closure occurring 2 years after final mining once the low grade stockpile has been processed.

Project Opportunities

Auryx is actively pursuing a number of alternatives for enhancing and increasing the economics and financial returns relating to the Otjikoto project. These include delineating additional resources within and outside of the modelled pit and evaluating the potential for saleable by-products, such as sulfide and iron-oxide concentrates.

Development Timelines

The Company intends to deliver an updated resource estimate in Q1 2012 and then use that resource for the basis of a FS. The previous guidance on timing of a FS was Q2 2013. The Company believes it can materially advance the delivery and will advise the market on this issue before the end of the 2011.

Qualified Persons

The PEA was prepared by leading independent industry consultants and Qualified Persons ("QPs") under the National Instrument 43-101.

The QP who assumes overall responsibility for the PEA is Mr Andrew McDonald, a Principal Engineer with SRK holding a MSc degree in Geophysics (cum laude) from the University of the Witwatersrand and a MBL from UNISA. He is a registered Chartered Engineer (Reg. No. 334897) through the Institution of Materials, Minerals and Mining in London and is a Fellow of the Southern African Institute of Mining and Metallurgy. He has 37 years of diverse experience in a range of management, technical and financial activities in mining and light industrial industries, the past 16 of which have been involved in the fields of feasibility studies, due-diligence audits, financial evaluation and regulatory reporting for mining-related projects throughout Africa and other international locations. He has undertaken numerous mineral asset valuations since 1995. Mr McDonald has reviewed and approved the content of this press release.

The QP who assumes the responsibility for reporting of the Mineral Resources is Mr Mark Wanless. Mark is an associate Partner, and Principal Geologist with SRK, and is registered as a Professional Natural Scientist with the South African Council for Natural Scientific Professionals Reg: 400178/05 and is also an associate member of the South African Institute for Mining and Metallurgy. Mark has over 15 years of experience in Southern Africa and internationally. His expertise is in due diligence studies, and Mineral Resource estimation. Mark has experience in a range of commodities including Gold, PGEs, base metals, Iron and Manganese, and Mineral sands. Mr Wanless has reviewed and approved the content of this press release.

The QP who assumes the responsibility for the Mining Section of the PEA is Mr Hermanus J Kriel (Pr. Eng.), the Chief Executive Officer of VBKom Consulting Engineers holding a B.Eng. (Mining) from the University of Pretoria and a MBL from UNISA in South Africa. He is a registered Professional Engineer (Reg. No. 20080140) through the Engineering Council of South Africa. He has 16 years of practical and consulting experience on surface and underground mining projects throughout the African continent over the whole commodity spectrum. Mr Kriel has reviewed and approved the content of this press release.

The QP who assumes the responsibility for the Process Plant and the Infrastructure related to the PEA is Mr Matthys J Wessels (Pr. Eng.), a Project Engineer with Scorpion Mineral Processing holding a B.Eng. (Mechanical) from the North-West University in South Africa. He is a registered Professional Engineer (Reg. No. 20050108) through the Engineering Council of South Africa. He has 12 years of diverse experience in a range of technical activities in mining and heavy engineering industries throughout Africa and other international locations. His Engineering experience varies from heavy steel industry to port facilities and mineral processing. Mr Wessels has reviewed and approved the content of this press release.

The QP who assumes responsibility for the PEA for the Tailings Storage Facilities is Mr Guillaume Louw de Swardt, a Director with Geo Tail holding an MSc degree in Civil Engineering from the University of the Witwatersrand. He is a registered Professional Engineer (Reg. No. 950429) through the Engineering Council of South Africa. He has 20 years of diverse experience in geotechnical and tailings engineering. He has been involved in numerous major mining projects on the African continent and his experience in tailings management encompasses the full range of disposal options for different types of tailings. Mr de Swardt has reviewed and approved the content of this press release.

About Auryx Gold Corp.

Auryx Gold Corp. (TSX:AYX)(NSX:AYX) is a Canadian, growth-focused resource company engaged in the acquisition and exploration of gold projects in Namibia. The Company is currently advancing the Otjikoto gold project, located 300km north of Namibia's capital city, Windhoek. By virtue of its location, the project benefits significantly from Namibia's well established infrastructure with paved highways, a railway, power grids, and water grid all close by. Located in the western part of southern Africa, Namibia is lauded as one of the continent's most politically and socially stable jurisdictions.

On behalf of the Board of Directors,

Tim Searcy, P.Geo., Chief Executive Officer

Cautionary Notes

Cautionary Note Concerning Forward Looking Statements

Certain information set forth in this press release contains "forward-looking information" under applicable securities laws. Except for statements of historical fact, certain information contained herein constitutes forward-looking information which include management's assessment of Auryx's future plans and operations and are based on Auryx's current internal expectations, estimates, projections, assumptions and beliefs, which may prove to be incorrect. These risks and uncertainties include, but are not limited to: successful completion of the proposed FS and exploration and development programs referred to herein; the actual results of current and future exploration and development activities, liabilities inherent in exploration, mine development and production; geological, mining and processing technical problems; Auryx's inability to obtain required licenses, permits and regulatory approvals required in connection with exploration, mining and mineral processing operations; competition for, among other things, capital, acquisitions of resources, reserves, undeveloped lands and skilled personnel; incorrect assessments of the value of acquisitions; changes in commodity prices and exchange rates; currency and interest rate fluctuations; various events which could disrupt operations and/or the transportation of mineral products, including labour stoppages and severe weather conditions; the demand for and availability of rail, port and other transportation services; the availability of financing, and management's ability to anticipate and manage the foregoing factors and risks. There can be no assurance that forward-looking information will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Auryx undertakes no obligation to update forward-looking information if circumstances or management's estimates or opinions should change except as required by applicable securities laws. The reader is cautioned not to place undue reliance on forward-looking information.

Cautionary Note Concerning Resource Estimates

The mineral resource figures referred to in this press release are estimates and no assurances can be given that the indicated levels of gold will be produced. Such estimates are expressions of judgment based on knowledge, mining experience, analysis of drilling results and industry practices. Valid estimates made at a given time may significantly change when new information becomes available. While the Company believes that the resource estimates included in this press release are well established, by their nature resource estimates are imprecise and depend, to a certain extent, upon statistical inferences which may ultimately prove unreliable. If such estimates are inaccurate or are reduced in the future, this could have a material adverse impact on the Company. There is no certainty that mineral resources can be upgraded to mineral reserves through continued exploration.

Due to the uncertainty that may be attached to inferred mineral resources, it cannot be assumed that all or any part of an inferred mineral resource will be upgraded to an indicated or measured mineral resource as a result of continued exploration. Confidence in the estimate is insufficient to allow meaningful application of the technical and economic parameters to enable an evaluation of economic viability worthy of public disclosure, except in the case of the Preliminary Assessment. Inferred mineral resources are excluded from estimates forming the basis of a feasibility study.

Contact Information

  • Auryx Gold Corp.
    Andisheh Beiki
    Investor Relations
    +1 (416) 361-2213 or Mobile: +1 (647) 968-1920