Preliminary Results from Phase 2 Metallugical Testwork Received
(Thomson Reuters ONE) - UPDATE ON METALLUGICAL TESTS ON AFRICAN EAGLE'S DUTWA NICKEL PROJECT IN TANZANIA Preliminary Results from Phase 2 Metallugical Testwork Received* Initial column test results show rapid leach kinetics* Up to 70% nickel extraction after just 16 days acid leaching* Low acid consumption of 200-230 kg/tonne* Promising initial tank leach resultsAfrican Eagle's Managing Director Mark Parker comments, "Theseresults are extremely encouraging, showing very fast reactionkinetics and confirming the good nickel extraction and low acidconsumption of the Dutwa ores. The results show that the project isamenable to both heap leach and tank leach, and point the way tofurther tests to determine the optimum process parameters. The fastleaching reaction, low acid consumption and good nickel extractionare extremely positive indicators for the viability and profitabilityof the project."African Eagle has received interim results from the current phase ofmetallurgical testwork, which is being conducted by Mintek of SouthAfrica. The results include the first tank leach and column leachtest data, together with further "bottle roll" leach test results androck property test results.The test results will help to determine the best extraction processand to optimise parameters such as acid concentration, residence timeand leach temperature in the engineering design for the feasibilitystudy.Column testsThree column tests are being conducted to investigate the likelybehaviour of the ore under heap leach conditions. Coarsely crushedore (25mm or less in size) is packed into vertical plastic pipes, 1metre high and 200mm diameter, and continuously irrigated withsulphuric acid. The acid dissolves the nickel and other metals as itpercolates down the column.After only 16 days, 60% to 70% of the nickel had been extracted, withlow net acid consumption of 200 to 230kg/t. This shows extremelyfast leaching reaction kinetics, much faster than most publishednickel laterite data. Although column test data cannot be simplyscaled up to determine full-sized heap behaviour, these results areextremely encouraging.Fast reaction kinetics has important profitability implications forthe heap leach method, as it means that working capital will not betied up for many months while the heap reaches full productivity. AtCaldag in Turkey, for example, operator European Nickel plc reportsthat almost one year of leaching was required to extract 60% of thenickel from trial heaps and 540 days to extract 80%. Mintek reportsthat other nickel laterite ores it has column-tested have also takenmuch longer to achieve comparable recoveries.Tank leach testsThree tank leach tests have been conducted to investigate the orebehaviour under high temperature agitated vat leach conditions. Theore samples were pulverised to three different particles sizes forthese tests. The tests were conducted over 24 hours, but again, veryfast reaction kinetics was seen and almost all of the nickelextraction occurred within the first hour. The fast initial leachingexhausted the acid quickly and nickel extractions reached 64%, butfuture tests using higher initial acid concentrations should givebetter recovery.Bottle roll testsThree additional bottle roll tests were conducted to investigate theeffects of changing the acid concentration and the solids to liquidratio. The results showed that leaching efficiency falls if the acidconcentration is reduced.Physical property testsThe results of the following tests have also been received:* Bond impact work index* Bond abrasion index* Bond ball work index* Bond rod work index* Uni-axial compressive strength* Agglomerate stability tests* Bulk and true SG determination* Moisture content* Natural and complete sizingThe physical property test results will be used in the engineeringdesign for the feasibility study.Technical termsA glossary of technical terms used by African Eagle in thisannouncement and other published material may be found atwww.africaneagle.co.uk/p/glossary.aspFor further information:Mark ParkerManaging DirectorAfrican Eagle+44 20 7248 6059+44 77 5640 6899Nicola MarrinSeymour Pierce Limited, LondonNominated Adviser+ 44 20 7107 8000Charmane RussellRussell & Associates, Johannesburg+ 27 11 8803924+27 82 8928052Ed Portman / Leesa PetersConduit PR, London+44 20 7429 6607+44 77 3336 3501About African EagleAfrican Eagle is a diversified mineral exploration and developmentcompany operating in eastern and central Africa. The Company'sprincipal advanced assets are the Dutwa nickel laterite discovery inTanzania, where the Company completed a scoping study in June 2009,and its 49% interest in the Mkushi Copper Mines joint venture projectin Zambia, for which a draft feasibility study was completed in Q42008.African Eagle is evaluating a second promising nickel lateritedeposit at Zanzui in Tanzania and has defined a JORC gold resourceestimated at half a million ounces at its Miyabi gold project inTanzania. The Company holds a well-balanced portfolio of promisingearlier stage gold, copper, platinum and uranium projects, includingthe Ndola and Mokambo projects in the Zambian Copperbelt and theIgurubi gold project in Tanzania.Zambia, Tanzania and Mozambique, the sites of African Eagle'sprojects, are all countries which have highly prospective geology,relatively low above-ground risks and track records of successfulmajor investments in the metals and minerals industries.In December 2008, African Eagle resolved to prioritise the Dutwaproject, because the Board believes that, of all the Company'sprojects, it offered the greatest potential to add value. To take itsother discoveries into production, African Eagle is seeking industrypartners with records of successful mine development, by means ofjoint ventures, farm-ins, spin-outs or other mechanisms.About the Dutwa ProjectAfrican Eagle has discovered a significant nickel laterite deposit inthe Dutwa project area in the Lake Victoria Goldfield. WithinTanzania, the project is favourably situated 100km east of therailhead at Mwanza and close to the main Mwanza-Nairobi trunk road, amajor power line and the shore of Lake Victoria.The Company holds a 90% interest, with option to acquire 100%, overthe Dutwa laterite deposit and in 2009, signed a Letter of Intent foran option and joint venture over another nickel laterite at Ngasamo,5km west. In all, African Eagle has explored a total area of morethan 750km² in the project area.Since the discovery of the Dutwa nickel deposit in June 2008, AfricanEagle has explored the project very quickly and cost-effectively,including resource drilling and an independent resource estimate;laboratory metallurgical and mineralogical tests which revealed thatthe deposit could be processed efficiently by sulphuric acidleaching. On 24 June 2009, the Company announced the results of its"proof of concept" scoping study. The study, by GRD Minproc of Perth,Western Australia, indicated that the project can be economicallyviable, and African Eagle has now begun work towards a definitivefeasibility study.The Study indicates that Dutwa, if it were in production today, wouldbe profitable. Earnings, on an EBIT basis, would be of the order of$110 million per annum on average over the life of mine, giving aninternal rate of return around 20%.As a potentially low-cost producer, the upside for the Dutwa projectis considerable if nickel prices are above the $7/lb used in the basecase. The following table shows the key metrics for several upsidecases.Ni price US$/lb 9.00 8.50 8.00 7.50 7.00 6.50Life of mine EBIT $M 2,600 2,300 2,000 1,800 1,500 1,200Pre-tax IRR % 31 27 24 21 17 13Post-tax IRR % 27 24 21 18 15 11Pre-tax NPV $M 640 530 420 310 200 90Post-tax NPV $M 430 350 270 190 110 30Base case: Abbreviations:Nickel price = US$ 7/lb ($15,430/tonne) EBIT = Earnings beforeCobalt price = US$ 10/lb interest and taxDiscount rate = 10% IRR = Internal Rate ofTransport cost = US$100/tonne Return(8¢/tonne/km) NPV = Net Present ValueTax rate = 30%, fiscal incentives not DCF = Discounted cash flowaccounted analysisRoyalty = 3% All numbers stated to 2The financial modelling was conducted in significant digitsUS dollars with an estimated accuracy of±30%The Study adopted a fairly broad brush approach to many of the costs,to demonstrate "proof of concept" and provide indicative economics.GRD Minproc estimated individual capital and operating costs to ±30%, based on their considerable experience with nickel laterites.These variables will be determined with more accuracy and confidenceduring the forthcoming feasibility work.The Study identified several key areas where further testwork anddetailed study are especially likely to result in improvements to the"bottom line" or to important gains in confidence. These areasinclude:* Improved global deposit model and the potential for early "high-grading". The Ngasamo resource will be drilled and incorporated into a more sophisticated global resource model and mining plan. From this, it will be possible to establish whether richer ore can be mined first, giving increased early cash-flow and an improved NPV.* Ore beneficiation and project scale. The capital and operating costs of the plant would be reduced if mechanical beneficiation of the ore prior to leaching yields a smaller tonnage of richer material for processing through the plant.* Advanced leaching testwork. Column and vat leach tests at bench and pilot scale will determine the best operating conditions to optimise nickel extraction, including acid concentration, residence time and temperature.* Reagent cost reductions. The cost of reagents, notably sulphur and lime, will be a significant component of operating costs and profitability will increase considerably if these costs are minimised. Transport is a substantial part of the reagent costs and ways to minimise this will be investigated, as will the availability of more local sources, particularly of lime.* More sophisticated fiscal and economic modelling. Tanzania offers a number of tax incentives for exploration and mine development, which were not fully accounted in the Study economic model.In August, the Company raised £3.3M additional capital through aPlacing and Offer, to address these issues and progress the projecttowards feasibility. Further metallurgical testing has commenced ondrill core samples at Mintek laboratories in South Africa and theCompany has started infill drilling at Dutwa and resource drilling atNgasamo.African Eagle acquired the Dutwa project for its gold potential, butthe Company's exploration team quickly recognised that there wassignificant nickel laterite potential. There is very little outcrop,so the Company conducted extensive ground magnetic surveys to revealthe underlying structure and geology. The Company also compiledhistorical data, including detailed geological maps and trenchresults dating from 1956, when rock chip samples from the trenchesover the ultramafic rocks were reported as yielding up to 1.9%nickel.Greenstones and granites underlie the project area. The greenstones,of Archaean Nyanzian age, are mostly metamorphosed volcanic andsedimentary rocks, with some banded iron formation in the east.Several large ultramafic bodies occur within the greenstones and thenickel laterites form a blanket up to 60m thick on top of these.To investigate the nickel discovery, the Company undertook trialdrilling in June 2008. The results were very encouraging and a139-hole reverse circulation (RC) drilling programme was completed todelineate the resource. African Eagle also undertook a 10-holediamond drill programme to obtain core samples for metallurgicaltesting and density measurements.In November 2008, African Eagle announced an initial Inferred MineralResource estimate of 31 million tonnes at an average grade of 1.1%nickel and 0.034% cobalt. At a cut-off grade of 0.5% nickel, thisgives Dutwa a contained metal endowment of some 340,000 tonnes ofnickel and 11,000 tonnes of cobalt. The estimate was prepared byindependent consultants SRK Consulting (UK) Ltd in line with theAustralasian Code for Reporting of Mineral Resources and Ore Reserves(the JORC Code). A little additional drilling and more advancedgeostatistics and deposit modelling will be needed to upgrade theresource to Indicated category.Ngasamo Hill, 5km west of the Dutwa deposit, is geologically verysimilar and holds a laterite deposit of the order of 15 to 20 milliontonnes, which would increase the global resource at Dutwa from thecurrently defined 31 million tonnes at 1.1% nickel, to some 45 - 50million tonnes. Drilling and metallurgical tests will be needed toconfirm the size, grade and compatibility of Ngasamo. Under itsagreement with Ngasamo's owners, (Safina a.s. of the Czech Republicand its Tanzanian subsidiary Precious Metals Refinery Company Ltd),African Eagle can earn an interest of at least 50% and up to 75% inNgasamo by carrying out exploration and evaluation work, up to afeasibility study.Mintek Laboratories in Johannesburg investigated the mineralogy andmetallurgy of mineralised drill samples from the deposit, includingextended 'bottle roll' sulphuric acid leach tests to investigatemetal recoveries and acid consumption. Mintek also carried outmineralogical characterisation by X-ray diffraction (XRD), scanningelectron microscopy (SEM) and polished section work.The bottle roll test results showed nickel extractions of 70-90% withan average of 83%. Cobalt extractions were mostly in the range 70 to85%. The acid consumptions, averaging 209kg/t, are very low comparedto other Ni laterite ores worldwide.The mineralogical investigations show that the laterite is extremelysilica-rich, with low iron and magnesium content, indicating thatDutwa is not a typical laterite nickel deposit. Mintek believes thatmuch of the nickel and cobalt occurs in "wad" with manganese contentof 20-60%, nickel content of up to 20% and cobalt content of up to10%.The unusual mineralogy of the deposit is highly beneficial, as itresults in lower acid consumption and is expected to give good heapleach permeability or favourable liquid-solid separation in tankleaching. The concentration of nickel and cobalt in the manganese wadoffers the possibility that mechanical selection of high-gradematerial may allow reduced throughput and hence a lower costprocessing plant.The Company is also investigating other potential nickel lateritedeposits in Tanzania, and has completed a trial programme of RCdrilling to test a laterite at its Zanzui project, 60km to the southof Dutwa. Results included 42m at 1.05% nickel (including 6m at2.80%) and 33m at 0.91% nickel (including 9m at 1.41%).---END OF MESSAGE---This announcement was originally distributed by Hugin. The issuer is solely responsible for the content of this announcement.
Datum: 01.12.2009 - 08:01 Uhr
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