Flotation and Leaching at Anglo Asian Mining s Gedabek Gold and Copper Mine in Azerbaijan. A.J. Monhemius, F. Hedjazi & H.

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1 Flotation and Leaching at Anglo Asian Mining s Gedabek Gold and Copper Mine in Azerbaijan A.J. Monhemius, F. Hedjazi & H. Saeedi Ali Presentation at World Gold, COM 2017, Vancouver, August 2017

2 Disclaimer The information in this document is subject to updating, revision and amendment. This document neither constitutes nor forms nor should beconstructed as constituting or forming part of any offer or invitation to sell or any solicitation of any offer to purchase or to subscribe for any securities in Anglo Asian Mining PLC ( Anglo Asian Mining ) or any other body corporate or an invitation or inducement to engage in investment activity under section 21 of the UK Financial Services and Markets Act 2000 nor shall it or any part of it form the basis of or be relied on in connection with any contract therefore. This document does not constitute an invitation to effect any transaction with Anglo Asian Mining nor to make use of any services provided by Anglo Asian Mining. No reliance may be placed for any purpose whatsoever on the information contained in this document nor on assumptions made as to its completeness. No representation or warranty, express or implied, is given by Anglo Asian Mining, any of its subsidiaries or any of its respective advisers, officers, employees or agents, as to the accuracy, fairness or completeness of the information or opinions contained in this document or expressed in the presentation and, no liability is accepted for any such information or opinions (which should not be relied upon) or for any loss howsoever arising, directly or indirectly, from any use of this document or its contents or information expressed in the presentation. The information and opinions contained in this document and the presentation are provided as the date of this document and the presentation and are subject to change without notice. This presentation contains forward-looking statements that are based on Anglo Asian Mining's current expectations and estimates. Such forward-looking statements involve known and unknown risks, uncertainties and other factors that could cause actual events or results to differ materially from estimated or anticipated events or results implied or expressed in such forward-looking statements. Factors that could cause such difference include changes in world commodities and equity markets, political developments in Azerbaijan, changes to regulations affecting Anglo Asian Mining's activities and other risks involved in the mining industry. Any forward-looking statement speaks only as of the date on which it is made and Anglo Asian Mining disclaims any intent or obligation to update any forward-looking statement, whether as a result of new information, future events or results or otherwise. Forward-looking statements are not guarantees of future performance and, accordingly, undue reliance should not be put on such statements due to the inherent uncertainty therein. This presentation has been prepared in compliance with English law and English courts will have exclusive jurisdiction over any disputes arising from or connected with this presentation. 2

3 Azerbaijan Geography *Gedabek 3

4 Gedabek Ore Deposit q The Gedabek Cu/Au ore deposit is situated on the Tethyan Mineralisation Belt in the the Lesser Caucasus mountains at an altitude of 1600m. q It is a porphyry-type copper-gold deposit, believed to have been formed by two phases of mineralisation: (i) older volcanogenic massive sulphide (VMS) sulphide ore (ii) younger, highly weathered, porphyry stockwork oxide ore q It was originally worked by underground mining, mainly for copper, from about , by the Siemens company from Germany. The Germans left after the Bolshevik Revolution and mining in Gedabek then ceased for the remainder of the 20 th century. q Mining resumed again in 2009, when Anglo Asian started to rework the deposit by open pit methods, primarily for gold, with by-product copper and silver. 4

5 Gedabek Resources and Reserves q Current JORC compliant resource of 1.45 Moz of gold, 144Kton of copper and Moz of silver. (June 2014) q Mineable reserve of 744 Koz of gold, 59.5 Kton of copper and 6.18 Moz of silver. 5

6 Ore Mineralisation Sulphide Ore Minerals: q Pyrite (FeS 2 ) (dominant); Chalcopyrite (CuFeS 2 ) (frequent); Sphalerite (ZnS), Covellite (CuS), Chalcosite (Cu 2 S), Bornite (Cu 5 FeS 4 ), Galena (PbS), Arsenopyrite (FeAsS 2 ) (minor). Py/cpy = 12 to 15 Oxide Ore Minerals: q Malachite, Azurite (Cu(OH) x (CO 3 ) y ), goethite (FeOOH), other iron hydroxyoxides. Gold Minerals: q Native gold (Au), Electrum (Au/Ag), Petzite (Ag 3 AuTe 2 ), plus sub-microscopic gold in sulphide minerals Silver Minerals: q Native silver (Ag), Electrum (Au/Ag), Hessite (Ag 2 Te), Petzite (Ag 3 AuTe 2 ). 6

7 ADR 10 lit/m2 BLS SART Max=100m3/hr Thiourea H2 SO 4 Heat Heap leach Cu HL PLS Ag Loaded resin Elution 110 t/hr Crushing Grinding Ore from Mine CN Lime D80<70 mic ph>10 Air Agitation Leach RT= 48 hr Tailing Slurry RIP Stripped Resin Enriched Solution Electrowinning Barren Solution Leach THK Tailing THK Process Water %s =40% H 2 O 2 %s =45-50% Gold ALP Return Solution Tailing Dam

8 Grinding Process Water Leach THK Process Water to adjust the %S Screen Leach < 1mm S%= 40 Crusher 110 t/hr 5-10 cm SAG Ball Mill Tail Knelson Lime S%=65-70 Concentrate CN S%=42-45 AIR CN>2000 ph=10.5

9 Leaching Na CN Air Leach Thickener Slurry %Solid = 40-43% Flow = m3/hr D80 < 75 micron RIP Diameter = 11.5 m Height = 12 m Volume = 1100 m 3 Qty = 7 Total Retention Time = hr Total Capacity = 7700 m3 ~ 4300 ton solid

10 Resin-in-Pulp Fresh resin Loaded solution Heap leach Slurry Agitation Leach Resin > 1mm Solids < 100 micron Slurry Pump cell Slurry & Resin Total Capacity= 1200 m3 Total Retention Time = 4 hrs Diameter = 5.5m Height = 8.5 m Volume = 200 m 3 Resin volume = 6 m 3 Qty = 6 Tailing Thickener Loaded resin ADR % S = % Tailing Dam H 2 O 2 Tailing Solution SART / HEAP

11 Gedabek Gold Plant Capacity : 1 mt/y (ore) Production: 2 t/y (Au)

12 General View

13 Crusher

14 Grinding Ball mills SAG Hydrocyclones

15 Leach Tanks

16 Leach Tanks

17 RIP Pumpcells 17

18 SART Plant SART = Sulphidisation (S), Acidification (A), Recycling (R), Thickening (T) q Purpose of SART is to recover copper & silver (as sulphides) and recycle cyanide from gold leach solutions. q Main stages of the process are: (i) acidification and sulphidisation, (ii) copper sulphide precipitate thickening and filtration, (iii) neutralisation with lime, (iv) gypsum thickening and filtration.. 18

19 SART Process Flowsheet 19

20 Leaching followed by Flotation (L+F) Low Grade Ore Gedabek Open Pit Mine Cu/Au Flotation Concentate Flotation High Grade Ore Grinding Resin-in- Pulp O/F Grinding Thickener U/F Agitation Leach Plant U/F Tailings Thickener Loaded Resin ADR Eluted Resin O/F Gold Doré SART Cu/Ag Sulphide Concentrate PLS Pond BLS Pond Heap Leach Tailings slurry TMF Return water 20

21 Flotation followed by Leaching (F+L) Low Grade Ore Gedabek Open Pit Mine U/F Tailings Thickener High Grade Ore Grinding Resin-in- Pulp Cu/Au Flotation Concentrate O/F Grinding Thickener U/F Flotation Agitation Leach Plant O/F Loaded Resin Eluted Resin SART ADR PLS Pond BLS Pond Cu/Ag Sulphide Concentrate Gold Doré Heap Leach Tailings slurry TMF Return water 21

22 Location of Flotation Plant 22

23 Interior of Flotation Plant 23

24 Results and Recoveries for (L+F) Leaching plus Flotation (L+F) Ore Feed Rate Cyanide Consumption 2153 ton/day 4.54 kg/ton Grades Au (ppm) Ag (ppm) Cu (wt%) Ore feed Leach tails Flotation tails Recoveries Au (%) Ag (%) Cu (%) Agitation Leaching Flotation Overall

25 Results and Recoveries for (F+L) Flotation plus Leaching (F+L) Ore Feed Rate Cyanide Consumption 1843 ton/day 3.74 kg/ton Grades Au (ppm) Ag (ppm) Cu (wt%) Ore feed Flotation tails Leach tails Recoveries Au (%) Ag (%) Cu (%) Flotation Agitation Leaching Overall

26 Production Data for Concentrates Plant Configuration Concentrate Analyses Production Cu (wt%) Au (ppm) Ag (ppm) Rate (t/d) L + F SART Flotation F + L SART Flotation

27 Plant Configurations The plant is designed to be switched easily between (L+F) and (F+L) configurations. The decision on which scheme should be used is based on the economics of production, which is determined by the following factors: Metal grades (Au, Cu) in the ore; Metal prices; Recovery of each metal in the alternative schemes; Production cost of each scheme. 27

28 Conclusions Flotation of the Gedabek copper-gold ore ahead of cyanide leaching, compared with leaching before flotation, leads to:- q 20% increase in copper recovery q 18% decrease in cyanide consumption q Small increases in gold and silver recoveries The decreased cyanide consumption and increased metal recoveries have a significant effect on the process economics, leading to an increase in annual revenues of several million dollars. 28

29 ANY QUESTIONS? 29