Optimization Study Report for the Yanfolila Gold Project, Mali Prepared for: 22 Mount Row, London, W1K 3SF, UK Prepared by: 8301 E. Prentice Avenue, Suite 210 Greenwood Village, Colorado 80111 (303) 741-9633 Issue Date: February 17, 2015 TABLE OF CONTENTS 1.0 EXECUTIVE SUMMARY ................................................................................................. 1 1.1 Introduction .......................................................................................................... 1 1.2 Location ............................................................................................................... 1 1.3 Ownership............................................................................................................ 1 1.4 Climate and Physiography ................................................................................... 1 1.5 History ................................................................................................................. 3 1.6 Geological Setting ................................................................................................ 3 1.7 Deposit Types ...................................................................................................... 3 1.8 Exploration ........................................................................................................... 4 1.9 Mining .................................................................................................................. 4 1.10 Processing ........................................................................................................... 6 1.11 Infrastructure ........................................................................................................ 8 1.12 Environmental ...................................................................................................... 9 1.13 Project Economics ............................................................................................. 10 2.0 LOCATION AND CLIMATE .......................................................................................... 11 2.1 Climate and Environmental Conditions .............................................................. 11 2.1.1 Climate ................................................................................................................. 11 2.1.2 Geomorphology and Landscape .......................................................................... 11 2.1.3 Water Resources ................................................................................................. 11 2.2 Physiography ..................................................................................................... 11 3.0 GEOLOGY, MINERALIZATION, RESOURCE, AND EXPLORATION .......................... 13 3.1 Regional Geology .............................................................................................. 13 3.2 Resource Parameters ........................................................................................ 13 3.2.1 Interpolation Method (OK vs UC) ......................................................................... 13 3.2.2 Density ................................................................................................................. 13 3.2.3 Quality Assurance/Quality Control Review .......................................................... 14 3.2.4 Topography .......................................................................................................... 14 3.2.5 Komana East ........................................................................................................ 14 3.2.6 Komana West ....................................................................................................... 16 3.2.7 Guirin West .......................................................................................................... 18 3.2.8 Sanioumale West ................................................................................................. 20 3.2.9 Sanioumale East .................................................................................................. 21 3.3 Project Resource Statement .............................................................................. 23 3.4 Exploration ......................................................................................................... 25 3.4.1 Komana East - North Extension ........................................................................... 25 3.4.2 Gonka - Komana East Link .................................................................................. 25 3.4.3 Komana West - North Extension .......................................................................... 25 3.4.4 Komana West - South Extension ......................................................................... 25 3.4.5 Sanioumale East - Eastern Zone ......................................................................... 26 3.4.6 Soloba .................................................................................................................. 26 3.4.7 Kama .................................................................................................................... 26 4.0 MINING METHODS ....................................................................................................... 27 February 2015 i 4.1 Geotechnical Recommendations ....................................................................... 27 4.1.1 Background .......................................................................................................... 27 4.1.2 Recommendations ............................................................................................... 28 4.2 Hydrogeologic Studies ....................................................................................... 33 4.2.1 Pit Dewatering and Slope Depressurization ........................................................ 33 4.2.2 Waste Rock Disposal Facilities ............................................................................ 34 4.3 Mining Phase/Pit Designs .................................................................................. 35 4.3.1 Phase 3 Parameters ............................................................................................ 37 4.3.2 Shell and Phase Selection ................................................................................... 44 4.4 Contained Mineral Resource Estimates ............................................................. 44 4.5 Mine Production Schedule ................................................................................. 44 4.5.1 Mining Overview................................................................................................... 44 4.5.2 Scheduling Parameters ........................................................................................ 44 4.5.3 Mine Production Scheduling ................................................................................ 45 4.6 Mine Equipment ................................................................................................. 46 4.6.1 Equipment Selection and Operating Parameters ................................................ 46 4.6.2 Primary Mine Equipment ...................................................................................... 47 4.6.3 Auxiliary Equipment ............................................................................................. 48 4.7 Mine Workforce .................................................................................................. 48 4.7.1 Organization ......................................................................................................... 48 5.0 METALLURGY AND PROCESSING ............................................................................ 51 5.1 Introduction ........................................................................................................ 51 5.2 Metallurgical Testwork ....................................................................................... 52 5.2.1 Introduction .......................................................................................................... 52 5.2.2 Previous Testwork Campaigns ............................................................................ 52 5.2.3 Process Design .................................................................................................... 55 5.2.4 Ongoing Testwork Requirements ........................................................................ 60 5.2.5 Alternative Processing Scenarios ........................................................................ 63 5.3 Flowsheet Development ..................................................................................... 64 5.3.1 Introduction .......................................................................................................... 64 5.3.2 Crushing and Milling ............................................................................................ 65 5.3.3 Gold Recovery ..................................................................................................... 67 5.3.4 Gravity Recovery.................................................................................................. 68 5.3.5 Carbon in Leach (CIL) .......................................................................................... 68 5.3.6 Acid, Elution, Electrowinning, and Carbon Regeneration .................................... 70 5.3.7 Reagents .............................................................................................................