2317-RPT-003 Revision Number 0
Lumina Copper Corp Taca Taca Copper/ Gold Molybdenum Project
Preliminary Economic Assessment Report Date of Report: May 24, 2013
Effective Date: April 9, 2013
QUALIFIED PERSONS:
Scott C. Elfen, P. E. Robert Sim, P. Geo. Bruce M. Davis, FAusIMM William L. Rose, P. E. Kevin Scott, P. Eng. (Principal)
Prepared by: Prepared for:
855 Homer Street Vancouver, BC V6B 2W2 Canada
Table of Contents 1 Summary 1 1.1 Introduction 1 1.2 Project Location 2 1.3 Property Ownership 2 1.4 Property Description 4 1.5 Geology and Mineralization 5 1.6 Drilling 5 1.7 Mineral Resource 5 1.8 Mining 6 1.9 Mineral Reserve Estimate 8 1.10 Metallurgical Testing 8 1.11 Process Design and Recovery 8 1.12 Execution Plan and Schedule 9 1.13 Capital Cost 9 1.14 Operating Cost 10 1.15 Marketing Studies 11 1.16 Economic Evaluation 12 1.17 Interpretations and Conclusions 15 1.18 Recommendations 16 1.19 Cautionary Note Regarding Forward-Looking Information and Statements 17 2 Introduction 21 2.1 Purpose of the Technical Report 21 2.2 Sources of Information 21 2.3 Personal Inspection of the Taca Taca Project 22 2.4 Currency Assumptions 22 3 Reliance on Other Experts 23 4 Property Description and Location 24 4.1 Property Location 24 4.2 Property Ownership and Agreements 24 4.3 Environmental Liabilities and Permitting 29 4.4 Other Significant Factors and Risks Affecting Access or Title 29 5 Accessibility, Climate, Local Resources, Infrastructure, & Physiography 30 5.1 Location and Access 30 5.2 Physiography and Vegetation 30 5.3 Climate and Topography 30 5.4 Local Resources 30 5.5 Regional Infrastructure 31 6 History 32 7 Geological Setting and Mineralization 34 7.1 Regional Geology 34 7.2 Local and Property Geology 36 7.3 Mineralization 38 7.4 Structure 44 8 Deposit Types 46 9 Exploration 47
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9.1 Historic Exploration Programs (Non-Drilling) 47 9.2 Exploration by Lumina Copper (2010 - 2012) 47 10 Drilling 49 10.1 Drilling 49 10.2 Historic Drilling 50 10.3 Drilling by Lumina Copper (2010-2012) 51 11 Sample Preparation, Analyses, and Security 53 11.1 Historic Drilling and Sample Preparation 53 11.2 Lumina Copper Drilling (2010-2012) 56 12 Data Verification 65 12.1 Historic Drilling 65 12.2 Lumina Copper Drilling 65 12.3 Conclusions 66 13 Mineral Processing and Metallurgical Testing 67 13.1 General 67 13.2 Metallurgical Testing 67 13.3 Comminution Test Work 69 13.4 Flotation Test Work 70 13.5 Sedimentation and Filtration Test Work 82 14 Mineral Resource Estimates 84 14.1 Introduction 84 14.2 Geologic Model, Domains, and Coding 84 14.3 Available Data 86 14.4 Compositing 90 14.5 Exploratory Data Analysis 91 14.6 Bulk Density Data 94 14.7 Evaluation of Outlier Grades 95 14.8 Variography 96 14.9 Model Setup and Limits 97 14.10 Interpolation Parameters 98 14.11 Validation 99 14.12 Resource Classification 105 14.13 Mineral Resources 106 14.14 Comparison with Previous Resource Estimate 111 14.15 Discussion of Factors Materially Affecting Mineral Resources 114 15 Mineral Reserve Estimates 115 16 Mining Methods 116 16.1 Economic Pit Limit Evaluations 116 16.2 Mining Phase/Pit Designs 118 16.3 Mine Production Schedule 120 16.4 Waste Rock Storage and Stockpiling 124 16.5 Mine Equipment 125 16.6 Mine Workforce 128 17 Recovery Methods 129 17.1 Introduction 129 17.2 Process Design Basis and Design Criteria Summary 129 17.3 Flow Sheet Development and Equipment Sizing 130 17.4 Comminution Circuit Design 133
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17.5 Bulk Copper-Molybdenum Flotation Circuit Design 134 17.6 Copper-Molybdenum Separation and Molybdenum Cleaning 135 17.7 Copper Concentrate Thickening and Filtration 136 17.8 Molybdenum Concentrate Thickening and Filtration 136 17.9 Concentrate Rail Load-Out Facility 136 17.10 Tailings Processing 136 17.11 Brine, Desalinated, and Process Water 137 17.12 Reagents 137 17.13 Plant Layout & Description 137 18 Project Infrastructure 139 18.2 Roads 139 18.3 Power Supply 144 18.4 Site Electrical Power Distribution 146 18.5 Tailings Storage Facility 146 18.6 Reclaim Water System 149 18.7 Hydrogeology and Raw Water Supply Sources 149 18.8 Process Water Supply 151 18.9 Potable Water 154 18.10 Logistics and Transportation 154 18.11 Concentrate Storage, Handling, and Transport 159 18.12 Ancillary Site Buildings and Facilities 165 18.13 Permanent Camp 165 19 Market Studies and Contracts 167 19.1 Introduction 167 19.2 Supply and Demand 167 19.3 Smelter Capacities and Utilization 167 19.4 Ocean Freight 168 19.5 Future Metals Pricing 168 20 Environmental Studies, Permitting, and Social or Community Impact 169 20.1 Environmental Baseline 169 20.2 Permitting 170 20.3 Conceptual Closure 170 20.4 Socioeconomic Conditions 173 21 Capital and Operating Costs 177 21.1 Capital Cost Estimate 177 21.2 Estimate Exclusions 178 21.3 Basis of Estimate – Mining 178 21.4 Basis of Estimate – Process and Infrastructure Direct Costs 178 21.5 Basis of Estimate – Indirect Costs 179 21.6 Owner’s Costs 179 21.7 Other Costs – Freight, Duties & Taxes 180 21.8 Contingency 180 21.9 Accuracy 181 21.10 Initial Capital 181 21.11 Operating Costs 182 21.12 Basis of Estimate 183 21.13 Mining Operating Costs 183 21.14 Process Operating Costs 184 21.15 Infrastructure Maintenance 185 21.16 Railroad Operation 186
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21.17 General and Administrative 186 21.18 Mine Reclamation 187 21.19 C-1 Cash Costs (net of credits) 187 22 Economic Analysis 189 22.1 General Criteria 189 22.2 Production Summary 190 22.3 Gross Income from Mining 191 22.4 Net Smelter Revenue (NSR) Calculation 192 22.5 Royalty Calculation 193 22.6 Operating Margin 193 22.7 Retention Taxes 193 22.8 Depreciation and Income Tax 193 22.9 Initial Capital Costs 195 22.10 Sustaining Capital Costs 195 22.11 Working Capital 197 22.12 Base Case Analysis 198 22.13 Base Case Sensitivity Analysis 198 22.14 Economic Model 201 23 Adjacent Properties 204 24 Other Relevant Data and Information 205 25 Interpretations and Conclusions 206 25.1 Interpretations and Conclusions 206 25.2 Risks and Opportunities 207 26 Recommendations 210 27 References 212 28 Date and Signature Page 215
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List of Figures
Figure 1-1: Property Location Map (Afrainlle, June 2012) ...... 2 Figure 1-2: Taca Taca Property ...... 4 Figure 1-3: IRR Sensitivity Analysis – Metal Prices ...... 14 Figure 1-4: NPV Sensitivity Analysis – Metal Prices ...... 14 Figure 4-1: Property Location Map (Afrainlle, June 2012) ...... 24 Figure 4-2: Claim Map ...... 27 Figure 7-1: Regional Geology (Almandoz, 2008) ...... 35 Figure 7-2: Surface Geology of the Taca Taca Project (Almandoz, 2008) ...... 36 Figure 7-3: Paragenesis of Mineralization at Taca Taca (Almandoz, 2008) ...... 39 Figure 7-4: Extent of Hypogene Sulphide Mineralization (Wells, 2012) ...... 40 Figure 7-5: Vertical East-West Oriented Cross Section 728 3950 N (Wells, 2012) ...... 41 Figure 7-6: Extent of Supergene Enrichment Zone (Wells, 2012) ...... 42 Figure 7-7: Extent of Gold in Leach Cap (Wells, 2012) ...... 43 Figure 7-8: Hematite Copper-Gold Veins (Wells, 2012) ...... 44 Figure 9-1: Titan 24 IP and MT Anomalies (Sim, 2011) ...... 48 Figure 10-1: Drill Collar Plan Map – Taca Taca Project (Wells, 2012) ...... 50 Figure 11-1: ALS Chemex OREAS 50C SRM Copper Control Chart ...... 59 Figure 11-2: ALS Chemex OREAS 50C SRM Gold Control Chart ...... 59 Figure 11-3: ALS Chemex OREAS 50C SRM Molybdenum Control Chart ...... 60 Figure 11-4: ALS Chemex Coarse Blank Copper Control Chart ...... 60 Figure 11-5: ALS Chemex Copper Coarse Duplicate Comparisons ...... 61 Figure 11-6: Alex Stewart OREAS 503 SRM Copper Control Chart ...... 62 Figure 11-7: Alex Stewart OREAS 503 SRM Gold Control Chart ...... 62 Figure 11-8: Alex Stewart OREAS 503 SRM Molybdenum Control Chart ...... 63 Figure 11-9: Alex Stewart Coarse Blank Copper Control Chart ...... 63 Figure 11-10: Alex Stewart Copper Coarse Duplicate Comparisons ...... 64 Figure 13-1: Copper Recovery vs Copper Feed Grade, Roughers – Supergene (Plenge, 2012) ...... 73 Figure 13-2: Molybdenum Recovery vs Molybdenum Feed Grade, Roughers – Supergene (Plenge, 2012) ...... 74 Figure 13-3: Copper Recovery vs Copper Feed Grade, Roughers – Primary (Plenge, 2012)...... 75 Figure 13-4: Molybdenum Recovery vs Molybdenum Feed Grade, Roughers – Primary (Plenge, 2012) ...... 76 Figure 13-5: Copper Recovery vs Copper Feed Grade, Cleaners – Supergene (Plenge, 2012) ...... 77
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Figure 13-6: Molybdenum Recovery vs Molybdenum Feed Grade, Cleaners – Supergene (Plenge, 2012) ...... 78 Figure 13-7: Copper Recovery vs Copper Feed Grade, Cleaners – Primary (Plenge, 2012) ...... 79 Figure 13-8: Molybdenum Recovery vs Molybdenum Feed Grade, Cleaners – Primary (Plenge, 2012) ...... 80 Figure 14-1: Isometric Views of MinZone Domains (Sim, 2013) ...... 86 Figure 14-2: Distribution of Copper Grades in Drill Holes (Sim, 2013) ...... 88 Figure 14-3: Distribution of Additional Sample Data since the April 2012 Resource Estimate (Sim, 2013) ...... 89 Figure 14-4: Box Plot Copper by MinZone Domain ...... 92 Figure 14-5: Contact Profiles Copper between LX and SS MinZones ...... 93 Figure 14-6: Contact Profiles Copper between SS and PR MinZones ...... 93 Figure 14-7: Herco Copper in SS Zone ...... 100 Figure 14-8: Herco Copper in PR Zone ...... 101 Figure 14-9: GT Comparison of OK, IDW, and NN Copper Models ...... 102 Figure 14-10: GT Comparison of OK, IDW, and NN Molybdenum Models ...... 102 Figure 14-11: GT Comparison of OK, IDW, and NN Gold Models ...... 103 Figure 14-12: Copper Model Swath Plot by Easting ...... 104 Figure 14-13: Copper Model Swath Plot by Northing ...... 104 Figure 14-14: Copper Model Swath Plot by Elevation ...... 105 Figure 14-15: Plan Map Showing Limit of Porphyry Type Mineralization (Sim, 2013) ...... 106 Figure 14-16: Extents of Base Case Indicated and Inferred Copper Resources (Sim, 2013) ...... 109 Figure 14-17: Extents of Base Case Resources Including LX Zone Gold Resource (Sim, 2013) ...... 109 Figure 14-18: Changes to Base Case Indicated Resources Nov 2012 vs. April 2012 (Sim, 2013) ...... 113 Figure 14-19: Changes to Base Case Indicated & Inferred Resources Nov 2012 vs. April 2012 (Sim, 2013) ...... 113 Figure 16-1: Ultimate Pit Design (WLRC, 2013) ...... 120 Figure 16-2: Waste Rock Storage and Oxide Stockpile Facilities (WLRC, 2013) ...... 125 Figure 17-1: Overall Process Flow Diagram ...... 131 Figure 17-2: Pebble Crushing – Mill Building Plan and Elevations ...... 138 Figure 18-1: General Mine Access Road (Ausenco, 2013) ...... 140 Figure 18-2: Mine Access Road (Ausenco, 2013) ...... 141 Figure 18-3: Out of Pit Haul Roads (Ausenco, 2013) ...... 143 Figure 18-4: Transmission Line Routing from Olacapato to Taca Taca (Hugo Gil, 2013) ...... 145 Figure 18-5: Tailings Discharge System – Jacking Headers ...... 148 Figure 18-6: Exit from the Project along Ruta 27 and Access to Ruta 51 to Paso Sico (TUSA, 2011) 157
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Figure 18-7: Travel from Paso Sico to Antofagasta through Lacos, Socaine, and Peine (TUSA, 2011) ...... 158 Figure 18-8: Travel from Paso Sico, to San Pedro de Atacama and Calama, arriving to Antofagasta (TUSA, 2011) ...... 158 Figure 18-9: Map of Railway Routes between Taca Taca and Mejillones (TFP, 2013) ...... 160 Figure 18-10: Site Layout ...... 161 Figure 21-1: Percentage of Processing Costs by Component ...... 185 Figure 21-2: C-1 Cash Costs Net of Credits ...... 188 Figure 22-1: IRR Sensitivity Analysis – Metal Prices ...... 199 Figure 22-2: NPV Sensitivity Analysis – Metal Prices ...... 199 Figure 22-3: IRR Sensitivity Analysis – Capital v Operating Costs ...... 200 Figure 22-4: NPV Sensitivity Analysis – Capital v Operating Costs ...... 200 Figure 22-5: IRR Sensitivity Analysis – Metallurgical Recovery ...... 200 Figure 22-6: NPV Sensitivity Analysis – Metallurgical Recovery ...... 201 Figure 22-7: Cash Flow Model Forecast ...... 202
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List of Tables
Table 1-1: Mineral Resource Summary ...... 6 Table 1-2: Capital Cost Summary ...... 9 Table 1-3: Operating Cost Summary ...... 10 Table 1-4: Metal Price Forecast ...... 12 Table 1-5: Project Metals Pricing ...... 12 Table 1-6: Economic Model Inputs ...... 12 Table 1-7: Net Present Value with Mid-Period Adjustment ...... 14 Table 1-8: Estimated Cost for Recommended Future Work ...... 16 Table 4-1: Mining Concessions ...... 25 Table 6-1: Exploration and Ownership History of the Taca Taca Project ...... 32 Table 10-1: Drilling History ...... 49 Table 13-1: Summary of Comminution Test Results ...... 69 Table 13-2: Summary of SAGDesign® Results ...... 69 Table 13-3: JKTech – SMC Test Results ...... 70 Table 13-4: Summary of Locked Cycle Tests Using Tap Water ...... 70 Table 13-5: Locked Cycle Tests on Composites Comparing Use of Brine Water and Tap Water in Roughers ...... 71 Table 13-6: Variability Rougher Test – Supergene ...... 72 Table 13-7: Variability Rougher Tests – Primary ...... 74 Table 13-8: Variability Cleaner Tests – Supergene ...... 76 Table 13-9: Variability Cleaner Tests – Primary ...... 78 Table 13-10: Batch Cleaner Test Results at Different Water Quality Blends ...... 80 Table 13-11: Summary of Brine Water Analyses ...... 81 Table 13-12: Copper Concentrate Sedimentation Results ...... 82 Table 13-13: Tailings Sedimentation Results ...... 82 Table 13-14: Filtration Results for Locked Cycle Test Copper Concentrates ...... 82 Table 14-1: MinZone Domains and Coding ...... 85 Table 14-2: Basic Summary of All Sample Data ...... 90 Table 14-3: Basic Summary of Sample Data Proximal to the Resource Model ...... 90 Table 14-4: Summary of Interpolation Domains ...... 94 Table 14-5: Summary of Bulk Density by MinZone Domain ...... 95 Table 14-6: Summary of Outlier Limits ...... 95 Table 14-7: Variogram Parameters - Copper ...... 96
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Table 14-8: Variogram Parameters - Molybdenum ...... 97 Table 14-9: Variogram Parameters - Gold ...... 97 Table 14-10: Block Model Limits ...... 98 Table 14-11: Interpolation Parameters ...... 99 Table 14-12: Supergene and Primary Sulphide Zone Mineral Resource Estimate ...... 107 Table 14-13: Leach Zone Oxide Mineral Resource Estimate ...... 108 Table 14-14: Copper Mineral Resource Estimate by Type ...... 110 Table 14-15: Comparison of Copper Mineral Resources – April 2012 vs. Nov 2012 ...... 111 Table 14-16: Comparison of Leach Zone Mineral Resources – April 2012 vs. Nov 2012 ...... 112 Table 16-1: Floating Cone Recovery and Economic Parameters ...... 116 Table 16-2: Basic Pit Design Parameters ...... 119 Table 16-3: Pit Design Recommendations ...... 119 Table 16-4: Production Scheduling Parameters ...... 121 Table 16-5: Geologic Zones and Bulk Densities ...... 122 Table 16-6: Taca Taca Mine Production Schedule ...... 123 Table 16-7: Resource Classification of Concentrator Feed – PEA Schedule ...... 124 Table 16-8: Mine Equipment Fleet for Selected Years ...... 127 Table 16-9: Projected Mine Workforce for Selected Years ...... 128 Table 17-1: Summary of Key Process Design Criteria ...... 129 Table 17-2: Mill Design Criteria ...... 133 Table 17-3: Summary of Reagent Consumption ...... 137 Table 18-1: Components of 600 l/s of Untreated Brine Water Make-Up ...... 152 Table 18-2: Components of 200 l/s of Fresh Water Make-Up...... 152 Table 18-3: Estimated Permeate and Concentrate Chemistry ...... 153 Table 18-4: Camp Arrangement ...... 166 Table 19-1: Metal Price Forecast ...... 168 Table 19-2: Project Metals Pricing ...... 168 Table 21-1: Mine Capital Cost Summary ...... 177 Table 21-2: Labour Hourly Rates ...... 179 Table 21-3: Brownfield Productivity Factors ...... 179 Table 21-4: Freight Applied to Material/Equipment Cost ...... 180 Table 21-5: Summary of Initial Capital Costs ...... 181 Table 21-6: LOM Operating Cost Summary ...... 182 Table 21-7: Main Operating Cost Assumptions ...... 183
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Table 21-8: LOM Operating Cost Summary - Mining ...... 184 Table 21-9: LOM Operating Cost Summary - Process ...... 184 Table 21-10: Derivation of Plant Operating Estimate ...... 185 Table 21-11: LOM Operating Cost Summary – Infrastructure Maintenance ...... 186 Table 21-12: LOM Operating Cost Summary – Railroad Operation ...... 186 Table 21-13: LOM Operating Cost Summary – G&A ...... 187 Table 21-14: Average LOM C-1 Cash Costs ...... 188 Table 22-1: Economic Model Inputs ...... 189 Table 22-2: Process Production Summary ...... 190 Table 22-3: Calculation of Gross Revenue ...... 192 Table 22-4: TCs, RCs, and Freight ...... 192 Table 22-5: Deduction of Capitalized Costs to Date ...... 194 Table 22-6: MIL Section 13 Depreciation ...... 194 Table 22-7: Sustaining Capital Cost Summary ...... 196 Table 22-8: Sustaining Capital for Concentrator Expansion ...... 197 Table 22-9: Net Present Value with Mid-Period Adjustment ...... 198 Table 22-10: Sensitivity Analysis of IRR and NPV ...... 198 Table 26-1: Estimated Cost for Recommended Future Work ...... 210
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Nomenclature and Abbreviations
Abbrev. Description Abbrev. Description A Ampere MCC Motor control centre Bt Billions tonnes MIBC Methyl isobutyl carbinol C Celsius, as in degrees, °C min Minute cm Centimetre mg Milligrams CSS Closed side setting mg/l Milligrams per litre Cu Copper mm Millimetre d Day Mt Million tonnes dmt Dry metric tonne Mt/y Million tonnes per year Engineering, procurement and EPCM MPa Megapascal construction management Fe Iron MVA Megavolt-ampere FEL Front-end loader MW Megawatt g Gram NQ Drill core size (about 47.5 mm) g/l Grams per litre PLC Programmable logic controller g/mol Mole mass, in grams ppb Parts per billion g/t Grams per tonne ppm Parts per million (equivalent to g/t) h Hour PAX Potassium amyl xanthate ha Hectare P80 Size at which 80% (mass) is finer HP Horsepower ROM Run-of-mine HQ Drill core size (about 63.5 mm) s Second k Kilo or thousand SAG Semi-autogenous grinding Supervisory, Control and Data kg Kilogram SCADA Acquisition kg/m3 Kilogram per cubic metre SG Specific gravity km Kilometre t Tonne km2 Square kilometre t/d Tonnes per day kPa Kilopascal t/h Tonnes per hour kV Kilovolt t/y Tonnes per year kVA Kilovolt-ampere TSF Tailings storage facility kW Kilowatt (power) V Volt kWh Kilowatt-hour WRSF Waste rock storage facility l Litre wmt Wet metric tonne m Metre y Year M Mega or million µm Micrometre or micron m2 Square metre Approximately ° Degrees
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1 Summary
1.1 Introduction
The Taca Taca Project (the Project) is a porphyry copper-gold-molybdenum deposit located in northwestern Argentina in the Puna (Altiplano) region of Salta Province. The Project is beneficially owned by Lumina Copper Corp. (Lumina Copper), based in Vancouver, British Columbia, Canada. It is approximately 230 km west of the city of Salta and 55 km east of the Chilean border (Figure 1- 1).
The Project envisages a mine operating over a 28-year life delivering 120,000 t/d of throughput (for an initial period of seven years) to a concentrator comprising two milling and flotation lines. An expansion of the concentrator through the addition of a third line is contemplated to increase the total throughput to 180,000 t/d from Year 8 onwards.
While the Project is remote, there is good regional infrastructure. A network of paved and gravel roads from Salta to the towns of San Antonio de los Cobres and Tolar Grande provide access to the Project. The road continues west beyond the Project to the Socompa Pass on the Chilean border and eventually to the port city of Antofagasta, Chile.
The Project is located within 10 km of the railway line that connects Salta with Antofagasta. This rail infrastructure will be used to transport concentrates and select consumables to and from the Port of Mejillones, 65 km north of Antofagasta and other consumables from within Argentina.
Electrical power connection to the national power grid is available in the region at Olacapato to the north of the Project and a 345 kV transmission line over a length of 144 km is proposed to provide electrical power to the Project.
Although the region is arid, subsurface water is available in the local area. A water supply study and water balance analysis were completed for the Project and based on these studies, the processing water flow sheet shows that there are adequate sources of water available for the Project. Additional prospective areas have recently been identified near the Project that may be sources of additional fresh water, which could further optimize the process water flow sheet.
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Figure 1-1: Property Location Map (Afrainlle, June 2012)
1.2 Project Location
The Project is located in the Puna (Altiplano) region of Salta Province, northwest Argentina at an elevation of 3,585 meters above sea level (masl). It is approximately 230 km west of the city of Salta. The centre of the property is at latitude 24.7oS and longitude 68.0oW. The UTM coordinates are 7283500 N and 2628000 E (geographic projection: Gauss-Kruger POSGAR 94/Argentina WGS84, Zone 2).
1.3 Property Ownership
The Project consists of the Grupo Minero Taca Taca concession (Grupo Minero) that covers 2,559.96 ha, and 27 additional mining (mina) and exploration (cateo) concessions and one land use application, owned wholly or in part, that covers 58,001.32 ha. In the region, one land use application, one additional mining concession application, and two additional exploration concession applications have been registered, but not yet granted; these total 3,291.95 ha. The mining properties and rights comprising the Project, including the applicable file numbers, area,
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status, and contractual royalty encumbrances are listed in and shown in Table 4-1 and are shown in Figure 4-2 as part of a detailed discussion in Item 4.0.
The Grupo Minero concessions are maintained through annual fees (canon) which at current official exchange rates are equivalent to $4,410 per year. The remaining concessions have an annual canon fee of $23,360. One-half of the total annual canon fees ($13,885) are paid semi-annually in June and December.
As of May 2, 2013, all of the mining and exploration concessions were in good standing and canon fees have been paid through June 30, 2013. The Grupo Minero and other concessions are valid for an unlimited period of time as long as the semi-annual canon payments are made. All exploration concessions will have to be converted to mine properties in 2013 and 2014. The Grupo Minero and other mining concessions include the right to exploit, subject to being granted by an environmental permit for exploitation. The exploration concessions include the right to explore for all metals or minerals.
The surface lands covering the Project are owned by the Province of Salta and the necessary access permits were granted for the current drilling work. All known mineralized zones are located hundreds of metres within the limits of the Project boundaries.
The Grupo Minero and other mining and exploration concessions are registered under the name Corriente Argentina S.A. (CASA) except for Mina Don Francisco which is held in trust for CASA by S. Arbeleche and Mina Francisco 1 and Mina Francisco 2 which are jointly owned through a company 50% owned by CASA and 50% owned by Salta Exploraciones S.A. (SESA). Lumina Copper is the beneficial owner of all of the issued and outstanding shares of CASA. A member of Lumina Copper management holds approximately 1.0% of the issued and outstanding shares in the capital of CASA in trust for the benefit of Lumina Copper in order to address certain requirements applicable to Argentinian companies under Argentine corporate law.
Lumina Copper first acquired an interest in the Taca Taca property when shareholders of Global Copper Corp. (Global Copper) approved a corporate reorganization effective August 1, 2008 by way of a statutory plan of arrangement (Global Arrangement); pursuant to the Global Arrangement, Teck Resources acquired all Global Copper’s shares. Global Copper’s assets, excluding the Relincho Project in Chile, were transferred to Lumina Copper; this included ownership of Minera Corriente Chile S.A. (Minera Corriente) which at the time indirectly held a 100% interest in the Taca Taca property as it was then structured. Effective August 19, 2012, Minera Corriente was wound up into Lumina Copper, leaving Lumina Copper the beneficial owner of all of the issued and outstanding shares of CASA.
Since completion of the Global Arrangement, CASA has subsequently acquired additional mineral concessions through a combination of purchases from third party owners, administrative lotteries, and staking. The present property position is shown in Figure 4-2 and concessions are listed in Table 4-1.
Some of the mining concessions that form the Grupo Minero and one ancillary mining concession are subject to a contractual royalty of 1.5% of net smelter returns (NSR) (Taca Taca Royalty). Franco Nevada Corp., through a wholly-owned subsidiary, holds the right to receive a 72% interest in the Taca Taca Royalty, and the remaining 28% interest is held by two individuals. A number of additional mining concessions are subject to contractual royalties of up to 1.5% of NSR. Table 4-1 includes a summary of the contractual royalties that apply with respect to the mining properties and rights comprising the Taca Taca property.
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A royalty of up to 3% net of smelting/refining, transportation, administrative, and plant processing costs (also known as the “mine mouth” value) is payable to the Province of Salta.
1.4 Property Description
The Project is located in a remote area of Argentina, as can be seen in Figure 1-1 and Figure 1-2. A network of paved and gravel roads from Salta to the towns of San Antonio de los Cobres and Tolar Grande provide access to the Project. The property is at an approximate elevation of 3,585 masl.
The Project is located within 10 km of the railway line that connects Salta with Antofagasta, Chile. The rail infrastructure is contemplated to be used to transport concentrates and select consumables to and from the Port of Mejillones, 65 km north of Antofagasta and other consumables from within Argentina.
Electrical power connection to the national power grid is available in the region at Olacapato to the north of the Project and a 345 kV transmission line over a length of 144 km is proposed to provide electrical power to the Project.
Although the region is arid, subsurface water is available in the local area. A water supply study and water balance analysis were completed for the Project and based on these studies, the processing water flow sheet shows that there are adequate sources of water available for the Project. Additional prospective areas have recently been identified near the Project that may be sources of additional fresh water.
Figure 1-2: Taca Taca Property
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1.5 Geology and Mineralization
The Taca Taca porphyry copper-gold-molybdenum deposit is hosted in the southern half of a 50 km long Ordovician batholith, which forms the Sierra de Taca Taca mountain range. The batholith consists of coarse-grained granite that is cut by several aplite dykes. This Early Paleozoic intrusion is intruded by Late Permian granites and aplites and overlain by Late Permian sediments and volcaniclastics. Narrow, north-south striking, steeply dipping rhyolitic dykes of Permo-Triassic age outcrop throughout the region. Oligocene rhyodacitic intrusions of the Santa Inés Formation are responsible for the porphyry copper mineralization and alteration at Taca Taca.
Late Tertiary red-bed sedimentary rocks are widely distributed in the region, but are most abundant east of Salar de Arizaro. These rocks possibly constitute the basal section of the sedimentary sequence that fills the salar basin. Lavas from recent (Pliocene to Pleistocene) volcanoes are exposed to the west and north of Taca Taca. Large evaporite deposits of alternating salts and sand were deposited in regional intermontane basins to form the present-day salars (Almandoz, 2008).
There are three main styles of mineralization associated with the Taca Taca copper-gold- molybdenum porphyry: supergene/hypogene porphyry copper mineralization, remnant oxide copper-gold mineralization in the leach cap, and hematite-quartz copper-gold veins. Each style of mineralization is discussed in more detail within Item 7.0.
1.6 Drilling
From 1975 through 2012, six different companies have completed seven drilling campaigns at the Project (Table 10-1). The drill collar locations are illustrated in Figure 10-1.
A total of 440 holes (163,537 m) have been drilled on the Taca Taca property. From 2010 to 2012, Lumina Copper drilled 273 holes (134,033 m). The mineral resource model is based on 310 drill holes (147,449 m) which tested the extent of the known porphyry mineralization.
1.7 Mineral Resource
The most recent mineral resource estimate for the Project (effective date of October 30, 2012) completed by SIM Geological Inc. (SIM Geological) and BD Resource Consulting, Inc. (BDRC), and the corresponding block model, has been used to develop the mine plan and production schedule for the PEA.
The majority of drill holes in the main deposit area are vertically oriented with holes spaced on a nominal 150 m grid pattern. At the northern end of the deposit, the final 500 m has been tested with holes that are consistently inclined -70° east.
The resource estimate was generated using drill hole sample assay results and an interpretation of the geologic model which relates to the spatial distribution of copper, gold, and molybdenum. Interpolation characteristics were defined based on the geology, drill hole spacing, and geostatistical analysis of the data. The resources were classified by their proximity to the sample locations and are reported, as required by NI 43-101, according to the CIM standards on Mineral Resources and Mineral Reserves (November 2010).
The Project's current mineral resource estimate (at a 0.3% copper equivalent cut-off grade) is shown in the table below:
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Table 1-1: Mineral Resource Summary
Size(1) Grade Contained Metal
Cu Eq(3) Cu Au Mo Cu Au Mo Tonnes (Million) (%) (%) (g/t) (%) (B lb) (M oz) (M lb)
Indicated Resources
2,165 0.57 0.44 0.08 0.013 21.15 5.56 615.8
Inferred Resources (2)
921 0.47 0.37 0.05 0.012 7.55 1.57 235.4 Notes: (1) Mineral resources have been estimated as at October 30, 2012. Totals may not add up due to rounding. (2) Inferred mineral resources have a great amount of uncertainty as to their existence and as to whether they can be mined legally or economically. It cannot be assumed that all or any part of inferred mineral resources will ever be upgraded to a higher category. (3) Copper equivalent (CuEq) calculated using $2.00/lb Cu, $800/oz Au, and $12.00/lb Mo and is not adjusted for mining and metallurgical recoveries as these remain uncertain. The formula used is as follows: CuEq = Cu% + (Au g/t x 0.583) + (Mo% x 6).
The Project's quality assurance/quality control (QA/QC) program was monitored by independent consultant Dr. Bruce M. Davis, FAusIMM of BDRC. Logging and sampling was completed at Lumina Copper’s secure facility located at the Project. Drill core was mechanically split on site before being sent to either ALS Chemex's or Alex Stewart Argentina's preparation facilities in Mendoza, Argentina.
Lumina Copper established a QA/QC protocol that comprised the use of reject duplicates, standards, and blanks inserted into the sample batches at regular intervals. Fine material duplicates were inserted during sample preparation (independent from the assay laboratory) by splitting of the pulps. A range of copper-gold-molybdenum standard reference materials (SRMs) of suitable matrix composition, together with blanks, was inserted by Lumina Copper during the core sampling procedure. The structure of this QA/QC program follows accepted industry standards. Irregular or suspect results were addressed in a timely manner in order to ensure the integrity of the database. The results of this QA/QC program indicate that the Project's database of sampling, analytical, and test data is of sufficient accuracy and precision to be used for the generation of mineral resource estimates.
The oxide gold mineral resource estimate defined within the Project's leached cap was treated as waste in the production schedule. Metallurgical test work completed to date on the oxide gold resource has been limited. Preliminary test results indicate, however, that future studies should be considered and performed in sufficient detail to support an economic analysis.
1.8 Mining
The Taca Taca deposit is amenable to conventional, large-scale, open pit mining methods. Floating cone (FC) evaluations were conducted to determine potentially economic pit limits and the mining phase (pushback) development sequence. Six mining phases were designed and used to estimate contained mineral resources, from which a mine production schedule was developed. This schedule was based on two grinding lines in the concentrator processing a total of 120,000 t/d for the first seven years of operation with the addition of a third grinding line in Year 8 increasing the daily mineralized material processing rate to 180,000 t/d.
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Wyllie & Norrish Rock Engineers Inc. (W&N), with sub consultants Fisher & Strickler Rock Engineering, LLC, (FSR) performed geotechnical analyses in support of scoping-level pit slope recommendations for the Taca Taca Project. These analyses were based primarily upon geotechnical data collected by W&N and Lumina Copper personnel during the course of exploration core drilling and dedicated geotechnical drilling in the years 2010 to 2012.
Six slope sectors were defined to control the floating cone projections and subsequent pushback designs. Overall slope angles for floating cones ranged from about 38° in the north walls, 42° in the east and southeast walls, to 44-46° in the southern walls, and about 42° in the northwestern quadrant of the pit.
Preproduction stripping is estimated at 251 Mt during a three-year development period. Sulfide milling operations are projected to last about 28 years.
Indicated sulphide resources of 1,545 Mt and grading 0.46% Cu and inferred sulphide resources of 106 Mt and grading 0.43% Cu, at an average stripping ratio of 1.57, were estimated in this production schedule using a declining cut-off grade strategy that increases the potential present value.
This 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. There is no certainty that the results of this PEA will be realized. Mineral resources that are not mineral reserves have no demonstrated economic viability.
Workforce and equipment requirements were estimated on the basis of working two 12-hour shifts per day, 7 d/wk, 360 d/y (allotting five days for weather and holiday-related interruptions). A four- rotating-crew work schedule will be required for continuous operator and maintenance coverage. A peak mine workforce of 874 is projected in Year 7.
Large-scale equipment was selected for maximum economies of scale. Taca Taca mining would be conducted from 15 m high benches using conventional shovel-truck practices. Electric drills and shovels were chosen because of their lower operating costs and better reliability. The rest of the mining fleet would consist of diesel-powered machinery that provides flexibility in pit operations.
The selected primary mining fleet includes the following equipment:
Rotary blasthole drills capable of 270 to 311 mm-diameter holes 60 m3 rope shovels 42 m3 hydraulic shovel 40 m3 front-end loader (FEL) 363 t off-highway haul trucks 635 kW and 435 kW crawler dozers 600 kW rubber-tired dozer 370 kW rubber-tired dozers 400 kW and 220 kW motor graders 120,000 l (134 t) water trucks
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1.9 Mineral Reserve Estimate
This item is not applicable to this PEA.
1.10 Metallurgical Testing
Laboratorio Plenge (Plenge) of Lima, Peru conducted a series of test programs on Taca Taca samples over a period of three years starting in April 2010. The final test program was completed in October 2012. Programs consisted of:
Scoping level comminution and flotation tests; Variability and optimization flotation tests, including copper/molybdenum separation; and, Settling and filtration tests.
Plenge’s final test program was completed on representative core samples selected from across the deposit on the basis of spatial, physical, mineralogical, and chemical characteristics. For the majority of the test work that forms the basis of the PEA, core was divided into four composite samples, two for each major alteration type, supergene and primary.
The two composites for each alteration type represented two different periods in the anticipated mine production schedule, Years 1-5 and Years 6-10.
Observations are summarized below:
Ausenco reviewed the test work and concluded it is reasonably extensive and suitable for this level of study. The comminution data are considered adequate for a conceptual milling circuit design. The Taca Taca mineralized material is of moderate competency and hardness, and amenable to grinding in a conventional SAG-ball milling circuit with pebble crushing (SABC) and re-grinding. The location of the samples and drill holes are reasonably representative of the deposit for a PEA given the nature and continuity of rock types and mineralization of the deposit. Recoveries over the life of mine (LOM) are expected to range from 88% to 92% for copper, 56% to 57% for molybdenum, and 61% to 65% for gold, which will be contained in the copper concentrate. LOM metal recoveries are expected to average approximately 90% for copper, 64% for gold, and 57% for molybdenum.
1.11 Process Design and Recovery
The Taca Taca concentrator is planned to process 120,000 t/d of run of mine (ROM) material. Copper and molybdenum concentrates and tailings will be produced. The proposed process includes crushing and grinding of the ROM material, bulk copper-molybdenum rougher and cleaner flotation, regrinding, copper-molybdenum separation, molybdenum flotation, and dewatering of copper and molybdenum concentrates. The flotation tailings will be thickened before placement in a tailings storage facility (TSF). Prior to Year 8 an expansion is planned to be undertaken to increase the capacity of the concentrator to 180,000 t/d with the addition of a third milling and bulk rougher flotation line.
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The copper and molybdenum concentrates are planned to be transported by truck from the concentrator to the rail load-out facility where they will be transported by rail across the Argentinian- Chilean border to the Port of Mejillones, Chile for shipment to international customers.
1.12 Execution Plan and Schedule
An execution schedule has been developed to advance the Project if Feasibility Study results are positive and a development decision is made. The overall preproduction period of 48 months is driven by the need to construct the site infrastructure primarily required to support preproduction stripping. Two years have been estimated for construction of the processing facilities and related infrastructure. The preproduction period ends with the commissioning of the first grinding line (one SAG mill and two ball mills) and its associated flotation circuit. Commissioning of the second grinding line would follow three months later, the staggered start allowing for normal production ramp-up activities. A third line would be constructed in the sixth and seventh years of operation and commissioned in the eighth year, bringing total production to 180,000 t/d.
1.13 Capital Cost
Capital cost estimates for the Technical Report have been completed. Approximately 251 Mt of preproduction stripping, including stockpiling, will be required prior to mining operations commencing. It has been estimated that it will take approximately 2.5 years to complete preproduction stripping at a capitalized cost of $416.1 million. The cost of preproduction stripping, including removal of the leach cap, has been included in the initial capital cost estimate. The total initial capital cost including the mine, concentrator, and infrastructure is estimated to be approximately $3.0 billion including a total of 15% contingency based on total direct and indirect costs. The following table summarizes the capital cost estimate:
Table 1-2: Capital Cost Summary
Description Estimate ($US M) Mine $581.5 Preproduction stripping $416.1 Plant and Processing $685.5 Infrastructure $215.3 Tailings Storage and Waste Rock Storage $139.5 Other $581.0 Contingency $386.5 Total Initial Capital Costs $3,005.5 Start-up Working Capital $54.9 Capital costs for 3rd mill and flotation line and $431.2 associated ancillary costs LOM Sustaining Capital Costs $1,375.5
Note: Figures above may not add up due to rounding.
The capital cost estimates have been compiled with an accuracy level of -25% to +35%.
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The initial capital cost estimate for this Technical Report compares favourably to the initial capital costs cited for comparable copper projects under development. The capital intensity ratio on initial capital (initial capital divided by average annual copper production) is a measure of the amount of investment in initial capital infrastructure required to produce a tonne of copper at a project. The capital intensity ratio on initial capital is estimated to be $11,090/t of copper production (for production prior to the expansion in Year 8). The term "capital intensity ratio" does not have a standard meaning and may not be directly comparable to capital intensity ratios presented by other issuers.
The Qualified Person for this section has reviewed and approved the capital cost estimates for inclusion in this Technical Report.
Capital costs are discussed in more detail in Item 21.0.
This 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. These is no certainty that the results of this PEA will be realized. Mineral resources that are not mineral reserves have no demonstrated economic viability.
1.14 Operating Cost
The PEA estimates that the C-1 cash costs (net of by-product credits) over the LOM will average $1.11/lb copper sold. C-1 cash costs include at-mine cash operating costs, treatment and refining charges, royalties, mine reclamation and closure costs, and copper and molybdenum concentrate transportation, and freight costs.
The following LOM operating costs have been forecast for the Project:
Table 1-3: Operating Cost Summary
Site Operating Costs US $/t mill feed Mining $4.67 Processing $4.26 Infrastructure Maintenance $0.06 Railroad Operations $0.19 General & Administration $0.57 Mine Closure Costs $0.02 Total Site Operating Costs $9.77 Other Key Costs $70/dry metric tonnes (dmt) Cu Copper Concentrate Treatment Charges concentrate Copper Refining Charges $0.07/lb Cu $79.67/wet metric tonnes (wmt) Ocean Freight, Port Handling & Other Costs Cu concentrate
Methodologies and further details are presented in Item 21.0.
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1.15 Marketing Studies
H&H Metals Corp. (H&H) of New York completed a marketing study for the Project. Using contacts with smelters and recent data from other projects, H&H completed the following marketing aspects in its report: supply and demand for both copper and molybdenum concentrates, including anticipated production from new projects in the construction or planning stages; smelter capacities, utilization, and the impacts on treatment charges (TCs), refining charges (RCs), and payfors; ocean freight costs; and future metals pricing. Details are provided below.
Supply and Demand
While supply and demand dictates pricing for many items, it is only one consideration for metals such as copper and molybdenum. Speculation by investors complicates market analysis. Less than transparent data by China regarding production and inventories further complicates analysis of supply and demand, as does the impact of worldwide economic conditions.
The trend to more affluent populations on the whole, as well as sustained population growth in the populous countries of China and India, support steady growth in demand for copper, in particular, for housing and other infrastructure.
In the short term, existing inventories are expected to be drawn down as new projects and expansions of existing operations are planned for completion. Both of these factors are expected to place downward pressure on copper pricing until later in the decade. At that point, the steadily increasing demand mentioned above is expected to overtake and surpass the increases in supply.
Uncertainty in the supply and demand scenario summarized above is introduced by: new or expanded production facilities coming online later than originally planned; cancellation of new or expanded production facilities due to market, general economic, or company financial conditions; or management of the market sector by the government in a large consumer/producer such as China.
Smelter Capacities and Utilization
For the most part, smelter capacity is fixed. The relationship between capacity and utilization dictates a smelter’s profitability, hence its setting of TCs, RCs, and payfors. There is significant variability of utilization among smelters across the industry, hence considerable variability of TCs, RCs, and payfors. In order to obtain more concentrates, some smelters are agreeing to lower charges.
In the long term, TCs and RCs are expected to increase for smelters to better cover their costs. However, it is worth noting that Lumina Copper may expect to receive premium terms for its clean concentrate. According to H&H, a number of smelters need clean concentrates to blend with their substantial supplies and inventories of dirty concentrates.
H&H’s forecasts for TCs, RCs, and payfors were utilized in the Project cash flow, as detailed in Table 22-4.
Ocean Freight
During the minerals boom period, shipping companies aggressively built vessels to transport the mineral products from producers to markets. Currently, the availability of vessels significantly exceeds the need. Many vessels remain idle with financial building costs exceeding their current value.
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Opportunities for reasonable freight costs are available, particularly with negotiation of long-term freight contracts. H&H’s forecast for freight cost of $53 wmt for shipment to Asia has been incorporated in the Project cash flow.
Future Metals Pricing
After analysis and discussion, H&H forecast the following metal prices for the Project shown below in Table 1-4.
Table 1-4: Metal Price Forecast
Product Range Recommend Price
Copper $2.90 - $4.10 $3.10
Molybdenum $11.00 - $15.00 $13.00
Gold $1,350 - $1,900 $1,650
Silver $26.00 - $38.00 $35.00
In addition to the H&H forecast, consideration was given to a $2.89/lb consensus long-term price forecast made by 21 financial institutions (Thomson One Analytics, March 2013). The PEA economic analysis utilizes the following more conservative pricing forecast (Table 1-5), which has been applied throughout the projected 28 year mine life of the Project.
Table 1-5: Project Metals Pricing
Product Price
Copper $2.75/lb
Molybdenum $12.00/lb
Gold $1,200/Toz
1.16 Economic Evaluation
Inputs for the economic model are listed below for easy reference, again as Table 22-1, and discussed in detail in Item 22.0.
Table 1-6: Economic Model Inputs
Description Values
Construction Period 30 months Preproduction Period 4 years LOM after Preproduction 28 years LOM Sulfide Mill Feed (Kt) 1,650,792 LOM Copper Concentrate (DMT) 21,615,739 LOM Molybdenum Concentrate (DMT) 227,884
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Description Values
Market Price Copper Price (LOM $/lb Cu) 2.75 Gold Price (LOM $/oz Au) 1,200.00 Molybdenum Price (LOM $/lb Mo) 12.00 Cost and Tax Criteria Estimate Basis 1st Qtr 2013 USD Inflation/Currency Fluctuation None Leverage 100% Equity Income Tax - Argentina 35% Argentine Retention Tax 10% Less: Puna Investment Credit -2.5% Net Retention Tax 7.5% (on Gross Revenue less: TCs, RCs, port handling, ocean freight, and
75% of rail use fees and railroad operation costs to be incurred in Chile)
Depreciation - Argentina Section 13 Infrastructure Construction & Equipment 60/20/20 Machinery, Equipment, and Vehicles 1/3 for 3 years IVA - Value Added Tax (VAT) Payment/Recovery Excluded Royalties Salta Provincial Minemouth Royalty 3.0% (on Gross Revenue less: TCs, RCs, freight, processing, infrastructure maintenance, railroad operation, and general & administration costs) Third Party Royalty on Modified NSR 1.5% (on Gross Revenue less: TCs, RCs, freight, railroad operation, Provincial Minemouth Royalty, and Net Retention Tax paid) Concentrate (Con) Transportation Charges Cu Con: Rail Use Fees, Port Handling, and Ocean Shipping ($/WMT) 79.67 Mo Con: Rail Use Fees and Port Handling ($/WMT) 15.67 Assuming containerization of Mo con product and considered delivered
at port. Payment Terms Cu Con: Cash Against Documents (CAD) one week after shipping 90% Balance received eight weeks after shipping 10% Mo Con: Cash Against Documents (CAD) week of arrival at port 90% Balance received four weeks after delivery to port 10%
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This PEA is preliminary in nature and includes inferred mineral resources that are considered too speculative geologically to have the economic considerations applied to them that would enable them to be categorized as mineral reserves. There is no certainty that the results of this PEA will be realized. Mineral resources that are not mineral reserves have no demonstrated economic viability.
The cash flow forecast by the PEA estimates payback of initial capital investment to occur approximately 3.8 years after start of production. The Project is estimated to have an after tax internal rate of return (IRR) of 17.2%.
The following table shows the estimated after tax net present value (NPV) for the Project’s cash flows at various discount rates.
Table 1-7: Net Present Value with Mid-Period Adjustment
Discount Rate 4% 6% 8% 10% 12%
NPV ($M) $4,610.1 $3,121.5 $2,087.3 $1,352.6 $820.5
The following figures show the sensitivity of the estimated after tax IRR and NPV (8% discount rate) to changes in metal prices.
Figure 1-3: IRR Sensitivity Analysis – Metal Prices
Figure 1-4: NPV Sensitivity Analysis – Metal Prices
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1.17 Interpretations and Conclusions
Interpretations and conclusions of the Qualified Persons of the Taca Taca PEA are listed below:
The results of the PEA indicate that the Project is a robust project at this stage of development demonstrating favourable economic potential that warrants further work toward the next stage of development, prefeasibility. The exploration program continues to demonstrate the potential for future growth of the resource. The sample preparation, security, and procedures followed by Lumina Copper are adequate to support a mineral resource estimate. Assay data provided by Lumina Copper were represented accurately and suitable for use in resource estimation. There are no environmental issues existing or anticipated that could materially impact the ability to develop the Taca Taca mine. There are no known factors related to metallurgical, environmental, permitting, legal, title, taxation, socio-economic, marketing, or political issues which could materially affect the mineral resource estimates. Safety factors and probabilities of failure (pf) estimated for the final pit slopes at Taca Taca are well within acceptable limits as defined by the state-of-practice rock mass strength considerations. The recommended overall pit slope templates are more conservative by rock mass strength because the designs are based on bench configurations controlled by structural fabric. Consequently, there is a future opportunity to optimize overall slopes by incorporating controlled blasting and/or single benching to steepen bench face angles as well as an opportunity to lessen the degree of pit slope depressurization. The metallurgical test work undertaken is reasonably extensive and suitable for this level of study. The comminution data are considered adequate for a conceptual milling circuit design. The design of the processing circuits is based on this test work data in conjunction with assumptions based on typical industry values. The Taca Taca mineralized material is of moderate competency and hardness, and amenable to grinding in a conventional SABC. The mineralogy is fine grained and test work indicates a requirement to re-grind to a fine particle size to achieve adequate liberation for flotation as is common within the industry. Recoveries over the LOM are expected to range from 88% to 92% for copper, 56% to 57% for molybdenum, and 61% to 65% for gold, which will be contained in the copper concentrate. LOM metal recoveries are expected to average approximately 90% for copper, 64% for gold, and 57% for molybdenum. The cost to construct a 144 km transmission line has been included in the initial capital cost estimate. This power line will connect the Project to a 1,000 MW capacity line that was previously used to export power from the TermoAndes S.A. power plant located near the city of Salta. The Salta power plant is comprised of two 365 MW gas fired generating units that use gas sourced from the gas fields located in northern Salta Province. The plant currently has approximately 200 MW of excess generating capacity that is considered to be sufficient for the Project’s power requirements as defined in this PEA.
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The railway line connecting Antofagasta and the city of Salta is located approximately 10 km from the Project. The railway line has the capacity to handle the transportation of all of the concentrates produced at the Project. The construction of a load-out facility and rail spur near the concentrator has been included as part of the capital cost estimate. It has been assumed that the Project will operate its own fleet of locomotives and rolling stock, which have also been included in the Project costs, to transport the concentrates and consumables between the Project and the Port of Mejillones, 65 km to the north of Antofagasta. A water supply and water balance analysis were completed for the Project. This analysis, supported by metallurgical test work using water with varying salinity levels, derived a processing make-up water flow sheet comprising a combination of high salinity water from the neighbouring salar, fresh water derived from wells, and desalinated brackish well water. Conceptual design, capital and operating costs for the construction and operation of a water treatment plant were completed for the PEA. Based on the current studies, the processing water flow sheet shows that there are adequate sources of water available for the Project. Additional prospective areas have recently been identified near the Project that may be sources of additional fresh water, which could further optimize the process water flow sheet. The Project has been designed to meet World Bank Guidelines for social and environmental management practices. Baseline studies completed to date have included surface and groundwater quality, acid rock drainage, meteorological, and social. Provisions have been made within the mine plan and operating costs to account for the environmental protection and rehabilitation of the site once mining has been completed to meet the World Bank Guidelines. 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 characterized as mineral reserves. There is no certainty that these inferred resources will ever be upgraded or that the results stated in this PEA will be realized. Mineral resources that are not mineral reserves have no demonstrated economic viability.
1.18 Recommendations
Based on the results of the PEA, the Qualified Persons recommend that Lumina Copper complete a Prefeasibility Study (PFS) to further define the Project in order to assess its technical and economic viability and to support permitting activities.
General tasks and estimated costs to complete the PFS are summarized below in Table 1-8.
Table 1-8: Estimated Cost for Recommended Future Work
Estimated Cost Task (US$000)
1. Explore potential extensions of pit mineralization, including 10,000 m of DD drilling at approximately 10 locations, and necessary geologic, $5,000 logistical, assaying, and administrative support ($500/m allowance; 21% IVA included).
2. Update resource model/estimate with additional exploration drilling $50 results, including QA/QC.
Subtotal Exploration and Resource Estimate $5,050
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Estimated Cost Task (US$000)
3. Complete Prefeasibility Study a) Complete condemnation drilling for facility siting, including 5,000 $2,500 m of drilling ($500/m allowance; 21% IVA included). b) Additional mine geotechnical data collection and engineering analysis, including 4,200 m of DD drilling at 5-7 locations ($500/m $2,700 allowance; 21% IVA included). c) Revise mine design and production schedule based on updated resource model; upgrade accuracy of mining capital, operating, $150 and sustaining capital cost estimates to PFS level. d) Complete additional hydrogeological field investigations, engineering analysis, and computer modeling in support of mine $1,500 dewatering and project water supply. e) Complete further evaluation of new water feed to the water treatment plant and upgrade capital and operating costs to PFS $15 level. f) Conduct additional metallurgical test work, primarily consisting of spatial, grade, and mineralogic variability testing of representative $750 samples from across the deposit, in numbers accepted by the industry as being statistically representative. g) Complete process and infrastructure design and associated costs $1,200 to a PFS level. h) Complete field geotechnical and laboratory investigations; complete PFS level design and associated costs for geotechnical $725 infrastructure (TSF, WRSF, and roads). i) Perform environmental baseline studies and permitting activities. $250
j) Complete an updated marketing study. $50
k) Complete an updated power supply study. $50 l) Update and upgrade logistics and transportation study to PFS $100 level. m) Perform study management and coordination, execution planning and scheduling, Owner’s cost estimating, and economic $450 evaluation. Subtotal PFS Estimate $10,440 Total Estimated Cost for Recommended Future Work $15,490
1.19 Cautionary Note Regarding Forward-Looking Information and Statements
Information and statements contained in this Technical Report that are not historical facts are “forward-looking information” or “forward-looking statements” within the meaning of applicable Canadian securities legislation and the United States Private Securities Litigation Reform Act of 1995, respectively, and involve risks and uncertainties. Examples of forward-looking information and statements contained in this Technical Report include information and statements with respect to:
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Lumina Copper’s plans and expectations for the Project; the results of the economic analysis of Lumina Copper’s Taca Taca, including, but not limited to, base case parameters and assumptions, base case analysis, forecasts of net present value, internal rate of return, initial and sustaining capital costs, operating costs and cash flows and sensitivity analyses, taxes and royalties; Lumina Copper’s plans related to mine and concentrator development and design, operations, equipment, and infrastructure; Lumina Copper’s proposed throughput, production schedule, LOM estimates, and preproduction stripping requirements; Capital intensity on initial capital estimates and underlying capital cost and production forecasts; metal price projections; Lumina Copper’s plans related to mineral processing and recovery methods; mineral resource estimates and assumptions; the potential of Lumina Copper to extend areas of known mineralization; estimates of long term power, transportation, and labor costs, water requirements and waste to mineralized material stripping ratios; estimates of mine reclamation and closure costs; the results and further testing of Lumina Copper’s metallurgical testing programs including, but not limited to estimates of metal recovery rates; Lumina Copper’s plans relating to exploration and development of the project, including permitting and regulatory requirements related to any such plans; Lumina Copper’s plans and projected costs to complete additional drilling and a PFS; Lumina Copper’s plans to meet World Bank’s Group Policy and Performance Standards and Equator Principles regarding social and environmental sustainability; Lumina Copper’s plans to address environmental compliance, reclamation, and liabilities; potential to optimize the process water flow sheet; risks related to performance of the Project and opportunities to improve Project performance; and, potential opportunities identified in Section 25.22.
In certain cases, forward looking information can be identified by the use of words such as “plans”, “expects”, “is expected”, “budgets”, “forecasts”, “anticipates”, “estimates”, “intends”, “targets”, “scheduled”, “believes”, “appears”, “likely”, “typically”, “potential”, “continue”, “strategy”, or “proposed”, or variations (including negative variations) of such words and phrases or may be identified by statements to the effect that certain actions, events or results, “may”, “could”, “should”, “would”, “will be” or “shall” be taken, occur or be achieved.
Various assumptions or factors are typically applied in drawing conclusions or making the forecasts or projections set out in forward-looking information and statements. In some instances, material assumptions and factors are presented or discussed elsewhere in this Technical Report in connection with the statements or disclosure containing the forward-looking information and
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statements. You are cautioned that the following list of material factors and assumptions is not exhaustive. The factors and assumptions include, but are not limited to, assumptions concerning metals prices; cut-off grades; short and long term power prices; transportation, water, and labour requirements; processing recovery rates; mine plans and production scheduling; process and infrastructure design and implementation; accuracy of the estimation of operating and capital costs; applicable tax and royalty rates; open-pit design; accuracy of mineral resource estimates and resource modeling; reliability of sampling and assay data; representativeness of mineralization; accuracy of metallurgical test work; and timely receipt of regulatory approvals.
Forward-looking statements are subject to a variety of known and unknown risks, uncertainties and other factors which could cause actual events or results to differ materially from those expressed or implied by the forward-looking statements, including, without limitation:
risks relating to copper and other mineral price fluctuations;
risks relating to estimates of mineral resources, production, purchases, capital and operating costs, decommissioning or reclamation expenses, proving to be inaccurate;
the inherent operational risks associated with mining and mineral exploration activities, many of which are beyond Lumina Copper’s control, including competition, accidents, and labour disputes;
risks relating to Lumina Copper’s ability to enforce Lumina Copper’s legal rights under permits or licenses or risk that Lumina Copper will become subject to litigation or arbitration that has an adverse outcome;
risks relating to Lumina Copper’s project being in Argentina, including political, economic and regulatory instability, expropriation, and financing risk;
risks related to restrictions on import of mining and plant equipment, supplies, and reagents;
risks relating to potential challenges to Lumina Copper’s right to explore and/or develop the Project, including title disputes or claims;
risks relating to mineral resource estimates being based on interpretations and assumptions which may result in less mineral production under actual circumstances;
risks relating to Lumina Copper’s operations being subject to environmental compliance and remediation requirements, which may increase the cost of doing business and restrict Lumina Copper’s operations;
risks relating to being adversely affected by environmental, safety and regulatory risks, including increased regulatory burdens or delays and changes of law;
risks relating to inadequate insurance or inability to obtain insurance;
risks relating to the fact that Lumina Copper’s properties are not yet in commercial production;
risks related to the failure of plant equipment or processes to operate as anticipated;
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risks relating to the uncertainty as to whether Lumina Copper will acquire permitting required to further explore and develop the Project and risks related to the permitting timelines;
risks related to changes in Project parameters as plans continue to be refined;
risks relating to fluctuations in foreign currency exchange rates, interest rates and tax rates;
risks relating to Lumina Copper’s ability to raise funding to continue its exploration, development and mining activities; and,
risks identified in Section 25.2.1 of this Technical Report.
This list is not exhaustive of the factors that may affect the forward-looking information and statements contained in this Technical Report. Should one or more of these risks and uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those described in the forward-looking information and statements. The forward-looking information and statements contained in this Technical Report are based on beliefs, expectations and opinions as of the effective date of this Technical Report. For the reasons set forth above, readers are cautioned not to place undue reliance on forward-looking information. Lumina Copper and the Qualified Persons of this Technical Report do not undertake to update any forward-looking information and statements included herein, except in accordance with applicable securities laws.
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2 Introduction
2.1 Purpose of the Technical Report
The Taca Taca porphyry copper-gold-molybdenum deposit located in northwestern Argentina in the Puna (Altiplano) region of Salta Province is beneficially owned by Lumina Copper, based in Vancouver, British Columbia, Canada. This Technical Report has been prepared for Lumina Copper by or under the supervision of Qualified Persons within the meaning of NI 43-101 in support of Lumina Copper’s disclosure of scientific and technical information for the Project.
This Technical Report supersedes and provides an update of the Technical Report prepared for Lumina Copper entitled “Taca Taca Property Porphyry Copper – Gold – Molybdenum Project, Argentina, NI 43-101 Technical Report”, dated January 4, 2013, with an effective date of October 30, 2012.
The PEA defines the current overall scope of the Project and provides the information required by Lumina Copper to make decisions regarding further evaluation and development of mining, processing, and infrastructure facilities and provides the basis for the estimates, assumptions, parameters, designs, and criteria included in this Technical Report.
MTB Project Management Professionals, Inc. (MTB), a project management consulting firm, assisted Ausenco in completing this Technical Report under the supervision of the Qualified Persons listed below, and under the overall supervision of Kevin Scott, P.Eng.
2.2 Sources of Information
This Technical Report is based on data supplied by Lumina Copper. The information presented, opinions, and conclusions stated, and estimates made are based on the following information:
Source documents used for this Technical Report are summarized in Item 27.0 of this Technical Report; Assumptions, conditions, and qualifications as set forth in the Technical Report. This report is based on drilling and sampling data available as of October 30, 2012. The resource model, including subsequent data validation and review, was completed in November 2012 and released on November 21, 2012 in a press release by Lumina Copper; Data, reports, and opinions from prior owners and third-party entities; and Personal inspection and review.
The below-listed Qualified Persons are responsible for the information provided in the indicated items.
William L. Rose, P.E., of WLR Consulting, Inc. (WLRC), is responsible for the information provided in Items 15 and 16 and portions of 1, 2, 21, 22, 25, 26 and 27.
Robert Sim, P. Geo., of SIM Geological, is responsible for the information provided in Item 14, and portions of 1, 7, 8, 9, 10, 25, 26, and 27.
Bruce Davis, Ph.D., FAusIMM, of BDRC, is responsible for the information provided in Items 11, 12, and portions of 1, 7, 8, 9, 10, 14, 25, 26, and 27.
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Kevin Scott, P. Eng., of Ausenco, is responsible for the information provided in Items 1, 2, 3, 4, 5, 6, 13, 17, 18, 19, 22, 23, 24, and portions of 21, 25, 26, and 27.
Scott C. Elfen, P. E., of Ausenco, is responsible for the information provided in Item 20 and portions of Items 1, 4, 17, 18, 21, 25, and 26.
2.3 Personal Inspection of the Taca Taca Project
The below-listed Qualified Persons conducted personal inspections of the Project as indicated:
Kevin Scott conducted a site visit on October 23-24, 2012 for the purposes of understanding the local conditions as they relate to process plant and infrastructure development activities and to verify other information required for the Technical Report.
William Rose completed a site visit January 21-22, 2011. The purpose of the site visit was to review progress and area geology, view core samples, observe drill sites, and inspect topography.
Robert Sim visited the site from July 1-3, 2008 and again from June 21-23, 2012; he reviewed drilling activities, inspected core from numerous drill holes, reviewed sampling procedures, and visited a series of drill sites on the property. On June 23, 2012, Robert Sim also visited Lumina Copper’s core facility and offices in Salta where he examined core from recent drilling and reviewed Lumina Copper’s sampling procedures.
Bruce Davis visited the site from January 20-22, 2011 and again from June 21-23, 2012; he reviewed Lumina Copper’s sampling procedures, inspected core from select drill holes, and visited select drill sites. On June 23, 2012, Bruce Davis also visited Lumina Copper’s core facility and offices in Salta where he examined core from recent drilling and reviewed Lumina Copper’s sampling procedures.
Scott Elfen completed a site visit January 21-22, 2011. The purpose of the site visit was to gain an understanding of the local conditions as they relate to Project infrastructure development activities and Project environmental and social concerns.
2.4 Currency Assumptions
All measurement units used in this report are metric, and currency is expressed in US dollars ($) unless stated otherwise. The currency used in Argentina is the peso (ARS $): the official exchange rate at the effective date of this Technical Report was approximately 5.04 ARS $ per $1.
The effective date for this Technical Report and the mineral resource estimate is April 9, 2013.
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3 Reliance on Other Experts
The Qualified Persons have not independently conducted any title or related searches, but have relied upon a legal title opinion to Lumina Copper from Zaballa-Carchio Abogados based in Buenos Aires, Argentina, dated May 2, 2013 concerning the ownership and title to the Project (described in Items 1.3 and 4.2). The Qualified Persons believe this data and information are essentially complete and correct to the best of their knowledge and that no information was intentionally withheld that would affect the conclusions made herein. The authors have not researched the property title or mineral rights for the Project and express no legal opinion as to the ownership status of the property.
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4 Property Description and Location
4.1 Property Location
The Taca Taca property is located in the Puna (Altiplano) region of Salta Province, northwest Argentina at an approximate elevation of 3,585 masl. It is approximately 230 km west of the city of Salta and 55 km east of the Chilean border (Figure 4-1). The center of the property is at latitude 24.7oS and longitude 68.0oW. The UTM coordinates are 7283500 N and 2628000 E (geographic projection: Gauss-Kruger POSGAR 94/Argentina WGS84, Zone 2).
Figure 4-1: Property Location Map (Afrainlle, June 2012)
4.2 Property Ownership and Agreements
The Project consists of the Grupo Minero Taca Taca concession (Grupo Minero) that covers 2,559.96 ha, and 27 additional mining (mina) and exploration (cateo) concessions and one land use application, owned wholly or in part, that covers 58,001.32 ha. In the region, one land use application, one additional mining concession application, and two additional exploration concession applications have been registered, but not yet granted; these total 3,291.95 ha. The mining properties and rights comprising the Taca Taca property, including the applicable file
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numbers, area, status, and contractual royalty encumbrances are listed in Table 4-1 and the present property position is shown in Figure 4-2.
Table 4-1: Mining Concessions
Contractual Concession File Number Area (ha) Status Royalty Mina Fruso Corriente Claim 18.646/2007 4,502.57** Granted property Pending Mina Fruso Corriente Sur Claim 21.956 1,002.57** application Mina Corriente IV Claim 19.716/2009 3,493.84 Granted property Mina Fruso Corriente II Claim 18.685/2007 2,504.00 Granted property Mina Corriente III Claim 19.715/2009 2,426.63 Granted property Mina Amira Norte Claim 18.832/2007 1,500.15 Granted property 1.5% NSR Granted property 0.75% NSR Mina Francisco 1 Claim 18.048/2005 1,313.49 (50%) Granted property 0.75% NSR Mina Francisco 2 Claim 18.049 1,000.22 (50%) Mina Corriente V Claim 20.821/2011 522.96 Granted property Mina Amira Claim 18.794/2007 434.16 Granted property 1.5% NSR Mina Taca Taca 9 Claim 15.949/1997 376.46 Granted property 1.5% NSR Mina La Sarita Claim 1434/1942 167.99 Granted property Mina Corriente I Claim 19.694/2009 134.44 Granted property Mina Amira Este Claim 19.249/2008 81.05 Granted property 1.5% NSR Mina Corriente II Claim 19.693/2009 71.88 Granted property Mina Federico Claim 9078/1974 39.98 Granted property Mina Don Ramón Claim 18.851/2007 26.51 Granted property Grupo Minero Taca Taca Claim 18.690 2,559.96 Granted property 1.5% NSR* • Mina Carla Claim 14.460 Granted property •Mina Paula Claim 14.461 Granted property •Mina Punilla V Claim 15.478 Granted property •Mina Tacalto 6 Claim 15.727 Granted property •Mina Tacalto 8 Claim 15.834 Granted property •Mina Taca Taca 1 Claim 7.578 Granted property •Mina Taca Taca 2 Claim 7.579 Granted property •Mina Taca Taca 3 Claim 7.580 Granted property •Mina Taca Taca 4 Claim 7.581 Granted property •Mina Taca Taca 5 Claim 7.582 Granted property •Mina Taca Taca 6 Claim 7.583 Granted property •Mina Taca Taca 7 Claim 7.584 Granted property •Mina Taca Taca 8 Claim 15.948 Granted property Cateo Claim 21.227/2011 8,924.29 Granted property Cateo Claim 21.226/2011 7,752.04 Granted property
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Contractual Concession File Number Area (ha) Status Royalty Cateo Claim 21.225/2011 6,262.51 Granted property Cateo "Aracar" Claim 21.386 927.75 Granted property Mina “ La Escondida” Claim 17.642 37.00 Granted property Mina “La Escondidita” Claim 17.879 6.00 Granted property Mina La Gloria Claim 21.307 196.88 Granted property 1.5% NSR Granted –held in Mina Don Francisco Claim 18.034 trust for CASA by 340.04 S. Arbeleche Pending Land Use application Claim 21.679 90.46 application
Cateo Claim 21.705 4,760.00 Granted property Cateo Claim 21.709 5,599.00 Granted property Pending Cateo "Chuculaqui" Claim 21.387 3,154.12 application Cateo " EX3" Claim 21.390 4,599.48 Granted property Pending Johncito Claim 21.498 47.37 application Granted properties total (ha) 60,561.28 Pending applications total (ha) 3,291.95
Grand total (ha) 63,853.23
* A 1.5% NSR is payable in respect of each of the concessions formerly comprising the area covered by the Grupo Minero, other than Mina Punilla V, Mina Tacalto 6, and Mina Tacalto 8. **Mina Fruso Corriente will be reduced to 3,500 ha as soon as the pending application for Mina Fruso Corriente Sur is granted. The 1,002.57 hectares to be transferred from Mina Fruso Corriente to Mina Fruso Corriente Sur are currently granted under Mina Fruso Corriente concession; only the transfer is pending.
A royalty of up to 3% net of smelting/refining, transportation, administrative, and plant processing costs (also known as the “mine mouth” value) is payable to the Province of Salta.
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Figure 4-2: Claim Map
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The Grupo Minero concessions are maintained through annual fees (canon) which at current official exchange rates are equivalent to $4,410 per year. The remaining concessions have an annual canon fee of $23,360. One-half of the total annual canon fees ($13,885) are paid semi-annually in June and December.
As of May 2, 2013, all of the mining and exploration concessions were in good standing and canon fees have been paid through June 30, 2013. The Grupo Minero and other concessions are valid for an unlimited period of time as long as the semi-annual canon payments are made. All exploration concessions will have to be converted to mine properties in 2013 and 2014. The Grupo Minero and mining concessions include the right to exploit, subject to being granted by an environmental permit for exploitation. The exploration concessions include the right to explore for all metals or minerals.
The surface lands covering the Taca Taca property are owned by the Province of Salta and the necessary access permits were granted for the current drilling work. All known mineralized zones are located hundreds of metres within the limits of the Taca Taca property.
The Grupo Minero and other mining and exploration concessions are registered under the name Corriente Argentina S.A. (CASA) except for Mina Don Francisco which is held in trust for CASA by S. Arbeleche and Mina Francisco 1 and Mina Francisco 2 which are jointly owned through a company 50% owned by CASA and 50% owned by Salta Exploraciones S.A. (SESA). Lumina Copper is the beneficial owner of all of the issued and outstanding shares of CASA. A member of Lumina Copper management holds approximately 1.0% of the issued and outstanding shares in the capital of CASA in trust for the benefit of Lumina Copper in order to address certain requirements applicable to Argentinian companies under Argentine corporate law.
Lumina Copper first acquired an interest in the Taca Taca property when shareholders of Global Copper Corp. (Global Copper) approved a corporate reorganization effective August 1, 2008 by way of a statutory plan of arrangement (Global Arrangement); pursuant to the Global Arrangement, Teck Resources acquired all Global Copper’s shares. Global Copper’s assets, excluding the Relincho Project in Chile, were transferred to Lumina Copper; this included ownership of Minera Corriente which at the time indirectly held a 100% interest in the Taca Taca property as it was then structured. Effective August 19, 2012, Minera Corriente Chile S.A. (Minera Corriente) was wound up into Lumina Copper, leaving Lumina Copper the beneficial owner of all of the issued and outstanding shares of CASA.
Since completion of the Global Arrangement, CASA has subsequently acquired additional mineral concessions through a combination of purchases from third party owners, lotteries, and staking. The present property position is shown in Figure 4-2 and concessions are listed in Table 4-1.
Some of the mining concessions that form the Grupo Minero and one ancillary mining concession are subject to a contractual royalty of 1.5% NSR (Taca Taca Royalty). Franco Nevada Corp., through a wholly-owned subsidiary, holds the right to receive a 72% interest in the Taca Taca Royalty, and the remaining 28% interest is held by two individuals. A number of additional mining concessions are subject to contractual royalties of up to 1.5% of NSR. Table 4-1 includes a summary of the contractual royalties that apply with respect to the mining properties and rights comprising the Taca Taca property.
A royalty of up to 3% net of smelting/refining, transportation, administrative, and plant processing costs (also known as the “mine mouth” value) is payable to the Province of Salta.
Existing surface rights are adequate for the facilities planned for the Project at this time.
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4.3 Environmental Liabilities and Permitting
The 1995 Environmental Protection Mining Code of Argentina requires that each Provincial government monitor and enforce the laws pertaining to sustainable development and protection of the environment. A party that wants to modify or begin any mining-related activity as defined by the Mining Code (prospecting, exploration, exploitation, development, preparation, extraction, storage of mineral substances, property abandonment, or mine closure activity) must submit an application to the Provincial Environmental Management Unit (PEMU) and obtain an approved Informe de Impacto Ambiental or Environmental Impact Assessment (EIA) prior to the start of work (Bastida, 2002). Each EIA must describe the nature of the proposed work, its potential risk to the environment, and the measures that will be taken to mitigate that risk. The PEMU has a 60-day period to review and either approve or reject the EIA; however, if the PEMU has not responded within 60 days, that does not constitute an approval (Bastida, 2002). If the PEMU deems that the EIA does not have sufficient content or scope, the party submitting the EIA is granted 30 days to resubmit their document.
If accepted by the PEMU, the EIA is used as the basis to create a Declaración de Impacto Ambiental or Declaration of Environmental Impact (DEI) to which the party must swear to uphold during the mining-related activity in question. The DEI must be updated at least once every two years. Sanctions and penalties for DEI non-compliance are outlined in the Environmental Protection Mining Code, and may include warnings; fines; a suspension of the Environmental Quality Certification; restoration of the environment; temporary or permanent closure of activities; and/or, removal of authorization to conduct mining-related activities.
CASA filed updated EIA documents and received approval to proceed with the 2010, 2011, and 2012 drilling programs.
The permitting requirements anticipated to develop and operate the Project were developed by Vector Argentina with input from Argentine legal counsel. Together, they produced the “Taca Taca Permitting Handbook”, which is intended as a guide to permitting. The overall permitting timeframe is expected to take 12-18 months.
There are no known environmental liabilities currently existing on the Taca Taca property. In the unlikely case of abandonment of the mineral rights, closure activities may require restorative action to the original surface: filling trenches and removing the drill platforms.
Environmental and permitting activities are discussed in more detail in Item 20.0.
4.4 Other Significant Factors and Risks Affecting Access or Title
The Qualified Persons of this Technical Report are unaware of any other significant factors and risks that may affect access, title, or the right or ability to perform work on the property.
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5 Accessibility, Climate, Local Resources, Infrastructure, & Physiography
5.1 Location and Access
The Project is located in the remote Puna (Altiplano) region of Salta Province in northwest Argentina at an approximate elevation of 3,585 masl. The center of the Project is at latitude 24.7oS and longitude 68.0oW. The UTM coordinates are 7283500 N and 2628000 E (geographic projection: Gauss-Kruger POSGAR 94/Argentina WGS84, Zone 2).
Access by road and rail to the Project is discussed in detail in Item 5.5.
5.2 Physiography and Vegetation
The Project is located in the Puna (Altiplano) region of western Salta Province. It is located on the east side of the Sierra de Taca Taca and the western edge of the Salar de Arizaro. The topographic relief is low to moderate and has two prominent 3,700 m hills: Cerro de Cobre and Cerro Agua del Desierto. The Salar de Arizaro is at an elevation of 3,470 m. The property has many flat areas to accommodate a variety of site layouts.
Vegetation is sparse to nonexistent in the Project area.
5.3 Climate and Topography
The Project is located next to the Salar de Arizaro. Most of the surrounding terrain is rugged and steep, typical of the central Andean Altiplano, known as the Puna in Argentina. The elevations of the property range from approximately 3,480 to 3,770 masl, and approximately 30 km to the north is the volcano Cerro Aracar.
The climatic data for the area is limited and new meteorological stations at Quevar and Rio Grande have only been in operation for the last three to four years and are privately owned. Lumina Copper installed a weather station at the Project in 2010.
Site data has been compared to historical data for the region to develop the Project climatology. The climate for the Project is typical for the region; very arid with a low average annual precipitation of approximately 110 mm/y and high annual potential evaporation rate of 2,500 mm/y (calculated). The average relative humidity is approximately 34% and temperatures range from -110C to 200C, with January being the warmest month and July being the coldest month. Wind speeds range from 3.8 to 23.2 m/s, predominantly from the northwest. Although westerly winds are generally strong, particularly during the winter months, exploration activities can be carried out year round and are not significantly hindered by local climatic conditions.
5.4 Local Resources
The village of Tolar Grande (population under 150) is located 35 km east of the Project. Tolar Grande may provide some manual labour, housing and cooking facilities. The city of Salta (population 535,000) is the nearest major centre in Argentina and can provide basic goods and services for all stages of exploration and mining. Salta’s airport receives daily flights from Buenos Aires and numerous other destinations in Argentina. The city of Antofagasta, Chile, which is approximately 470 km west of the Project, has a deep-water port that is used by many mines in northern Chile.
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5.5 Regional Infrastructure
Although the Project is located in a remote area of northwestern Argentina, there is reasonably good access to regional infrastructure. A network of paved and gravel roads from Salta to the towns of San Antonio de los Cobres and Tolar Grande provide road access to the Project. The road continues 55 km west beyond the Project to the Socompa Pass on the Chilean border and eventually to the port city of Antofagasta, Chile.
The Project is located within 10 km of the railway line that connects Salta with Antofagasta. Rehabilitation of approximately 40 km of track between the Project and Socompa will be required, but it is envisioned that this railway will be used for concentrate transport to Chile and that consumables may also be transported by empty railcars returning to the Project.
Electrical connection to the national power grid is available at the Olacapato substation along the existing Guemes-Chile 345 kV transmission line, north of the Project. A new 144 km long 345 kV electrical transmission line from Olacapato to the Project is proposed.
Although the region is arid, subsurface water is available in the local area. A water supply study and water balance analysis were completed for the Project and based on these studies, the processing water flow sheet shows that there are adequate sources of water available for the Project. Additional prospective areas have recently been identified near the Project that may be sources of additional fresh water, which could further optimize the process water flow sheet.
It is expected that the Project’s water requirements can be met through accessing this subsurface water from a series of well fields. It has been assumed that water with varying amounts of salinity and total dissolved solids (TDS) will be pumped from multiple wells at three sites in HDPE pipe to process water tanks at the concentrator. A water treatment plant using reverse osmosis, as well as settling ponds, chlorination systems, and multi-media filtration is contemplated for the Project.
Project infrastructure is described in detail in Item 18.0.
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6 History
Previous exploration on the Taca Taca property is summarized in Table 6-1 and discussed in more detail in Amended Taca Taca Technical Report (SIM, 2010).
Table 6-1: Exploration and Ownership History of the Taca Taca Project
Year Company Description
Fabricaciones Late 1960s Discovery of porphyry copper mineralization at Taca Taca. Militares 1975 Falconbridge Drilled three holes into leach cap and abandoned property. Taca Taca S.A. (TACSA) acquired tenements over Taca Taca prospect, entered into an exploration agreement with Recursos Americanos Argentinos (RAA) and explored the property with GAMSA, 1990-1995 GAMSA (Gencor) a subsidiary of Gencor. Drilled 18 RC holes. Tested porphyry copper mineralization and an area of copper-gold veins north of the porphyry zone. GAMSA returned the property to RAA, who in turn returned the property to TACSA in 1995. Corriente Resources Inc. (Corriente) signed an exploration agreement 1995 Corriente with TACSA. Corriente formed a joint venture with BHP Minerals (BHP) in 1996. Mapping, geophysics (36.8 km of TEM surveying), geochemistry, and 1996-1997 Corriente/BHP drilling. Discovered supergene mineralization at base of leach cap. Target did not meet BHP’s corporate criteria and the property was returned to Corriente in 1997. Corriente acquired all shares of TACSA, which merged into Corriente Argentina S.A. (CASA). Mapping, trenching (130 backhoe trenches), 1998-1999 CASA geochemistry, and drilling. Tested for shallow supergene and exotic copper mineralization. Rio Tinto options property from CASA. Mapping, geophysics [ground magnetics (136 km), radiometrics (K/Th)], and drilling, Tested for 1999 Rio Tinto remnant oxide copper, supergene and exotic copper. Targets did not meet Rio Tinto size criteria, option with CASA terminated in 1999. Acquires property after acquiring 100% interest in CASA, sampling of 2003 Lumina Copper (1) surface oxide copper zones. Acquires property after corporate reorganization of Lumina Copper 2005 Global Copper Corp.(1) Rio Tinto options property from Global Copper. Mapping, radiometric dating, spectral analysis, and drilling. Tested for deep hypogene 2007 Rio Tinto copper-molybdenum mineralization. Results of drilling unfavourable and property returned to Global Copper. Acquires property when Global Copper transferred its assets 2008 Lumina Copper (2) (excluding the Relincho Project) to Lumina Copper prior to being acquired by Teck Resources Limited. Lumina On 19 August 2012, Lumina Copper became the beneficial owner of all 2012 Copper/CASA issued and outstanding shares of CASA.
(1) Lumina Copper Corp. formed in 2003, reorganized in 2005, and changed name to Regalito Copper Corp. (2) Lumina Copper Corp. formed in August 2008.
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Additional details concerning exploration and drilling are presented in Items 9.0 and 10.0 of this Technical Report.
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7 Geological Setting and Mineralization
7.1 Regional Geology
The Taca Taca porphyry copper-gold-molybdenum deposit is hosted in the southern half of a 50 km long Ordovician batholith, which forms the Sierra de Taca Taca mountain range (Figure 7-1). The batholith consists of coarse-grained granite that is cut by several aplite dykes. This Early Paleozoic intrusion is intruded by Late Permian granites and aplites and overlain by Late Permian sediments and volcaniclastics. Narrow, north-south striking, steeply dipping rhyolitic dykes of Permo-Triassic age outcrop throughout the region. Oligocene rhyodacitic intrusions of the Santa Inés Formation are responsible for the porphyry copper mineralization and alteration at Taca Taca.
Late Tertiary red-bed sedimentary rocks are widely distributed in the region, but are most abundant east of Salar de Arizaro. These rocks possibly constitute the basal section of the sedimentary sequence that fills the salar basin. Lavas from recent (Pliocene to Pleistocene) volcanoes are exposed to the west and north of Taca Taca. Large evaporite deposits of alternating salts and sand were deposited in regional intermontane basins to form the present-day salars (Almandoz, 2008).
The Sierra de Taca Taca is interpreted to be an uplifted block of Paleozoic intrusive rocks. Oligocene volcanics that are exposed to the west of the property dip to the west. This suggests that the Sierra de Taca Taca was uplifted with an eastern convergence along a major, high angle reverse fault located near the western border of the Salar de Arizaro. Regional evidence suggests uplift occurred during the Oligocene (Almandoz, 2008).
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Figure 7-1: Regional Geology (Almandoz, 2008)
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7.2 Local and Property Geology
7.2.1 Lithology The surface geology of the Taca Taca property is presented in Figure 7-2.
Figure 7-2: Surface Geology of the Taca Taca Project (Almandoz, 2008)
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The Taca Taca deposit is hosted by pink, coarse grained, porphyritic granite (Chavez, 2008) or granodiorite (Cornejo, 2008) of Ordovician age (441.5 +/- 3.4 Ma U-Pb date from zircons). It exhibits an equigranular texture and is composed of phenocrysts of plagioclase, quartz (2-4 mm “eyes”), K feldspar, and rare rutile after amphibole and biotite. This intrusion is cut by several aplitic and aplo- granitic dykes that formed at the same time as the Ordovician granites. Minor foliated dolerite dykes are interpreted as the final stage in the formation of the Ordovician batholith (Sillitoe, 2008).
Narrow, north-south striking rhyolitic dykes occur mainly in the eastern part of the Project and minor thin acidic dykes occur in the west part of the Project. These are related to the Choiyoi volcanic event of Permo-Triassic age (262.4 +/- 2.3 Ma U-Pb date from zircons).
These older lithologies are cut by a number of northeast-southwest striking, steeply dipping porphyritic rhyodacitic dykes which coalesce at shallow depths and are interpreted as the source pluton for the porphyry mineralization. These dykes have an Oligocene age (29.30+/-0.57 Ma-U/Pb date from zircons) which is contemporaneous with the porphyry copper mineralization. This lithology is characterized by large plagioclase, K-feldspar, and quartz phenocrysts.
Two different Oligocene intrusive events were recognized:
1. Early-stage rhyodacite that is characterized by crowded phenocrysts (up to 1 cm) of feldspar and quartz hosted in a biotite-rich groundmass. This unit has a strongly developed stockwork of early white to grey quartz veins.
2. Late-stage intermineral rhyodacite is characterized by fewer phenocrysts of feldspar and quartz, an aplitic groundmass and quartz veinlet xenoliths. This unit has a weakly developed quartz stockwork.
Both rhyodacitic phases are strongly altered, but have low-grade copper mineralization.
7.2.2 Alteration
Hypogene Alteration
Hydrothermal alteration associated with the Taca Taca copper-gold-molybdenum porphyry is typical of the Andean porphyry systems. Alteration types include potassic, propylitic, and phyllic, beginning with the earliest phase and progressing to assemblages that overlap or occur later in the development of the hydrothermal system, respectively. Descriptions of the following alterations are taken from Almandoz (2008).
Potassic: This is characterized by abundant, flaky, secondary biotite replacement of mafic minerals and rare secondary K feldspar that occurs as selvages of early veins. Potassic alteration occurs as remnant rafts in the central part of the mineralized zone due to a strong phyllic (sericite-quartz) alteration overprint.
Propylitic: It is characterized by illite-chlorite alteration of feldspars and mafic minerals with minor epidote alteration of plagioclase. Pyrite is common and varies 3-5%, although locally can be up to 10%. Propylitic alteration occurs on the peripheral edges of the hydrothermal system.
Phyllic: Phyllic (sericite-quartz) alteration is the most widely distributed and pervasive alteration phase associated with the Taca Taca porphyry copper-gold-molybdenum mineralization. It is exposed over an area measuring 3.5 km by 2 km. Two stages of phyllic alteration are present:
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An early phase is characterized by the presence of pale green sericite and quartz. The pale green sericite is related to an intermediate sulphidation mineral assemblage, which is characterized by chalcopyrite, minor pink bornite, and virtually no pyrite. The highest hypogene copper grades are directly associated with this alteration type. A late phase of phyllic alteration overprints potassic, propylitic, and green sericite phyllic alteration phases. It is characterized by coarse white sericite that completely replaces feldspar and mafic minerals. Pyrite commonly occurs as disseminations and in veinlets. The white sericite indicates a change in the sulphidation state of the mineralizing fluid from intermediate to high sulphidation. This change of sulphidation may be explained by cooler temperatures which produce more acidic, hydrothermal fluids.
Supergene Argillic Alteration
A well-developed, thick (150-300 m) leach cap overlies the porphyry copper-gold-molybdenum mineralization. It is characterized by abundant secondary kaolinite and hematite-jarosite fractures that replaced pre-existing sulphide veins. Copper oxides are rare although brochantite is common at the base of the leach cap and within a restricted area about the summit of Cerro de Cobre. The base of the leach cap is sub-horizontal and well-defined. A number of sub-vertical structures with supergene alteration were seen at depths up to 800 m below the surface. Secondary kaolinite, silica (chalcedony), alunite, and chalcocite are present in these structures.
7.3 Mineralization
There are three main styles of mineralization associated with the Taca Taca copper-gold- molybdenum porphyry: supergene/hypogene porphyry copper mineralization, remnant oxide copper-gold mineralization in the leach cap and hematite-quartz copper-gold veins. Each style of mineralization is discussed in more detail within this section.
Re-Os dating of the molybdenite has shown that the porphyry mineralization is Oligocene in age. The paragenesis of the mineralization and rock units is summarized in Figure 7-3.
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Figure 7-3: Paragenesis of Mineralization at Taca Taca (Almandoz, 2008)
Supergene/Hypogene Porphyry Copper Mineralization
Hypogene sulphide mineralization consists of chalcopyrite and pyrite with lesser bornite, chalcocite, digenite, and molybdenite occurring as disseminations and in quartz vein stockworks. Most of the copper mineralization is hosted by Ordovician granite and associated aplite and aplogranite dykes. Minor dolerite dikes have high copper contents due to the abundance of mafic minerals containing ferrous iron, which facilitates the precipitation of copper from the hydrothermal solutions. Molybdenite is more common in the aplite dykes than the granite and occurs primarily in early quartz veins. In the central part of the system, total sulphide content is relatively low ranging from 3% to 5%. A pyritic shell with up to 10% sulphide content is peripheral to the copper-molybdenum hypogene core (Almandoz, 2008). Based on the present drilling, the hypogene porphyry mineralization has a northeasterly trend with dimensions of 3.0 km north-south by 2.7 km east-west (Figure 7-4). The sulphide mineralization remains open at depth in some areas and along the southern boundary of the deposit’s northeastern limb.
The relationship of the hypogene sulphide zone to the overlying supergene enriched zone and leach cap is shown in Figure 7-5.
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Figure 7-4: Extent of Hypogene Sulphide Mineralization (Wells, 2012)
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Figure 7-5: Vertical East-West Oriented Cross Section 728 3950 N (Wells, 2012)
In the potassic alteration phase, minor chalcopyrite with subordinate bornite is associated with secondary biotite. The strong “A” type quartz vein stockwork is essentially barren of sulphides. Milky quartz “B” veins commonly contain molybdenite with subordinate chalcopyrite.
The two phases of phyllic (quartz-sericite) alteration are associated with the highest hypogene copper and gold grades. The sulphides are commonly disseminated in sericitic vein selvages, microfractures, and intergrown with the quartz veins. The early green sericite is associated with chalcopyrite-bornite and has the highest copper grades and above-average gold grades. The green sericite is a high temperature mineral associated with low sulphidation mineral assemblages. The late quartz and white sericite phase is associated with pyrite-bornite and pyrite-chalcocite-covellite sulphide assemblages. Copper grades decrease slightly and the gold grades are approximately half that seen in the early green phyllic alteration phase. The white sericite is formed at lower temperatures and is associated with the high sulphidation mineral assemblages.
In the central part of the porphyry system, the leach cap is strongly developed, but the supergene enrichment blanket is thin (< 5 m) or virtually absent. Two thicker zones (> 100 m) of supergene copper enrichment are present (Figure 7-6). One zone is associated with the West Fault and the second is located in the northeastern part of the deposit. The northeastern zone is up to 300 m thick. Copper mineralization in the Supergene Zones is dominantly fine-grained, black chalcocite with minor covellite. In addition to the stratiform supergene enrichment zones, several deep (> 500 m), steeply dipping supergene enriched structures were identified.
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Figure 7-6: Extent of Supergene Enrichment Zone (Wells, 2012)
Remnant Oxide Copper-Gold Mineralization in the Leach Cap
The leached portion of the porphyry deposit, which ranges from 150-300 m thick, is almost completely depleted of copper mineralization and is dominated by limonite assemblages consisting of hematite, jarosite, and goethite. Remnant zones of copper oxide mineralization consisting of malachite, chrysocolla, atacamite, and brochantite are present, but are limited to small sub- horizontal lenses up to several tens of metres in size. Concentrations of molybdenite and gold, being relatively immobile in supergene weathering environments, are approximately the same as that present in the hypogene zone. Reverse circulation (RC) drilling has helped define the extent of
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the gold mineralization in the Leach Zone. In general, the highest gold concentrations occur in the thickest portions of the leach cap and above the best hypogene copper-molybdenum mineralization.
The extent of gold mineralization with grades > 0.2 g/t in the leach cap is shown in Figure 7-7.
Figure 7-7: Extent of Gold in Leach Cap (Wells, 2012)
Hematite-Quartz Copper-Gold Vein Mineralization
Numerous parallel, north-striking and steeply dipping quartz-pyrite veins that were oxidized to quartz-jarosite and quartz-hematite veins occur in the Planicie Norte and Oeste areas (Figure 7-8). The veins are 0.5 m to 2 m thick and consist of quartz with massive to semi-massive pyrite or hematite-jarosite with minor alunite. Chalcocite coatings on the sulphides are common. In the surface exposures, chrysocolla and brochantite occur as weathering products of the chalcocite coatings. Argillic alteration envelopes, comprised of sericite and kaolinite, commonly extend several metres from the veins. Copper found in this zone is secondary in nature, apparently having
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migrated northward from the porphyry and re-precipitated on sulphide grains associated with the vein’s alteration selvages as well as within distal pyrite-bearing alteration phases (largely propylitic). A subsidiary of Corriente Resources explored these veins by trenching and shallow drilling. Significant supergene copper mineralization was found in this area by deeper drilling; it remains partially open. Note that there are no resources derived from these gold-copper, quartz-hematite veins included in the mineral resources listed in Item 14.0.
Figure 7-8: Hematite Copper-Gold Veins (Wells, 2012)
7.4 Structure
The structural fabric of the Ordovician granitic host rock is characterized by the presence of discrete but widespread north-northeast and northwest trending, steeply dipping proto-mylonite to mylonite
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zones. The emplacement of the Oligocene rhyodacitic dykes, quartz veining related to the porphyry system, fractures, and small-scale faults were controlled by these pre-existing zones of structural weakness.
A vertical, north-northwest striking, normal fault (West Fault) is located in the western part of the Project. The rocks to the west of the fault have a thinner leach zone and are uplifted relative to those in the east. This normal fault was probably active during Miocene times and may have controlled development of a zone of supergene copper enrichment associated with the structure.
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8 Deposit Types
Mineralization at the Project is a typical Andean porphyry copper-gold-molybdenum deposit (Lowell and Guilbert, 1970 and Pantaleyev, 1995). Common features of a porphyry deposit include the following:
Large zones (> 10 km2) of hydrothermally altered rocks that commonly grade from a central potassic core to peripheral phyllic, argillic, and propylitic altered zones. Generally low-grade mineralization consisting of disseminated, fracture, veinlet, and quartz stockwork-controlled sulphide mineralization. Deposit boundaries are determined by economic factors that outline the mineralized zones. Mineralization commonly zoned with a chalcopyrite-bornite-molybdenite core and peripheral chalcopyrite-pyrite and pyrite. Enrichment of primary copper mineralization by late-stage hypogene high sulphidation events can sometimes occur. Important geological controls on porphyry mineralization that include igneous contacts, cupolas, and the uppermost, bifurcating parts of stocks and dyke swarms. Intrusive and hydrothermal breccias and zones of intensely developed fracturing, due to coincident or intersecting multiple mineralized fracture sets that commonly coincide with the highest metal concentrations. Modification by surface oxidation in weathered environments (for example, Escondida). Low pH meteoric waters generated by the oxidation of iron sulphides, leach copper from hypogene copper sulphides, and oxidized copper minerals such as malachite, chrysocolla, and brochantite and re-deposit copper as secondary chalcocite and covellite immediately below the water table in flat tabular zones of supergene enrichment. The process results in a copper-poor leach cap lying above a relatively thin but high-grade zone of supergene enrichment that caps a thicker zone of moderate grade primary hypogene mineralization. Presence of precious-metal-rich epithermal, and other quartz vein systems, skarns, and exotic secondary copper deposits formed by the lateral migration of metal in low pH fluids away from the main body of porphyry mineralization.
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9 Exploration
Copper-gold-molybdenum porphyry-style mineralization was discovered at the Project in the late 1960s. Since that time, six companies have explored the property completing seven drilling campaigns. These campaigns are summarized in Table 10-1 and Figure 10-1 shows the location of the drill hole collars.
A more detailed review of the historic work is provided in Amended Taca Taca Technical Report NI 43-101 (Sim, 2010) and discussed in Item 6.0. A summary of significant results is included in the following sections.
9.1 Historic Exploration Programs (Non-Drilling)
BHP Minerals (1996-1997)
In 1995, Corriente Resources acquired the property and formed a joint venture with BHP. BHP carried out mapping, geophysical surveys (TEM and IP), and drilling. They outlined a large zone of supergene chalcocite and covellite enrichment on the northwest side of the core of the porphyry mineralization. The enrichment zone lies beneath 200 m to 300 m of leach cap and ranges from 20 m to almost 200 m thick. An estimate of the resource in the supergene blanket was made, but the tonnage was considered too small to meet corporate objectives. The property was returned to Corriente Resources.
Corriente Resources (1998-1999)(CASA)
In 1998 and 1999, Corriente Resources’ exploration activities focused on the gold-copper, quartz- hematite (pyrite at depth) veins located north of the porphyry leach cap. Exploration work included ground magnetic and radiometric surveys, excavator trenching, geochemical sampling, and drilling. Best results were obtained in the Planicie Norte area (for example, hole TK-53: 1.31% Cu and 3.32 g/t Au over 24 m core length). Similar but lower grade mineralization was encountered in the Planicie Oeste area (for example, TK-59: 0.88% Cu and 0.24 g/t Au over 26 m core length).
In 1999, Corriente Resources explored for an exotic copper deposit associated with the Taca Taca porphyry system. They conducted salar sand geochemical and gravity surveys to identify drill targets beneath the Salar de Arizaro.
Rio Tinto (1999 and 2008)
In 1999, Rio Tinto explored for zones of unleached copper oxides and/or unleached “perched” supergene enrichment zones within the near surface portion of the porphyry system at the Project. Evidence of this type of mineralization consisted of mineralized outcrops, trenches, and road cuts. Based on the results of a small seven-hole drill program, Río Tinto concluded that the extent of remnant oxide/supergene mineralization within the leach cap was not large enough to meet their corporate target.
9.2 Exploration by Lumina Copper (2010 - 2012)
In 2010, Quantec Geoscience, on behalf of Lumina Copper, completed a Titan 24 survey over the Taca Taca porphyry mineralized zone to look for deep areas of sulphide enrichment. The survey
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was done on four north-east-oriented lines (5 km long) spaced at 400 m intervals. Several deep IP and MT targets were defined and provided some early targets for Lumina Copper’s drilling campaign (Figure 9-1).
Figure 9-1: Titan 24 IP and MT Anomalies (Sim, 2011)
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10 Drilling
10.1 Drilling
Six different companies have completed seven drilling campaigns at the Project. These campaigns are summarized in Table 10-1 and Figure 10-1 shows the location of the drill hole collars.
Table 10-1: Drilling History
NUMBER HOLE TOTAL TYPE OF COMPANY YEAR METRES SERIES HOLES
Falconbridge TT01-03 BQ Core 3 529 1975 Argentina S.A.
Gatro Argentina TL01-08 RC 18 1,603 1995 Minera S.A.
TK001-033 RC, NQ core 35 11,483 BHP Minerals 1997
Corriente TK034-047 NQ core 14 3,246 1998 Resources
Corriente TK048-126 RC 80 4,428 1999 Resources
CCR001-007 RC 7 2,732 Rio Tinto 1999
ARI001-002 RC 2 606 Rio Tinto 1999
TTBJ0001-0008 HQ core 8 4,877 Rio Tinto 2008
TTBJ10-01 - 12-136 HQ core 137 89,058 Lumina Copper 2010-2012
TTRC11-01 - 12-97 RC 97 32,055 Lumina Copper 2011-2012
TTEX-01 - 07 HQ core 4 1,696 Lumina Copper 2011
TTGT-01 - 04 HQ core 4 2,404 Lumina Copper 2011
T7 – 21, GW3 HQ core 15 2,206 Lumina Copper 2011-2012
TTTV1 - 11, TW6 HQ core 12 6,094 Lumina Copper 2012
AV-SP4D - 5S HQ core 4 520 Lumina Copper 2012
TOTAL 440 163,537
A total of 440 holes (163,537 m) have been drilled on the Taca Taca property. From 2010 to 2012, Lumina Copper drilled 273 holes (134,033 m). The mineral resource model is based on 310 drill holes (147,449 m) which tested the extent of the known porphyry mineralization.
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Figure 10-1: Drill Collar Plan Map – Taca Taca Project (Wells, 2012)
10.2 Historic Drilling
In 1975, Falconbridge drilled three short holes into the leach cap, but did not intersect any significant mineralization. Core from this phase of drilling was discarded. The collars of these holes have been found in the field and the locations have been confirmed through surveying.
Gatro Argentina Minera S.A. (GAMSA)
In 1994, GAMSA drilled 18 short RC holes that targeted epithermal gold mineralization in the Planicie Norte area and porphyry-style mineralization associated with the leach cap. No significant mineralization was encountered and they dropped the property in 1995. Cuttings from the RC holes were discarded; however, the location of some of these holes was confirmed.
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BHP Minerals
In 1997, BHP tested the potential for a zone of supergene enrichment beneath the leached cap of the Taca Taca porphyry system. Thirty-five combined RC and NQ diamond drill (DD) holes (TK 001- 033) with a total length of 11,483 m were completed on a 400 m x 400 m grid pattern; this includes two holes, TK015A and 30A, which were abandoned and redrilled. Most of these holes were vertical and their lengths ranged between 91-520 m. Drill core from this program is stored at CASA’s secure core storage facility in Salta. Cuttings from the RC section of the holes were discarded. Drill hole locations were confirmed.
Corriente Resources
In 1998, Corriente Resources drilled 14 NQ DD holes (TK034-047) to test for the presence of shallow supergene enrichment zones in the Planicie Norte area. Most of these holes were drilled to the east at dips of -60°, but a few holes were vertical. The holes ranged between 120-406 m deep. Drill core from this program no longer exists, but the drill hole locations were confirmed.
In 1999, Corriente Resources drilled 80 RC holes (TK048-126) totalling 4,428 m in four different areas: Planicie Norte, Planicie Oeste, the Graben area, and beneath the Salar de Arizaro. The target in all four areas was exotic copper mineralization. The holes were drilled at dips ranging between vertical and -60°, and to depths ranging between 15 m and 117 m. Cuttings from these RC holes are no longer available. Drill hole locations were confirmed.
Rio Tinto
In 1999, Río Tinto completed nine RC drill holes in two different areas. Seven of the holes (CCR001-007), with lengths between 360 m and 408 m, and totalling 2,732 m, were targeted on remnant oxide mineralization within the leach cap in the central portion of the Taca Taca porphyry system. The other two holes (ARI001 and ARI002) were drilled to the east of Taca Taca to explore for exotic copper mineralization underlying the Salar de Arizaro. The RC cuttings are no longer available. Drill hole locations were confirmed.
In 2008, Rio Tinto completed eight HQ drill holes totalling 4,877 m, which targeted deep hypogene mineralization. Major Perforaciones Argentina provided the drilling services using an AVD 600 machine. Drill core from this program is stored at CASA’s secure core storage facility in Salta. Drill hole locations were confirmed.
10.3 Drilling by Lumina Copper (2010-2012)
In 2010, Lumina Copper began a 99,500 m DD program to test the extent of porphyry copper mineralization at the Project and to assess the significance of the Titan 24 anomalies.
During the 2010 field season, Major Perforaciones of Mendoza (Major) was contracted to provide drilling services. They provided one skid-mounted ED50 diamond drill rig. The drilling began on August 3, 2010 and five holes were completed in 2010.
The early drilling discovered extensive porphyry-style supergene and deep hypogene copper mineralization over an area of 2.5 km by 1.5 km. The exploration drilling program was redesigned and expanded to meet the following objectives:
Delineate the shape and thickness of the supergene enrichment blankets.
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Assess the extent and potential for high-grade hypogene mineralization in the deeper parts of the porphyry system. Evaluate the gold potential of the leach cap.
Drilling continued until September 2012, with up to seven diamond drills operating on the property. Core drills were supplied by Major, Boart Longyear, and Alta Drilling. Two Schramm T685 WS-C RC rotary rigs from Major were used to evaluate the gold potential of the leach cap and provide pre- collars for the diamond drilling. Since 2010, Lumina Copper has completed 273 holes totaling 134,033 m.
REFLEX or Peewee survey tools were used to provide downhole orientation data for the DD holes. All collar locations were initially located using a handheld GPS (Garmin 60CSx), but, after the hole was completed, the collar location is surveyed using a differential Trimble GPS, accurate to +/- 10 cm.
Drill core and RC rejects from this program are stored at CASA’s secure core storage facilities in Salta. For a further discussion of sampling, see Item 11.0.
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11 Sample Preparation, Analyses, and Security
11.1 Historic Drilling and Sample Preparation
Falconbridge and GAMSA
No written record of the sample preparation or analytical methods was available for the Falconbridge (1975 core hole) or GAMSA (1994 RC hole) drilling programs. There is also no record of any QA/QC protocols or results for these two drilling programs.
BHP Minerals
BHP cut the drill core in half using a diamond saw. One-half of the core was put into plastic sample bags and shipped for analysis, and the other half was retained as a permanent record. Most drill core was sampled using 2 m intervals. No written descriptions of any sampling methods for the RC drill campaigns were available for review. Sample cutting piles were observed at several collar locations during the site visit; this indicates the drill cuttings were probably split and sampled on-site before shipment to the assay lab. Samples were analyzed at Bondar Clegg in La Serena, American in Mendoza, and SGS in Salta and Santiago. The analytical methods and sample preparation protocols were not discussed in any of the BHP reports, but the results were presented in a spreadsheet format without original assay certificates. BHP’s quality control protocols involved submitting one-quarter core duplicate sample for every 20 samples and submitting them to the original laboratory and submitting 300 coarse reject duplicates to Bondar Clegg as check assays. The results of the duplicate sampling or coarse reject duplicates were not available for review.
Corriente Resources
Corriente Resources cut the drill core in half using a diamond saw and submitted half of the core for analysis at ALS Chemex Labs (ALS Chemex) in Mendoza. Corriente Resource’s sample preparation protocols were not available for review. Copper analyses were done using atomic absorption spectroscopy and gold was analyzed by fire assay with an atomic absorption spectroscopy finish. Corriente Resources did not collect quality control data, other than a routine submission of pulp duplicates to another lab for check analyses. The check lab data was not available for review.
Rio Tinto
1999
Samples from Río Tinto’s 1999 RC drilling program were prepared by Bondar Clegg’s laboratory in Mendoza using a “Large Pulp Preparation” procedure. The entire sample was crushed to -80 mesh and a 1 kg split of this material was pulverized. Bondar Clegg of Vancouver, Canada analyzed the samples for gold and 34 other elements using fire assay with an atomic absorption finish and total digestion ICP analysis, respectively.
Río Tinto carried out systematic QA/QC procedures. One field duplicate was inserted for approximately every 12 samples to check for splitting and lab errors. The samples were randomized and pulp duplicates, standards, and blanks were added. This QA/QC program adhered to accepted industry standards. Río Tinto’s QA/QC results were not analyzed in detail by Robert Sim, SIM Geological, but they were reviewed in graphical form. SIM Geological concluded that they appeared
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to support Río Tinto’s conclusion that “the analysis of the results obtained from the quality control indicates the lab’s performance was satisfactory” (Río Tinto, 1999).
2008
In 2008, Rio Tinto used the following procedures for the eight HQ drill holes:
Core Sampling
Core was placed in boxes by the drill crew and logged by the geology staff at the core shed. The sampling staff photographed the core and marked it with a line drawn down the centre. The core was cut along this line using a diamond rock saw. Samples were taken at 2 m intervals. Half the core was placed in a plastic bag for analysis, and the remaining half was placed back in the core box for reference. A lab-generated sample ticket was inserted in the plastic bag with the sample, and a second ticket was stapled into the throat of the bag. Nylon cable ties were used to seal the bags. The bags were taken from the sawing area to the core shed where the sample number was written on the bag. Each bag was weighed and up to five sample bags were sealed in a larger mesh sack. The sacks were sealed with a large, numbered cable tie and labelled “secured.” Samples were shipped only after all samples from one hole were complete.
Chain of Custody
The sample bags were checked onto the truck, an inventory was sent with the shipment, and a copy kept on-site. Samples were transported from site in a covered pick-up truck, driven by a Rio Tinto staff member. Any tampering with individual bags or bag ties would have been immediately evident when they arrived at the lab: the lab was notified of the sample numbers, and, on arrival, the lab sent confirmation of the samples being received and their condition. No irregularities in any sample shipment were detected during the course of the program.
During the 2008 visit, SIM Geological concluded that all procedures were carefully observed and met or they exceeded industry standards for the collection, handling, and transport of drill core samples.
Analyses
The drill core samples were analyzed by Alex Stewart (Assayers) Argentina S.A., Rodriguez Pena 1140, Luzuriaga, Maipu, M5516 BBX, Mendoza, Argentina. This lab is 9001:2000 certified.
The samples were analyzed for gold using a fire assay/atomic absorption finish on a 30 g charge. An additional 39 elements were analyzed by four acid digestion and an ICP finish; the elements included in the ICP package were: Ag, Al, As, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, Ga, Hg, K, La, Li, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, S, Sb, Sc, Se, Sn, Sr, Ta, Te, Ti, Tl, V, W, Y, Zn, and Zr. The copper over-limit values were analyzed by atomic absorption (AAS).
A suite of 133 inter-laboratory check samples was also assayed at ALS Chemex in Lima, Peru; this lab is also ISO 9001:2000 certified.
QA/QC Procedures
During the 2008 Rio Tinto drill program, the sampling staff inserted standards, blanks, and duplicates as specified by Rio Tinto site geologists. A standard was systematically inserted for every 25 core samples. A few (seven or eight) field duplicate samples, which consist of the other
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half of the drill core, were also taken. Blank material was inserted at the rate of one in every 20 samples. The blank material consisted of quartzite from a quarry in San Luis Province, Argentina. It was included in the form of rock chips (BLQZ) and pulverized material (BLKL) to test sample preparation and analysis, respectively. In addition, the lab analyzes a split of the coarse and pulp reject at a rate of one per 25 samples.
A suite of 133 pulp duplicate samples from hole TTBJ0003, including four samples of the Altar 3 Gold Standard Reference Material, was sent to ALS Chemex in Lima and analyzed using a comparable four-acid digestion with atomic absorption finish for copper and molybdenum and 30 gram fire assay finish for gold.
Results of QA/QC Work
A detailed review including charts and graphs of the QA/QC data from Rio Tinto’s eight drill holes were presented in Amended Taca Taca Technical Report NI 43-101 (Sim, 2010).
The results are summarized as follows:
Field duplicate samples were taken to check the geological variability of the sample size. Duplicate samples of coarse reject material were assayed to check the sample preparation protocol. If the protocol was adequate, 90% of the duplicate pairs of assays should fall within ± 30% of each other (pass). A comparison of field duplicate data and coarse reject duplicate data can be used to estimate geological variability. For copper and molybdenum, the sample preparation protocol appeared to be good. For molybdenum, the percentage of field duplicates falling within the ± 30% control limit was 86% which, given the small number of samples (seven), is not of concern and may indicate a higher geological variability than copper. Field duplicate results for gold, however, showed a poor reproducibility which improves markedly once the samples are crushed as indicated by the acceptable coarse reject duplicate results. This indicated that the high variability seen in field duplicate results may also be due to geological variability (also known as the nugget effect). For the pulp duplicates, over 90% of the pairs falling within ± 10% of each other is (control limit) considered adequate. Results obtained for the program indicated that the sample assay protocol was adequate for copper, but required review for gold and molybdenum. Rio Tinto used SRM for copper and gold. Most samples plotted within one standard deviation of the accepted values. Consequently, there were no significant issues with the copper or gold analyses. No reference material for molybdenum was specifically used, but the molybdenum results for the copper and gold standards indicated a consistency of results for both standards and no problems with analysis for this element was suspected. Blank results for copper, molybdenum, and gold were considered acceptable. Some contamination in the sample preparation stage was detected for copper and the five high values (> 100 ppm Cu) came from sample batches containing highly mineralized material ( 2.5% Cu). These spikes most likely resulted from sample to sample contamination at the jaw crusher stage. It was not thought to have affected many samples to a significant extent.
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Sample results for the inter-laboratory check samples were not available, but a visual inspection of graphs provided by Rio Tinto showed an excellent correlation for copper, a good correlation for molybdenum, and an acceptable correlation for gold. For copper, 97% of all checks returned a mean percentage difference of less than 10%. For molybdenum, 87% of all checks returned a mean percentage difference of less than 5%. For gold 72% of all checks returned a mean percentage difference that was less than 20% (Almandoz, 2008). Results from the four SRM samples submitted with this batch were not available, but Rio Tinto reported that results produced for gold were outside acceptable limits (Almandoz, 2008).
Conclusions
Results from SRM indicated that the copper, gold, and molybdenum assay procedures were producing reliable assay data. Blank results indicated that there may be a minor contamination of blank samples by copper, which probably occurred when high grade copper samples contaminated a few samples that followed them through the preparation stage. This was not thought to be significant for resource estimation purposes. Blank material indicated that there was no detectable contamination of the sample preparation or assay procedure for molybdenum and gold.
Duplicate data indicated that the sample preparation stage worked well for copper, molybdenum, and gold. The high variation in field duplicate data for gold indicated a high geological variability (nugget effect). Molybdenum field duplicate variation was not quite as high as for gold.
Inter-lab duplicates showed excellent, good, and acceptable reproducibility for copper, molybdenum, and gold, respectively.
Robert Sim and Bruce Davis concluded that Rio Tinto’s drill core sampling protocols at the Project are similar to industry standard procedures. No recovery information was available for review, but the recovery seemed good for the examined diamond drill core and there is no evidence that diamond drill or reverse circulation recovery could materially impact the drill results.
None of the preceding conclusions are sufficiently important to make the Rio Tinto results unreliable for publication, particularly considering that gold and molybdenum make only minor contributions to the value of the contained metal at present day metal prices. The influence of Rio Tinto’s drilling on the current mineral resource estimate is relatively minor due to the number and distribution of more recent drill holes completed by Lumina Copper.
11.2 Lumina Copper Drilling (2010-2012)
Lumina Copper used the following procedures during their 2010-2012 DD core and RC drill programs:
Core Sampling
The drill contractor places the HQ drill core into wooden boxes (1 m long by 3 rows) at the drill rig. Wooden tags marked with the downhole depth are placed in the box. Lids are placed on the box and it is transported by truck to the core shack. Upon receipt, Lumina Copper field assistants check the depth and mark out the samples at 2 m intervals. Photos are taken of both dry and wet core. Two boxes are included in each photo. Lumina Copper geologists and technicians examine the core and prepare geological and geotechnical logs for each hole. The geotechnical log includes: rock quality data (RQD), core recovery, fracture and vein quantity, vein angles, and density
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measurements. Samples are taken at 10 m intervals for point load tests and density measurements. This information is entered directly into an Excel® spreadsheet for each hole.
The core is cut in half using a diamond saw. For each 2 m sample, one-half is put into a plastic bag and the other half is returned to the wooden box for reference. Bar coded sample tags are included in each sample bag and the sample number is written in permanent marker on the sample box. Sample bags are secured and put into a larger mesh sack with a tamper-proof nylon tie. Duplicate and standard samples are included, as required. When a hole is complete, the samples are sent by truck to either ALS Chemex or Alex Stewart in Mendoza, Argentina.
The remaining core is initially stored on pallets at the exploration camp and then moved to CASA’s secure core storage facility in Salta.
RC Sampling
Lumina Copper geologists and assistants are present during the drilling of RC holes and they are responsible for taking the samples for assay. Samples are taken every 2 m. Cuttings are collected from the cyclone and placed directly into the Gilson adjustable sample splitter. The sample is split three times until there are two samples representing approximately 25% of the initial weight. Each sample weighs approximately 6-10 kg. One sample is sent to the lab for analysis and the other is stored for reference or future sampling. A small sample (100 g) is taken from the reject bag and placed on a chip strip where it is visually inspected and logged by a Lumina Copper geologist.
The Gilson adjustable sample splitter and all the tools used in the sampling process were cleaned with compressed air after every sample to reduce contamination.
Major water intersections encountered during drilling are noted by the geologist on site. Wet samples were split using a rotary wet splitter; one-half of the material was collected in a big bucket and left for a reasonable time to decant. After the water is removed, the sample is divided in two; one is sent to the assay lab and the other is put into storage.
Samples, duplicates, standards, and blanks from each hole are sorted at the exploration camp and transported directly to the ALS Chemex facility in Mendoza, Argentina.
Chain of Custody
Lumina Copper uses the same sample procedures as Rio Tinto did in 2008. The sample bags are checked onto the truck, and an inventory of samples is sent with the shipment and a copy is kept on-site. Any tampering with individual bags or bag ties would be immediately obvious when the samples arrived at the lab. The lab is notified of the sample numbers that were sent and on arrival the lab sends confirmation of the samples received and their condition. No irregularities in any sample shipment were detected during the course of the program.
During Bruce Davis’s site visit in 2012, he concluded that all procedures were being carefully observed and met or exceeded industry standards for the collection, handling, and transport of drill core samples.
Analyses
Samples from the Lumina Copper drill programs were sent to: ALS Geochemistry - Mendoza, Altos Hornos Zapla 1605, Mendoza Godoy Cruz, Argentina, (ALS) or Alex Stewart Argentina S.A., Carril Rodriguez Pena, M5516 Maipu, Mendoza, Argentina (Alex Stewart).
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Both analytical labs are ISO 9001:2008 certified. The samples were analyzed for gold using a fire assay/atomic absorption finish on a 30 g charge and for another 35 elements by four acid digestion and an ICP finish. The elements included in the ICP package are: Ag, Al, As, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, Ga, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sb, Sc, Se, Sn, Sr, Th, Ti, Tl, U, V, W, and Zn. Samples with copper values >10,000 ppm are analyzed by atomic absorption spectrometry.
QA/QC Procedures
The performance of ALS Chemex and Alex Stewart is monitored through the implementation of a QA/QC program. The results of this program are tracked by Lumina Copper and reviewed by Bruce Davis on an ongoing basis. Irregular or suspect results were addressed in a timely manner to ensure the integrity of the database.
Lumina Copper established a QA/QC protocol that uses reject duplicates, standards, and blanks inserted into the sample batches at regular intervals. Duplicates are inserted during sample preparation (independent from the assay laboratory) by splitting the pulps. A range of copper-gold- molybdenum SRMs, of suitable matrix composition, including blanks, is inserted by Lumina Copper during the core sampling procedure. The structure of this QA/QC program follows accepted industry standards.
There is at least one of the eleven different SRMs, plus duplicates and blanks (QA/QC samples), included in every batch. A QA/QC sample is inserted into the sample stream once every eight samples. The SRMs cover a broad range of copper-gold-molybdenum concentrations encountered at the Project and one is inserted every 24 samples sequentially independent of the blanks and duplicates. A duplicate is selected from samples with sufficient material and inserted once in every 24 samples. A blank is inserted once in every 24 samples. When smaller batches of samples are sent to the lab, containing insufficient samples to maintain this frequency, at least one of the eleven SRMs, a duplicate, or a blank are inserted.
Assay results for the copper, gold, and molybdenum are compared with the accepted values for standards and blanks. Duplicates are compared with original values. Example ALS Chemex control charts for the OREAS 50C SRM are shown in Figure 11-1 to Figure 11-3. The red lines indicate the upper and lower control limits (UCL and LCL) which are defined as ± 10% of the accepted value. The coarse blank for copper control chart appears in Figure 11-4. The UCL for blank material is three times the average detection value of all samples analyzed. The ALS Chemex coarse duplicate performance for copper is shown in Figure 11-5. UCL and LCL for coarse material are defined as ± 30% of the relative difference between both assay values.
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Taca Taca QC Results Through December 2012
OREAS 50C Copper
9000
UCL = 8162 8000
AVG = 7523 Cu ppm
7000 Accepted value = 7420 LCL = 6678
6000 0 100 200 300
Sequence Number
Figure 11-1: ALS Chemex OREAS 50C SRM Copper Control Chart
Figure 11-2: ALS Chemex OREAS 50C SRM Gold Control Chart
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Figure 11-3: ALS Chemex OREAS 50C SRM Molybdenum Control Chart
Figure 11-4: ALS Chemex Coarse Blank Copper Control Chart
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Figure 11-5: ALS Chemex Copper Coarse Duplicate Comparisons
Examples of the Alex Stewart control charts for the OREAS 503 SRM are shown in Figure 11-6 to Figure 11-8; OREAS 50C SRM examples were not available for use at Alex Stewart. The red lines indicate the upper and lower control limits (UCL and LCL) which are defined as ±10% of the accepted value. The coarse blank for copper control chart appears in Figure 11-9. The UCL for blank material is three times the average detection value of all samples analyzed. The Alex Stewart coarse duplicate performance for copper is shown in Figure 11-10. UCL and LCL for coarse material are defined as ± 30% of the relative difference between both assay values.
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Figure 11-6: Alex Stewart OREAS 503 SRM Copper Control Chart
Figure 11-7: Alex Stewart OREAS 503 SRM Gold Control Chart
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Figure 11-8: Alex Stewart OREAS 503 SRM Molybdenum Control Chart
Figure 11-9: Alex Stewart Coarse Blank Copper Control Chart
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Figure 11-10: Alex Stewart Copper Coarse Duplicate Comparisons
All abnormal quality control results were addressed by re-assaying remaining material. Whenever re-assaying was required, the remedial results replaced original assays. No QC failures remain in the database.
Suites of duplicate samples were exchanged between Alex Stewart and ALS. Comparisons of the inter-lab duplicates for copper show very good results with most differences attributed to samples in the low-grade range. Correlations between lab duplicates for gold and molybdenum are not as good, but these results are often attributed to the fact that many of the samples contain very low- grades for these elements. Overall, there is no indication of bias, but precision is generally poor due to the low-grade range of many of the samples. These results have little to no overall effect on the estimation of mineral resources.
Bruce Davis believes Lumina Copper’s drill core sampling protocols at the Project meet accepted industry standards. Recovery is good for the examined diamond drill core and there is no evidence that diamond drill or reverse circulation recovery could materially impact the drill results.
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12 Data Verification
12.1 Historic Drilling
Steve Blower, P.Geo, at AMEC’s Vancouver office, visited the Project in April 2003 and authored an NI 43-101 report on the Project dated May 2003. At that time, the data verification consisted of: a collection of several representative samples for independent check assays, a comparison of assay data stored in CASA’s database, and the original assay certificate records.
In 2003, 11 copper and gold check assays were completed on drill core samples collected during AMEC’s visit. The check sample intervals were randomly selected from both hypogene and supergene mineralization, using the same intervals as the previous exploration programs. Robert Sim reviewed this data and concluded both the gold and copper check assay results agree with the original assay results. Differences between the check and original results are small, and the check assays are not systematically higher or lower than the original assays.
Assays for 11 drill holes from Corriente Resources’ spreadsheet database files were checked against the results from the original paper assay certificates. The only certificates available were from Corriente Resources’ third phase of drilling (TK-048 to TK-126). The 11 holes represent 14% of the data in Corriente Resources’ phase 3 campaign, or 7% of the total assay database at the time. All of the assay results in the database were the same as the values on the original certificates.
Robert Sim reviewed AMEC’s validation work conducted on the sample data and he believes that the process and conclusions were appropriate to validate the data.
During property visits in July 2008 and June 2012, Robert Sim compared the assay results and the visual observations of the content of copper and molybdenum-bearing mineralogy in randomly selected intervals from several drill holes. The quantity and type of minerals observed support the assay results in all cases. Drilling activities were observed and numerous drill hole collars from previous drilling programs were seen while visiting the property.
12.2 Lumina Copper Drilling
Robert Sim compared the original assay certificates from ALS Chemex for ten holes from the recent Lumina Copper drilling and the assays listed in the electronic database. There were no errors noted in the database validation.
Robert Sim and Bruce Davis reviewed a series of randomly selected drill core intervals during their site visits in July 2008, January 2011, and June 2012. In all cases, the type and content of observed copper-bearing minerals supported the copper grades present in the database.
Given the assay check results, observation of the drilling and core sampling, and the comparison of certificates to the electronic database, the sample assay data is within acceptable limits of precision and accuracy to generate a mineral resource estimate.
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12.3 Conclusions
The Taca Taca database was derived from drilling programs conducted in the 1970s, 1990s, 2008, and 2010-2012. This data was verified using several methods including visual comparisons, resampling, and direct comparisons with assay certificates.
Industry accepted QA/QC programs have only been documented in the drilling programs conducted by Rio Tinto in 1999 and 2008, and by Lumina Copper in 2010-2012. The results of this work indicate that the data is sound. The fact that the drilling results prior to 1999 are not dissimilar to those obtained by Rio Tinto and Lumina Copper indicates this earlier data is also acceptable. Robert Sim and Bruce Davis believe that the sample database is sufficiently accurate and precise to generate estimates of mineral resources.
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13 Mineral Processing and Metallurgical Testing
13.1 General
Ausenco has reviewed Taca Taca metallurgical test reports and data to develop process design criteria for the PEA. The test work undertaken is reasonably extensive and considered suitable for this level of study. The comminution data are considered adequate for a conceptual milling circuit design. The design of the processing circuits is based on this test work data in conjunction with assumptions based on typical industry values.
The Taca Taca mineralized material is of moderate competency and hardness, and amenable to grinding in a conventional SAG-ball milling circuit with pebble crushing. The mineralogy is fine grained and test work indicates a requirement to re-grind to a fine particle size to achieve adequate liberation for flotation, as is common practice within the industry.
The Taca Taca concentrator envisions processing 120,000 t/d of ROM mineralized material initially, expanding to process 180,000 t/d in Year 8. Copper and molybdenum concentrates and tailings will be produced. The proposed process includes crushing and grinding of the ROM mineralized material, bulk copper-molybdenum rougher and cleaner flotation, regrinding, copper-molybdenum separation, molybdenum flotation, and dewatering of copper and molybdenum concentrates. The flotation tailings will be thickened before placement in a TSF.
13.2 Metallurgical Testing
The following metallurgical test reports provide the basis for this PEA:
Plenge Laboratory, Metallurgical Investigation No. 9281-9402, Lumina Copper Corporation Inc. Taca Taca Copper Gold Molybdenum Project Comminution, Copper Molybdenum Separation, Variability Oxide Copper and Gold, October 16, 2012; Starkey & Associates, S&A Project S117-1, Taca Taca Project SAGDesign® Comminution and Mill Sizing Analysis Report Rev 0, July 11,2012; and, JK Tech Pty Ltd. SMC Test Report (tested at C.H. Plenge, Lima Peru) Job No. 10199/P2 August 2010.
The Plenge program (October 2012) tested four composites from two material types, S1 and S2 (Supergene) and P1 and P2 (Primary), as defined by the April 2012 resource estimate. The samples were prepared to represent Years 1 to 5, identified as S1 and P1 and to represent Years 6-10, identified as S2 and P2.
The following tests were conducted:
Bond Crusher Work Index on Supergene and Primary samples Specific Gravity on Supergene and Primary samples SAGDesign® Test on Supergene and Primary composites Unconfined Compressive Strength (UCS) Tests on Supergene and Primary composites
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Bond Rod Mill Work Index on Supergene and Primary composites Abrasion Index on Supergene and Primary composites Grindability tests on Supergene and Primary variability samples Locked cycle tests on each composite S1, S2, P1, and P2 using tap water Locked cycle test using brine water in rougher flotation and tap water in bulk copper-moly concentrate flotation on each of the composites, and a 1:1 blend of Supergene + Primary (excluding copper and molybdenum separation) Locked cycle test using tap water on each of the composites, and a blend of Supergene + Primary (excluding copper and molybdenum separation) Rougher variability tests on 15 Supergene samples Rougher variability tests on 25 Primary samples Cleaner variability tests on 15 Supergene samples Cleaner variability tests on 25 Primary samples Rougher variability tests on each of the composites, and a 1:1 blend of Supergene + Primary Batch cleaner flotation tests on Supergene and Primary composites with different water blends for comparison. Varying the water used including 100% tap water, 25% pit water + 75% tap water, 50% pit water + 50% tap water, 75% pit water + 25% tap water Batch cleaner flotation test with tap water on Supergene + Primary blend composite Thickening and filtration tests on rougher tailings and copper concentrate products from the tap water locked cycle tests Thickening and filtration tests on rougher tailings product from Supergene variability tests Thickening and filtration tests on rougher tailings products from Primary variability tests
Comminution circuit design for Taca Taca was based on results from two JK Drop weight tests conducted in 2010 and the Bond Ball Work Index values from the variability samples and SAG Design®.
Locked cycle tests on each composite using tap water produced copper and molybdenum concentrates. Thickening tests using the Kynch method was performed on each of the copper concentrates and rougher tailings produced in each of the locked cycle tests. Pressure filtration tests were performed on each thickener flotation tailing sample and two tests on each copper concentrate from the locked cycle tests.
Ausenco has reviewed the location of the samples and drill holes and concludes the samples are reasonably representative of the deposit for a PEA given the nature and continuity of rock types and mineralization of the deposit.
Where no test work data are available, reasonable assumptions, based on operating data or test work from other projects has been used to develop the process design criteria used for the plant design.
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13.3 Comminution Test Work
Several comminution tests were conducted; the results are summarized in Table 13-1.
Table 13-1: Summary of Comminution Test Results
Supergene Primary Physical Property Unit Average 75th Percentile Average 75th Percentile
Bond Crusher Work Index kWh/t 6.65 - 8.11 -
Bond Ball Work Index kWh/t 17.33 19.06 15.75 16.20 (from SAGDesign®)
Bond Ball Work Index kWh/t 18.95 20.68 16.57 17.76
UCS MPa 12.24 12.71 12.84 14.61
Abrasion Index Ai (g) 0.200 0.213 0.230 0.241
Specific gravity g/cc 2.70 - 2.71 -
SAGDesign® tests were done on four Supergene composites and six Primary composites. The results are summarized in Table 13-2.
Table 13-2: Summary of SAGDesign® Results
SAGDesign® SAGDesign® Sample No. Sample No. (kWh/t) (kWh/t)
Supergene Primary
Supergene Comp 1 16.81 Primary Comp 1 14.99
Supergene Comp 2 15.03 Primary Comp 2 14.94
Supergene Comp 3 18.63 Primary Comp 2 16.08
Supergene Comp 4 20.36 Primary Comp 4 16.60
- - Primary Comp 5 16.29
- - Primary Comp 6 15.58
Average 17.33 Average 15.75
75th percentile 19.06 75th percentile 16.20
Compression tests were done on 25 rocks from each material type composite ranging in size from 13.2 to 16 mm. Bond Ball Work Index numbers were interpreted by comparison from the grindability test data for each material type, 15 Supergene samples and 25 Primary samples.
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Abrasion Index tests were conducted on four Supergene composites and six Primary composites.
In 2010, two samples were tested for competency using the JK Drop weight test. The results are summarized in Table 13-3. The value of Axb is a measure of resistance to impact breakage. Due to the low number of samples tested, Ausenco applied a 115% design factor to the Axb for the Primary material which was the most competent. In the future phases of the project there should be more variability testing on material competency to design the SAG circuit which is the higher capital cost area of the plant, as well as in some cases a crucial factor in achieving plant design throughput.
Table 13-3: JKTech – SMC Test Results
Sample No. A b. Axb Primary 66.9 0.91 60.9 Supergene 69.5 0.99 68.8 Design (applying 115% factor) 52.9
13.4 Flotation Test Work
13.4.1 Locked Cycle Tests using Tap Water
Four locked cycle tests using tap water throughout all phases of the test were performed. The results are summarized in Table 13-4.
Table 13-4: Summary of Locked Cycle Tests Using Tap Water
Concentrate Grade Concentrate Recovery % Wt Sample Name Au, % Cu, % Mo, % Au Cu Mo g/t
Supergene S1
Bulk Cu - Mo Concentrate 1.8 5.38 34.5 0.8 60.2 90.6 69.7
Cu Concentrate 1.8 5.6 35.3 0.13 57.8 87.9 8.0
Mo Concentrate 0.02 1.2 1.9 45.3 0.2 0.1 49.6
Supergene S2
Bulk Cu - Mo Concentrate 2.3 4.56 33.3 0.68 67.7 90.2 85.8
Cu Concentrate 2.2 4.5 32.8 0.15 64.1 86.2 13.6
Mo Concentrate 0.02 1.10 0.95 49.6 0.1 0.02 62.3
Primary P1
Bulk Cu - Mo Concentrate 2.11 6.4 28.4 0.7 71 95 80.6
Cu Concentrate 2.1 6.4 28.4 0.7 71 95 7.5
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Concentrate Grade Concentrate Recovery % Wt Sample Name Au, % Cu, % Mo, % Au Cu Mo g/t
Mo Concentrate 0.2 0.9 1.3 53.2 0.1 0.0 73.0
Primary P2
Bulk Cu - Mo Concentrate 1.48 5.0 29.3 0.7 60.0 91.4 65.1
Cu Concentrate 1.46 5.0 29.6 0.2 59.8 91.2 18.0
Mo Concentrate 0.02 0.9 4.4 41.5 0.1 0.2 47.2
These four locked cycle tests form the basis for the process design criteria for the Project. They represent the two mineralized material types and Year 1-10 in a conceptual mine plan based on the April 2012 resource estimate, which was developed for internal use. In all four tests copper and molybdenum concentrates were produced. The average copper recovery for Supergene material was 87% with an average copper grade of 34%. The average copper recovery for Primary material was higher at 93.5% with a copper concentrate grade of 29%. The average molybdenum recovery for Supergene material was 56% with an average molybdenum grade of 47%. The average molybdenum recovery for Primary material was similar at 57% with a molybdenum concentrate grade of 47%.
13.4.2 Locked Cycle Tests Comparisons Using Brine & Tap Water
Six locked cycle tests were performed on three samples representing Supergene, Primary, and a 1:1 Supergene and Primary mineralized material blend. In one set of tests, brine water was used in the roughers and tap water in the cleaners. The other set of tests used tap water in both stages of the test. Results are summarized in Table 13-5.
Table 13-5: Locked Cycle Tests on Composites Comparing Use of Brine Water and Tap Water in Roughers
Concentrate Recovery Weight Concentrate Grade Sample Name % % Au, g/t Cu, % Mo, % Au Cu Mo
Brine Water in Roughers & Tap Water in Cleaners
Supergene
Bulk Rougher Concentrate 17.22 0.56 4.15 0.07 72.3 91.9 89.2
Bulk Cu - Mo Concentrate 2.34 3.69 29.2 0.27 63.4 86.5 54.7
Primary
Bulk Rougher Concentrate 13.44 0.82 3.65 0.13 72.0 94.4 92.4
Bulk Cu - Mo Concentrate 1.4 7.35 33.9 0.69 64.9 91.2 52.7
Supergene + Primary
Bulk Rougher Concentrate 12.4 0.83 5.02 0.13 73.9 93.2 90.6
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Concentrate Recovery Weight Concentrate Grade Sample Name % % Au, g/t Cu, % Mo, % Au Cu Mo
Bulk Cu - Mo Concentrate 2.1 4.21 29.4 0.64 61.7 88.8 75.0
Tap Water in Roughers and Cleaners
Supergene
Bulk Rougher Concentrate 13.49 0.67 5.37 0.09 65.6 91.4 88.2
Bulk Cu - Mo Concentrate 1.82 4.13 38.6 0.41 51.5 86.4 53.9
Primary
Bulk Rougher Concentrate 10.26 1.1 5.25 0.18 74.0 95.3 92.9
Bulk Cu - Mo Concentrate 1.5 6.91 36.2 1.02 64.7 92.5 72.7
Supergene + Primary
Bulk Rougher Concentrate 11.8 0.9 5.53 0.14 78.5 93.0 91.0
Bulk Cu - Mo Concentrate 1.8 5.3 35.9 0.7 63.5 87.8 67.4
These tests show similar copper recovery whether using brine or tap water in the rougher circuit. One notable difference is that the mass pull in the bulk rougher circuit is higher when using brine by approximately 2% to 4% resulting in approximately 20% greater rougher concentrate production.
The results for molybdenum show a little more variance. For Supergene material, the molybdenum recovery is essentially the same independent of water quality. For Primary material the recovery for brine + tap water is significantly lower by about 20%, while for the blend of Supergene and Primary material, the molybdenum recovery is 8% higher in the case of brine and tap water.
In future study phases of the Project, further test work using brine water should be performed including molybdenum cleaner flotation, which was not included in these tests.
13.4.3 Variability Rougher Kinetic Tests
Rougher kinetic tests were performed on 15 Supergene samples and 25 Primary samples. The results are summarized in Table 13-6 and Table 13-7 and shown in Figure 13-1 to Figure 13-4.
Table 13-6: Variability Rougher Test – Supergene Molybdenum Copper Feed Copper Rougher Molybdenum Sample No. Rougher Grade % Recovery % Feed Grade % Recovery % 9320 1.27 96.8 0.018 79.3 9321 1.66 95.0 0.029 91.5 9322 2.12 97.1 0.026 84.4 9323 1.49 96.3 0.028 88.7
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Molybdenum Copper Feed Copper Rougher Molybdenum Sample No. Rougher Grade % Recovery % Feed Grade % Recovery % 9324 1.91 97.5 0.020 87.1 9325 1.21 95.8 0.018 76.6 9326 0.92 98.5 0.010 91.2 9327 1.54 92.1 0.037 93.7 9328 1.64 93.3 0.019 92.5 9329 0.57 93.2 0.010 83.6 9330 0.59 94.4 0.007 90.9 9331 0.92 96.7 0.008 88.7 9332 0.51 83.4 0.004 80.1 9333 0.56 91.6 0.006 80.6 9334 1.52 95.8 0.012 91.5
Average 1.20 94.5 0.017 86.7
Figure 13-1: Copper Recovery vs Copper Feed Grade, Roughers – Supergene (Plenge, 2012)
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Figure 13-2: Molybdenum Recovery vs Molybdenum Feed Grade, Roughers – Supergene (Plenge, 2012)
Table 13-7: Variability Rougher Tests – Primary Molybdenum Copper Feed Copper Rougher Molybdenum Sample No. Rougher Grade % Recovery % Feed Grade % Recovery % 9335 0.91 98.0 0.015 89.8 9336 0.47 97.7 0.013 90.6 9337 0.59 95.1 0.006 82.2 9338 0.44 96.2 0.018 93.0 9339 0.78 97.9 0.024 95.0 9340 0.60 97.9 0.021 94.7 9341 0.51 97.6 0.028 97.0 9342 0.63 99.0 0.011 94.9 9343 0.35 97.2 0.032 90.0 9344 0.50 98.2 0.023 94.1 9345 0.46 97.6 0.010 95.7 9346 0.48 98.8 0.013 97.3 9347 0.51 97.9 0.010 87.1 9348 0.62 98.8 0.013 88.9 9349 0.64 97.5 0.013 84.4
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Molybdenum Copper Feed Copper Rougher Molybdenum Sample No. Rougher Grade % Recovery % Feed Grade % Recovery % 9350 0.66 99.0 0.009 87.5 9351 0.43 95.2 0.013 96.9 9352 0.33 94.6 0.010 96.1 9353 0.42 94.9 0.012 96.6 9354 0.55 97.2 0.020 98.1 9355 0.32 95.9 0.017 95.1 9356 0.37 97.7 0.013 95.1 9357 0.31 97.6 0.013 96.2 9358 0.38 97.8 0.011 85.7 9359 0.38 97.7 0.009 84.0
Average 0.50 97.3 0.015 92.2
Figure 13-3: Copper Recovery vs Copper Feed Grade, Roughers – Primary (Plenge, 2012)
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Figure 13-4: Molybdenum Recovery vs Molybdenum Feed Grade, Roughers – Primary (Plenge, 2012)
The average copper recovery for the rougher variability tests for Supergene material was 94.5% and for Primary material was 97.3%. The average molybdenum recovery for the rougher variability tests for Supergene material was 86.7% and for Primary material was 92.2%. All of these tests used tap water and the results show good recovery for both copper and molybdenum in the rougher stage of flotation.
13.4.4 Variability Cleaner Tests
Cleaner variability tests were performed on 15 Supergene samples and 25 Primary samples. The results are summarized in Table 13-8 and Figures 13-5 and 13-6 (Supergene) and Table 13-9 and Figures 13-7 and 13-8 (Primary).
Table 13-8: Variability Cleaner Tests – Supergene Molybdenum Copper Feed Grade Copper Cleaner Molybdenum Sample No. Cleaner % Recovery % Feed Grade % Recovery % 9320 1.23 94.3 0.018 72.7
9321 1.58 92.1 0.029 90.3
9322 2.02 95.5 0.025 81.5
9323 1.37 94.0 0.027 87.0
9324 1.98 95.8 0.020 79.0
9325 1.17 93.7 0.017 53.4
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Molybdenum Copper Feed Grade Copper Cleaner Molybdenum Sample No. Cleaner % Recovery % Feed Grade % Recovery % 9326 0.89 97.2 0.009 84.6
9327 1.60 88.6 0.036 90.5
9328 1.67 89.7 0.019 89.5
9329 0.55 88.8 0.009 80.4
9330 0.61 83.7 0.008 57.4
9331 0.92 94.1 0.009 82.1
9332 0.52 75.2 0.004 66.3
9333 0.55 86.1 0.006 72.3
9334 1.59 93.0 0.013 83.0
Average 1.2 90.8 0.017 78.0
Figure 13-5: Copper Recovery vs Copper Feed Grade, Cleaners – Supergene (Plenge, 2012)
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Figure 13-6: Molybdenum Recovery vs Molybdenum Feed Grade, Cleaners – Supergene (Plenge, 2012)
Table 13-9: Variability Cleaner Tests – Primary Molybdenum Copper Feed Copper Cleaner Molybdenum Sample No. Cleaner Grade % Recovery % Feed Grade % Recovery % 9335 0.89 95.7 0.016 81.9
9336 0.45 87.3 0.015 89.8
9337 0.56 90.3 0.006 76.9
9338 0.43 93.0 0.018 87.0
9339 0.74 96.4 0.026 91.5
9340 0.67 96.3 0.020 93.2
9341 0.53 96.9 0.027 95.5
9342 0.60 98.3 0.011 92.3
9343 0.34 96.1 0.037 95.8
9344 0.48 96.3 0.024 89.8
9345 0.45 95.4 0.010 93.2
9346 0.46 97.7 0.013 93.1
9347 0.49 95.4 0.009 92.0
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9348 0.61 97.8 0.013 96.1
9349 0.64 95.9 0.012 96.5
9350 0.64 98.1 0.009 95.7
9351 0.42 89.8 0.014 75.5
9352 0.32 91.2 0.010 94.8
9353 0.40 91.3 0.012 95.5
9354 0.54 94.8 0.021 97.4
9355 0.32 89.5 0.018 82.1
9356 0.35 95.4 0.014 86.8
9357 0.31 95.2 0.015 90.1
9358 0.40 96.9 0.013 94.6
9359 96.5 0.009 90.4
Average 94.6 0.02 90.71
Figure 13-7: Copper Recovery vs Copper Feed Grade, Cleaners – Primary (Plenge, 2012)
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Figure 13-8: Molybdenum Recovery vs Molybdenum Feed Grade, Cleaners – Primary (Plenge, 2012)
The average copper recovery for the cleaner variability tests for Supergene material was 90.8% and for Primary material was 94.6%. The average molybdenum recovery for the cleaner variability tests for Supergene material was 78% and for Primary material was 90.7%. All of these tests used tap water and the results show good recovery for both copper and molybdenum in the bulk cleaner stage of flotation.
The equations from the cleaner copper recovery versus copper feed grade curves were used to determine copper recovery in the annual concentrate production schedule.
13.4.5 Batch Cleaner Tests Varying Water Combination (Tap and Pit Water)
A series of four batch cleaner tests were performed on two samples representing Supergene and Primary materials to compare the effects of a variation in water quality. The results are summarized in Table 13-10.
Table 13-10: Batch Cleaner Test Results at Different Water Quality Blends Copper Copper Copper Molybdenum Molybdenum Water Molybdenum Feed Rougher Cleaner Rougher Cleaner Type Feed Grade % Grade % Recovery % Recovery % Recovery % Recovery % Supergene
100% Tap 0.8 91.2 75.3 0.012 90.2 34.3 25% Pit + 0.83 91.2 53.5 0.014 86.1 20.8 75% Tap 50% Pit + 0.81 91.5 61.5 0.014 86.7 33.8 50% Tap 75% Pit + 0.8 91.1 63.9 0.014 84.3 42.9 50% Tap Average 0.81 91.3 63.6 0.014 86.8 79.3
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Copper Copper Copper Molybdenum Molybdenum Water Molybdenum Feed Rougher Cleaner Rougher Cleaner Type Feed Grade % Grade % Recovery % Recovery % Recovery % Recovery % Primary
100% Tap 0.57 95.5 76.8 0.021 92.4 29.8 25% Pit + 0.53 94.1 47.2 0.020 87.4 17.5 75% Tap 50% Pit + 0.54 94.4 56.7 0.019 89.2 28.4 50% Tap 75% Pit + 0.56 94.4 74.3 0.019 92.0 53.9 50% Tap Average 0.54 94.6 63.8 0.02 90.3 32.4
The copper rougher recovery for Supergene material averaged 91.3% and there was very little difference in rougher recovery at the different water compositions. The copper rougher recovery for Primary material averaged 94.6% and there was little difference in rougher recovery at the different water compositions; however, 100% tap water provided a slight improvement (1.1%) in copper recovery over other blends of water types. This confirms that the use of brine water (or pit water) in the rougher flotation stage does not have a significant impact on rougher flotation as was shown in the locked cycle tests previously discussed.
The molybdenum rougher recovery using tap water appears to be a little better than using pit water for the Supergene material but there was not a noticeable difference with Primary material.
Although rougher flotation has shown little affect due to the water type, the cleaner flotation recovery results were impacted by water type.
The parameters of the brine water used in the test work are summarized in Table 13-11.
Table 13-11: Summary of Brine Water Analyses Salar de Plumas Parameter Unit Pit Water Arizaro Verde pH pH 7.1 8.3 7.05 Conductivity uS/cm >200 000 17 420 241 700 TDS mg/l 255 500 10 700 317 596 Alkalinity mg/l 49 129 - Bicarbonate mg/l 59 158 - Calcium mg/l 2 510 169 1558 Magnesium mg/l 1 350 82 706 Chloride mg/l 153 000 6 120 184 600 Sulfate mg/l 3 900 310 Nitrate mg/l 600 30 Sodium mg/l 84 400 4 120 70 277 Potassium mg/l 3 030 77
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Ausenco recommends that more test work, including locked cycle tests using site brine water be conducted to investigate further the use of brine water and site pit water for all flotation processes. This could have a significant impact on capital by reducing the desalination water treatment requirements.
13.5 Sedimentation and Filtration Test Work
Sedimentation test work of copper concentrates and tailings from Supergene and Primary material locked cycle tests were conducted; the results are summarized in Table 13-12 and Table 13-13, respectively.
Table 13-12: Copper Concentrate Sedimentation Results
Settling Requirement Material Type % Underflow m2/(t/d)
Supergene S1 63 0.06
Supergene S2 63 0.04
Primary P1 51 0.10
Primary P2 54 0.06
Average 58 0.07
Table 13-13: Tailings Sedimentation Results
Settling Requirement Material Type % Underflow 2 m /(t/d)
Supergene S1 52 0.08
Supergene S2 54 0.05
Primary P1 50 0.06
Primary P2 50 0.08
Average 52 0.07
Filtration test work of copper concentrates from Supergene and Primary material locked cycle tests were conducted; the results are summarized in Table 13-14.
Table 13-14: Filtration Results for Locked Cycle Test Copper Concentrates
Filtering Rate Material Type % Solids Feed % Moisture m2/(t/h)
Supergene S1 50 7 1.12
60 8 0.95
Supergene S2 50 5 1.12
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Filtering Rate Material Type % Solids Feed % Moisture m2/(t/h)
60 5 0.81
Primary P1 51 7 1.11
62 7 0.95
Primary P2 51 8 1.68
62 11 1.35
Average 56 7 1.14
75th Percentile 1.18
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14 Mineral Resource Estimates
14.1 Introduction
The mineral resource estimate was prepared under the direction of Robert Sim and assisted by Bruce Davis. Estimates are generated, from three–dimensional (3D) block models bases on geostatistical applications using commercial mine planning software (MineSight® v7.50). The Project limits are based in the UTM coordinate system using a nominal block size of 25 x 25 x 15 m (L x W x H). The majority of drill holes in the main deposit area are vertically oriented with holes spaced on a nominal 150 m grid pattern. At the northern end of the deposit, the final 500 m has been tested with holes that are consistently inclined -70° east.
The resource estimate was generated using drill hole sample assay results and an interpretation of the geologic model which relates to the spatial distribution of copper, gold, and molybdenum. Interpolation characteristics were defined based on the geology, drill hole spacing, and geostatistical analysis of the data. The resources were classified by their proximity to the sample locations and are reported, as required by NI 43-101, according to the CIM standards on Mineral Resources and Mineral Reserves (November 2010).
14.2 Geologic Model, Domains, and Coding
The copper, gold, and molybdenum mineralization on the Taca Taca property is interpreted to be the result of deep-seated rhyodacitic porphyry intrusions. The majority of the rocks that host the Taca Taca deposit are granodioritic in composition, plus minor dacite, diabase, and rhyolite dykes. The deposit is overlain by a leach cap that ranges from 300 m thick in the south to about 150 m in the north. This is underlain by a locally irregular Supergene Zone which varies in thickness from non-existent to greater than 300 m in some parts of the deposit. In some areas, supergene-type mineralization is locally present at depths of greater than 700 m below surface. This variability in supergene thickness is attributed to deep-seated enrichment along fault structures. The Supergene Zone contains varying amounts of chalcocite and covellite. Beneath the Supergene Zone is the Primary Zone domain comprised of varying amounts of pyrite, chalcopyrite, bornite, and minor molybdenite.
A sub-vertical fault is interpreted from drilling on the western side of the deposit area. Generally oriented at 345°, this structure shows variable vertical displacement with approximately 160 m of apparent displacement in the south, but little to no movement in the north. Copper mineralization is present on both sides of the structure, but there appears to be some post-depositional movement along this fault.
The majority of the deposit is hosted within rocks of granitic or granodioritic composition. A series of sub-vertical late/post-mineral dykes occur to the east and southeast of the main deposit area. These dykes have been interpreted based on a combination of drilling results and surface mapping. Dykes of rhyodacitic composition are present primarily in the southeastern part of the deposit and tend to be post-mineral in nature. Several rhyolite dykes are interpreted in the eastern part of the deposit. These rhyolite dykes show mineral trends which suggest they were emplaced prior to or during the mineralizing event.
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Immediately east of the deposit area is a salt brine salar in which a series of drill holes were collared from the surface of the salt crust. The base of the salar was interpreted from the results of this drilling and was included as overburden in the model.
The geologic interpretation of the base of Overburden Zone, the Leach Cap Zone, and the Supergene Zone was generated using drilling information. Three-dimensional, wireframe shape domains were generated and represent the extents of these various mineral zones (MinZone). The MinZone domains are summarized in Table 14-1 and shown in Figure 14-1.
Table 14-1: MinZone Domains and Coding
Zone Code Domain Comment Number
Overburden (OVB) 1 Surface soil and gravel, plus the salar.
Leach (LX) 2 Average 300 mV near-surface zone leached of copper.
Supergene (SS) 3 Supergene zone of enriched copper.
Primary (PR) 4 Zone of primary sulphide mineralization.
5 Late/post mineral dykes. Rhyodacite Dykes (DK) Tend to be weakly mineralized or unmineralized.
6 Pre/syn mineral dykes. Tend to be mineralized similar Rhyolite Dykes (RDK) to surrounding host rocks.
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Figure 14-1: Isometric Views of MinZone Domains (Sim, 2013)
14.3 Available Data
Delineation and exploration drilling have been ongoing at the Project for several years. Lumina Copper delivered the final database on October 30, 2012 and it included information from 440 drill holes, with a cumulative length of 163,537 m. Drill holes occur over an area that measures 5 km x 5 km, with a few drill holes dating back to the 1970s.
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Comments relating to the sample database include the following:
Most of the holes drilled by Corriente Resources in the 1990s were designed to target near- surface veins and mantos, and, as a result, these do not provide information relating to the deeper-seated porphyry mineralization. There are 52 holes in the database that do not have any associated sample results. Seven of these were drilled by Lumina Copper for geotechnical purposes and none of those have been sampled or analyzed. The remaining 45 are older drill holes that were either never sampled or the assay data is missing. Lumina Copper drilled a total of 97 RC holes. Parts of the Leach Zone have been delineated using RC drilling. RC holes have been used primarily in testing the northern and northwestern mineralized areas where mineralization tends to occur to depths of only 300 m. Comparisons between samples from DD holes and RC holes show local variability, but good overall correlation for copper and molybdenum. Gold grades tend to be slightly higher in DD holes than RC holes, but the differences are not considered significant.
The mineral resource estimate is based on a total of 147,449 m of drilling in 310 drill holes that are proximal to the potentially economic mineralization. The associated assay data includes: BHP, 28 holes (9,893 m); Corriente Resources, 18 holes (1,454 m); Rio Tinto, 15 holes (7,608 m); and, Lumina Copper, 249 holes (128,494 m). The distribution of drilling is shown in Figure 14-2.
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Figure 14-2: Distribution of Copper Grades in Drill Holes (Sim, 2013)
The previous mineral resource estimate was generated in April 2012. Figure 14-3 shows the distribution of data that was available for the April 2012 resource estimate (shown in blue) compared to the additional sample data available for use in the current resource estimate (shown in red). Significant additional drilling has been completed north and northwest of the main deposit area. Deep drilling has begun to delineate what appears to be the eastern limit of the deposit. Additional holes in the central and southern parts of the deposit have significantly improved the understanding of the deep-seated mineralization in these areas.
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Figure 14-3: Distribution of Additional Sample Data since the April 2012 Resource Estimate (Sim, 2013)
The majority of the drill holes that test the deeper porphyry zone are variably spaced between 100 m and 200 m intervals. Initial drilling on the deposit consisted of holes that ranged from 400-600 m long. In 2008, Rio Tinto drilled hole TTBJ0002 to a final depth of 1,153.3 m; this remains the deepest hole on the property. Lumina Copper has intersected appreciable copper mineralization in numerous drill holes pushed to greater than 900 m below surface. The majority of drill holes that test the porphyry are vertically oriented with a few holes drilled at inclinations as shallow as -60°. Recent drill holes located in the northern part of the deposit area are inclined at -70° in an eastern direction to further evaluate a pervasive sub-vertical, north-south series of structures interpreted to be present.
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Downhole survey data only exists for holes drilled since 2008; data includes holes drilled by Rio Tinto and all holes drilled by Lumina Copper. Available survey data indicates that drill hole deviations are variable, but can be significant in some cases, especially in the upper leached rocks. It is safe to assume that similar degrees of deviation have occurred in previous drill holes. This is not considered overly significant in respect to a global resource estimate using the current drill hole spacing; however, this fact should be considered as the Project evolves. Some drill holes may have to be re-drilled to confirm the exact location of the contained sample data.
A total of 149,293 m of the drilling was sampled and analyzed for copper and, in most cases, a suite of other minor elements. There are 74,400 individual samples in the database that were tested for copper content, with an average sample length of 2 m. A total of 10 elements were incorporated into the resource model, many of which have no apparent economic influence on the Project. This report describes only the estimation of copper (Cu%), gold (Au g/t), and molybdenum (Mo%) in the resource model. A basic statistical summary of all of the primary sample data is listed in Table 14-2.
Table 14-2: Basic Summary of All Sample Data
Number of Total Standard Element Minimum Maximum Mean Samples Length (m) Deviation Copper (Cu%) 74,400 149,280 0 14.75 0.195 0.337 Molybdenum (Mo%) 73,872 148,229 0 1.000 0.009 0.015 Gold (Au g/t) 73,962 148,410 0 17.490 0.077 0.170
As stated previously, the Taca Taca drilling database includes holes that test for satellite exploration targets and near surface veins and mantos. Of the 440 drill holes in the database, 310 holes are within the immediate vicinity; these 310 holes have potential influence on the mineral resource estimate. A basic statistical summary of these proximal drill holes is listed in Table 14-3.
Table 14-3: Basic Summary of Sample Data Proximal to the Resource Model
Number of Total Standard Element Minimum Maximum Mean Samples Length (m) Deviation Copper (Cu%) 71,144 143,740 0 14.75 0.201 0.341 Molybdenum (Mo%) 70,591 143,625 0 1.000 0.010 0.015 Gold (Au g/t) 70,714 143,713 0 14.300 0.078 0.149
The geologic information is derived primarily from observations during logging, and includes lithology, alteration facies, and mineral zonation type.
14.4 Compositing
Drill hole samples are composited to standardize the database for further statistical evaluation. This step eliminates any effect sample lengths may have on the estimate.
To retain the original characteristics of the underlying data, a composite length that reflects the average original sample length is selected. The generation of longer composites results in some degree of smoothing which could mask some of the features of the data. Sample intervals range from 0.35-6 m long, with an average of 2 m. As a result, a standard 2 m composite length was generated for statistical evaluation and for use in grade estimations in the block model.
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Drill hole composites are length-weighted and were generated “down-the-hole”, this means composites begin at the top of each hole and are generated at 2 m intervals down the length of the hole. The contacts of the MinZone domains, listed in Table 14-1, were honoured during compositing of drill holes. Several holes were randomly selected and the composited values were checked for accuracy. No errors were found. Logged lithology, alteration, and MinZone data were assigned to composited intervals on a majority basis to allow for statistical analysis of these variables.
14.5 Exploratory Data Analysis
Exploratory data analysis (EDA) involves statistically summarizing the database to quantify the characteristics of the data. One of the main purposes of EDA is to determine if there is any evidence of spatial distinctions in grade; this would require the separation and isolation of domains during interpolation. The application of separate domains prevents unwanted mixing of data during interpolation; this will result in a grade model that better reflects the unique properties of the deposit. However, applying domain boundaries in areas where the data is not statistically unique may impose a bias in the distribution of grades in the model.
A domain boundary segregating the data during interpolation is typically applied if the average grade in one domain is significantly different from that of another domain. A boundary may also be applied where there is a significant change in the grade distribution across the contact.
14.5.1 Basic Statistics by Domain
The basic statistics for the distribution of copper, gold, and molybdenum were generated by lithology type, alteration facies type, and by interpreted MinZone type. The drill core logs have identified 13 different rock types; 86% are comprised of granite. Although some other rock types may suggest distinct metal properties, they tend to be so rare that it is not practical to use them for resource estimation purposes. The late stage rhyodacite dykes show relatively low copper grades compared to the rhyolite dykes that average 0.30% contained copper.
Comparison of alteration types show propylitic alteration tends to be lower in copper, gold, and molybdenum. This alteration type is present in only a few drill holes that tend to occur around the perimeter of the main deposit area.
The interpreted MinZone domains show copper grades to be highest in the Supergene Zone and lowest in the Leach Zone domain (Figure 14-4). The difference between the two types of dykes is quite evident: the rhyolite dyke grades are similar to the Supergene and Primary Zones, and the rhyodacite dykes show relatively low copper content. There are no significant differences in gold and molybdenum content in relation to the MinZone types.
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Figure 14-4: Box Plot Copper by MinZone Domain
14.5.2 Contact Profiles
The nature of grade trends between two domains is evaluated using the contact profile; this profile graphically displays the average grades at increasing distances from the contact boundary. A contact profile that shows a marked difference in grade across a domain boundary is an indication that the two data sets should be isolated during interpolation. Conversely, if there is a more gradual change in grade across a contact, the introduction of a hard boundary (in other words, segregation during interpolation) may result in much different trends in the grade model. In this case, the change in grade between domains in the model is often more abrupt than the trends seen in the raw data. Finally, a flat contact profile indicates no grade changes across the boundary. In the case of a flat profile, hard or soft domain boundaries will produce similar results in the model.
Contact profiles were generated for copper grades between the interpreted MinZone domains. Distinct changes in grade are evident between all MinZones at the domain boundaries. The profiles for the Leach Zone-Supergene Zone (LX-SS) and Supergene Zone-Primary Zone (SS-PR) contacts are shown in Figure 14-5 and Figure 14-6. The results suggest that these boundaries were honoured during the generation of the copper resource model. The rhyolite dyke does not show any significant grade change with the surrounding host rocks.
The nature of molybdenum and gold across domain boundaries was also reviewed and no significant trends or changes were identified.
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Figure 14-5: Contact Profiles Copper between LX and SS MinZones
Figure 14-6: Contact Profiles Copper between SS and PR MinZones
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14.5.3 Conclusions and Modeling Implications
Boxplots show that differences exist in copper grades between the various MinZone domains, and this is further supported by the contact profile analysis. Late-stage rhyodacite dykes, containing lower copper grades, were interpreted using surface mapping and drill core logging information. All of these domains should be recognized and honoured with hard boundary conditions during block estimations of copper content in the resource model.
The rhyolite dykes show similar mineral content as their surrounding host rocks and, as a result, this unit does not require segregation during block grade interpolation. The areas identified as rhyolite dykes were included within the corresponding Leach, Supergene, or Primary MinZone domains.
There do not appear to be any significant differences in the distribution of gold or molybdenum in relation to any of the geologic domains present in the deposit. As a result, there are no restrictions during block grade interpolations of these elements.
The interpolation domains are summarized in Table 14-4.
Table 14-4: Summary of Interpolation Domains
Zone Code Domain Comments Number 1 OVB (Overburden Zone) – no estimates conducted 2 LX (Leach Zone) -- hard boundary Copper 3 SS (Supergene Zone) – hard boundary 4 PR (Primary Zone) – hard boundary 5 Rhyodacite Dyke – hard boundary Molybdenum 2-5 Combined all domains (excl. OVB) Gold 2-5 Combined all domains (excl. OVB)
14.6 Bulk Density Data
During the 2011-2012 drilling program, samples were sent to ALS Chemex in Lima, Peru for bulk density measurements. To date, 662 samples were selected on approximately 100 m intervals from drill holes spread throughout the deposit area.
Bulk density was measured using the wet method: paraffin wax-coated pieces of core, averaging 10 cm to 15 cm in length, are weighed in air and then again while submerged in water. The following formula for specific gravity was used: