NI 43-101 Technical Report for the San Gregorio Project, Minas de Corrales, Rivera, Uruguay. Prepared for: Orosur Mining Inc. Prepared by: Randall Corbett, P.Eng. B Eng (Mining) General Manager San Gregorio Project – OMI Inc. William Lindqvist, MAusIMM, SEG and AIME PhD Applied Geology Non- Executive Director – OMI Inc. John Barber, PE Principal Mining Engineer AMEC E&C Services Inc. Effective Date: 22nd October, 2010 0 CONTENTS 1 SUMMARY ................................................................................................................ 1-1 1.1 Location and Access .......................................................................................... 1-1 1.2 Climate and Physiography ................................................................................. 1-1 1.3 Local Resources................................................................................................. 1-1 1.4 Mineral Tenure, Surface Rights, and Royalties.................................................. 1-2 1.5 Permits ............................................................................................................... 1-2 1.6 Environmental .................................................................................................... 1-2 1.7 Geology and Mineralization................................................................................ 1-3 1.8 Exploration ......................................................................................................... 1-3 1.9 Drilling ................................................................................................................ 1-3 1.10 Sample Preparation and Analysis ...................................................................... 1-3 1.11 Data Verification................................................................................................. 1-4 1.12 Metallurgical Testwork........................................................................................ 1-4 1.13 Mineral Resources ............................................................................................. 1-5 1.14 Mineral Reserves ............................................................................................... 1-5 1.15 Mining Operations .............................................................................................. 1-9 1.15.1 Open Pit Mining Operations........................................................................ 1-9 1.15.2 Planned Underground Operation ................................................................ 1-9 1.15.3 Sequencing ............................................................................................... 1-10 1.16 Process ............................................................................................................ 1-11 1.17 Tailings............................................................................................................. 1-11 1.18 Capital and Operating Costs ............................................................................ 1-12 1.19 Markets............................................................................................................. 1-13 1.20 Financial Analysis............................................................................................. 1-13 2 INTRODUCTION....................................................................................................... 2-1 2.1 Qualified Persons............................................................................................... 2-1 2.2 Effective Dates ................................................................................................... 2-1 2.3 Previous Technical Reports ............................................................................... 2-2 3 RELIANCE ON OTHER EXPERTS........................................................................... 3-1 4 PROPERTY DESCRIPTION AND LOCATION ......................................................... 4-1 4.1 Location and property boundaries...................................................................... 4-1 4.2 Property and Title in Uruguay............................................................................. 4-1 4.2.1 Mineral Title................................................................................................. 4-1 4.2.2 Royalties ..................................................................................................... 4-2 4.2.3 Surface Rights............................................................................................. 4-2 I 4.2.4 Water Rights ............................................................................................... 4-2 4.2.5 Environment................................................................................................ 4-3 4.3 Area of the property............................................................................................ 4-3 4.4 Mineral Tenure ................................................................................................... 4-3 4.4.1 Tenure History............................................................................................. 4-3 4.4.2 Mineral Title................................................................................................. 4-4 4.5 Surface Rights.................................................................................................. 4-10 4.6 Royalties........................................................................................................... 4-16 4.7 Sectorial Permits .............................................................................................. 4-17 4.8 Environmental Permits ..................................................................................... 4-18 4.9 Environmental liabilities.................................................................................... 4-20 4.9.1 Baseline Studies ....................................................................................... 4-21 4.9.2 Remediation and Closure.......................................................................... 4-24 5 ACCESSIBILITY, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE AND PHYSIOGRAPHY............................................................................................................. 5-1 5.1 Accessibility........................................................................................................ 5-1 5.2 Climate ............................................................................................................... 5-1 5.3 Local Resources and Infrastructure ................................................................... 5-2 5.4 Physiography, Flora and Fauna ......................................................................... 5-3 6 HISTORY................................................................................................................... 6-1 7 GEOLOGICAL SETTING .......................................................................................... 7-1 7.1 Project Geology.................................................................................................. 7-4 7.2 Deposits ............................................................................................................. 7-4 7.2.1 Santa Teresa............................................................................................... 7-4 7.2.2 Veta A and Veta Sur ................................................................................... 7-4 7.2.3 San Gregorio............................................................................................... 7-5 7.2.4 Ombú .......................................................................................................... 7-6 7.2.5 Arenal.......................................................................................................... 7-7 7.2.6 Castrillon ..................................................................................................... 7-8 7.2.7 Sobresaliente ............................................................................................ 7-10 7.2.8 Zapucay, Knob Hill, and Argentinita.......................................................... 7-11 7.2.9 Crucera ..................................................................................................... 7-13 7.2.10 Picaflor ...................................................................................................... 7-14 7.3 Prospects and Targets ..................................................................................... 7-15 7.3.1 Nueva Australia......................................................................................... 7-16 7.3.2 Peru........................................................................................................... 7-17 7.3.3 Areicua and Laureles ................................................................................ 7-17 II 7.3.4 Vaca Muerta.............................................................................................. 7-17 8 DEPOSIT TYPES...................................................................................................... 8-1 8.1 Comment on Section 8....................................................................................... 8-1 9 MINERALIZATION .................................................................................................... 9-1 9.1 San Gregorio...................................................................................................... 9-1 9.2 Santa Teresa.....................................................................................................