Mining World Russia Complete Refractory Gold Solutions 10 April 2014

1. Introduction to BIOMIN 2. BIOX ® Technology 3. ASTER™ Technology 4. HiTeCC Technology 5. Conclusions Contents 2

Introduction to BIOMIN

BIOMIN is a South African based company focused on the delivery of premier, relevant solutions for the effective processing of refractory gold ores Three fully commercialized technologies: 1. The BIOX ® Process for the treatment of refractory gold ores 2. The ASTER™ Process for the treatment of cyanide and thiocyanate contaminated solutions 3. The HiTeCC Process for the treatment of preg-robbing and double refractory ores Introduction to BIOMIN 4

The BIOX ® Process

Late 1970’s – Research initiated at Gencor’s Laboratories 1986 – Fairview 10 tpd pilot plant 1990 – Harbour Lights: First BIOX ® licence sold 1994 – Ashanti BIOX ® plant : 720 tpd BIOX ® Plant (Expanded to 960 tpd in 1995) 2005 – 2 nd generation BIOX ® plants 2005 – Suzdal BIOX ® plant, Sub-zero application of the technology 2010 – Kokpatas BIOX ® plant: 2,138 tpd concentrate 2013 – 3 rd / 4 th Generation BIOX ® Design – Runruno BIOX ® Plant The BIOX ® Process is owned by BIOMIN South Africa, through its wholly owned subsidiary Biomin Technologies SA BRIEF TECHNOLOGY HISTORY 6

Current and Historical BIOX ® Operations 7 Mine Year Commissioned Capacity (tpd Conc) Status Generation I BIOX ® Plants Fairview, South Africa198662Operating Saõ Bento, Brazil Care and Maintenance Harbour Lights, Australia199140Decommissioned Wiluna, Australia Care and Maintenance Ashanti, Ghana Operating Coricancha, Peru199860Care and Maintenance Generation II BIOX ® Plants Fosterville, Australia Operating Suzdal, Kazakhstan Operating Bogoso, Ghana Operating Jinfeng, China Operating Kokpatas, Uzbekistan Operating Agnes, South Africa201020Care and Maintenance

BIOX ® GEN III & GEN IV 8 BIOX ® GI, GII BIOX ® GIIIBIOX ® GIV Current BIOX ® DesignEase of Operation and Maintainability 10 % Reduction in Capex & Opex BIOX ® design is sound Established testing, design and commissioning procedures Increased robustness of BIOX ® design Improved BIOX ® service offering Improved knowledge transfer Process improvements Major capex items: Tanks Agitators Blowers Major opex items: Power Reagents Factors affection BIOX ® performance: Mechanical failures Maintenance issues Process control Attend to major problem areas: Mechanical reliability Ore variability Process losses Improved agitator system Materials of construction High temperature bugs /32013/4 Refining a World Class Technology

Generation III Design Development 9 Improved Robustness Improved Process Design Improved Service Offering / Engagement Improved Knowledge Transfer

1. Project owner:Metals Exploration 2. Project location:Philippines 3. Continuous BIOX ® Pilot plant test conducted in Construction decision on 1 July Commissioning planned for Q Both BIOX ® and ASTER™ Technologies RUNRUNO Project Implementation 10

1. Improved engagement between all role-players:  Owners team  Project team  Equipment manufacturers  BIOMIN project team 2. Structured Knowledge Transfer and Training  Target decision makers from start of design process  Knowledge transfer strategy: – From design phase through to commissioning and operation – Project specific BIOMIN training material  Post commissioning engagement: – Structured audits and process optimisation – Continuous feedback on process performance and optimisation Key Features – GEN III 11

Robust Design taking into consideration 1. Ore variability and consistency of supply over life of mine  Sufficient surge capacity  BIOX ® configuration and equipment selection  Flexibility built into the design 2. Mechanical reliability  BIOMIN best practices guidelines  Finite Element Analyses on tank, super structure and agitator shaft and gearbox  Third party compliance review 3. On-site metallurgical laboratory  Continuous mill, float and BIOX ® pilot plants  Variability testing of new ore zones  Process optimisation Key Features – GEN III 12

Schematic of RUNRUNO Plant 13

IBC Container 14

IBC Container 15

THE ASTER™ PROCESS

The ASTER™ Process 17 Biological Process For Cyanide and Thiocyanate Destruction  Alternative Process To Inco/SO 2, Caro’s Acid and Alkaline Chlorination (Chemical)  Exotic, expensive reagents (Sodium meta-bisulphate, H 2 SO 5, hypochlorite (OCl / Cl 2 )  ASTER Allows  Effective water management by treating CIL/CIP residual solutions and recycling upstream  Environmentally compliant tailings disposal  ASTER Advantages  Low capital and operating cost  Safe, fertilizer type nutrients - no exotic additives  Degradation of SCN, CN, WAD CN  Commercially proven technology 2 ND INDUSTRY DELIVERY (KAZAKHSTAN) rd & 4 TH INDUSTRY DELIVERY (PHILIPPINES) 2014/5 *Ultimate Delivery: Cyanide detoxification of any tailings stream VALIDATION 1 ST INDUSTRY DELIVERY (SOUTH AFRICA) DEVELOPMENT

COMMERCIALISATION 18 Barberton Mines, Consort Plant  Location:Barberton, South Africa  Commissioned:2010  Capacity:320 m 3 /d  Feed:  CN - 30 mg/l  SCN mg/l  Effluent:< 0.1 ppm SCN - & CN -

COMMERCIALISATION 19 NordGold, Suzdal Plant  Location:Semi, Kazakhstan  Commissioned:2013  Capacity:500 m 3 /d  Feed:  CN - 30 mg/l  SCN - 1,200 mg/l  Effluent:< 0.1 ppm SCN - & CN -

The HiTeCC Process

HiTeCC Process 21 High Temperature Caustic Conditioning  Double Refractory Ores  Dissolved gold adsorbs onto finely disseminated carbon  Activated carbon reverses adsorption if preg robbing weak  In severe cases, large metal losses occur  Use of blinding agents partially successful – immiscible and difficult to control  HiTeCC Allows  Effective desorption of preg robbed gold from NCC  Adsorption dissolved gold onto fresh carbon  Process trialled, implemented successfully 2 ND INDUSTRY DELIVERY (KAZAKHSTAN) rd INDUSTRY DELIVERY 2015/6 1 ST INDUSTRY DELIVERY (FOSTERVILLE GOLD MINE) DEVELOPMENT AT FOSTERVILLE GOLD MINE

Fosterville HiTeCC Implementation 22  Location:Bendigo, Australia  Commissioned:2010  Capacity:400 tpd Combined fresh CIL tails & reclaimed tailings  Recovery:> 10 % Additional recovery attributable to use of HiTeCC circuit

HiTeCC Process 23 ClientIncrease (%)Recoverable Au (g/t) Opex (g/t) Fosterville Kazakhstan840.7 Project Project Project 3Testwork In Progress Typical Additional Gold Recoveries Through HiTeCC

Conclusions

 Fewer oxide deposits available and increased focus on Refractory Gold deposits  Refractory ores often associated with complex mineralogy:  Presence of organic carbon  Presence of base metals and heavy metals  Variability in ore feed rate and characteristics  Cost effective environmentally friendly solutions required to treat these ore bodies:  Effective water management  Stable products safe for land disposal  Robust technology, suited to remote locations Conclusions 25

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