Magnetite potential of the Upper Zone of the Bushveld Complex in the Northern Limb. Limpopo Minerals Conference 12 November 2015.

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1 RESOURCES LTD Magnetite potential of the Upper Zone of the Bushveld Complex in the Northern Limb Limpopo Minerals Conference 12 November 2015 Dr Luke Longridge

2 The Upper Zone on the Northern Limb

3 The Upper Zone on the Northern Limb

4 The Upper Zone on the Northern Limb From Ashwalet al. (2005)

5 The Upper Zone on the Northern Limb Magnetite Layer From m To m Width m V ppm V2O5% TiO2% Fe2O3% TiO2 / V2O5 Ratio Fe2O3 / V2O5 Ratio Fe2O3 / TiO2 Ratio V2O5 / Fe2O3 Ratio x100 TiO2 / Fe2O3 Ratio x100 R Q* P O N M L K J I II** H G F E D C B A * Includes 2.40m core loss ** Logged as Magnetite Leucogabbro

6 Key Features of Magnetite Layers Sharp lower contact, gradational upper contact 6

7 Key Features of Magnetite Layers Composite Magnetite Layers MML & HW Layers

8 Key Features of Magnetites Stringer-type magnetite of massive magnetite bands with barren anorthosite material common in the P-Q

9 Xenoliths Key Features of Magnetites

10 Phosphate

11 Phosphate Appearance of apatite immediately above the P-Q Magnetite 11

12 Phosphate Appearance of apatite immediately above the P-Q Magnetite

13 Economic Potential Strike identified based on coincident geochemistry and airborne magnetics data interpretation Total strike length potential identified to be >20km MML: 52 Mt resource P-Q Zone: 939 Mt resource defined thus far on ~ 40% of strike Up to 13 km additional strike extensions 13

14 Economic Potential ~1 Bn tonnes per 10 km of strike extent (using the Bushveld Minerals project on the Northern Limb as an example) Over 350 km of strike potential for this same layer, identified in the Western and Eastern Limbs of the Complex So Potential for >35 Bn tonnes of resources on the Complex Also Phosphate, Vanadium, Titanium

15 Phosphate Concentrate P-Q Zone Concentrate MML Concentrate 36-39% P 2 O 5 ~55% Fe, 18-19% TiO 2, % V 2 O 5 ~56% Fe, 12% TiO 2, 2% V 2 O Flotation Magnetic Separation Magnetic Separation Phosphate Zone (Indicated & Inferred 0-400m): P-Q Zone (Indicated & Inferred 0-400m): MML (Indicated 0-120m): % P 2 O % Fe, 10.7% TiO 2, & 0.2% V 2 O % Fe, 9.7% TiO 2,1.48% V 2 O 5

16 PQ Metallurgy - Concept ~20-50% Fe, 5-15% TiO 2, 0.1-2% V 2 O 5, upgraded through magnetic separation to ~55-57% Fe, with TiO 2, V 2 O 5 Value in Fe, in TiO 2 & V 2 O 5 Requires beneficiation more difficult, potentially more profitable Ti-slag (30-35% TiO 2 ) Concentrate Kiln DRI Furnace Hot Metal If ore has high vanadium (i.e. MML), can extract Fe and V 2 O 5 though smelting and vanadium ladle. Create value for Fe and V, Ti-slag may be amenable to further treatment to create a Ti product Ladle Ti-slag (30-35% TiO 2 ) Sulphate Leach TiO 2 Pig Iron Vanadium Slag Product 16

17 PQ Metallurgy - Concept For High-Ti, lower V ores, the challenge is to create value from both Fe and Ti Ti-slag (>60% TiO 2 ) Concentrate KILN DRI Furnace Hot Metal/Pig Iron This is WITHOUT flux need to use little or no flux to ensure high Ti grades in the slag But this creates problems for the slag and furnace a corrosive, sticky slag 17

18 PQ creating value from Ti-magnetite Alternatively, is there a way to separate the Fe from the Ti WITHOUT smelting? Pre-reduction tests on Bushveld Minerals P-Q Magnetite concentrate (-45 µm) Direct reduction to high degree of metallization with coarsening of metallic iron. Rotary kilns are not suitable ringing from molten/liquid iron droplets Use a Rotary Hearth Furnace (RHF) 18

19 PQ Direct Reduction (RHF) Concentrate Rotary Hearth Furnace DRI Crushing/Milling and Magnetic Separation Metallised Iron Ti-slag (60% TiO 2 ) 19

20 PQ Phosphate Zone -Metallurgy Phosphate is in the form of Apatite Ca 5 (PO 4 ) 3 (F,Cl,OH), which can be separated into a clean concentrate Concentrate production through flotation has been demonstrated at SGS Currently busy with a scoping study evaluating P 2 O 5 concentrate production from this zone 20

21 Bushveld Vanadium Project Mineral Processing Roast Processing Route Chosen Illustrative flow-sheet for Salt Roast process Concentration Salt Roasting Leach Milling & Purification AMV precipitation a) Simple flow sheet, b) Relatively low capex (~US$261m for 10,350 tonne V 2 O 5 production capacity) c) Iron-rich calcine (~54%Fe, ~11% TiO 2 ) could be monetised De-ammoniation and fusion Flaking 21

22 Bushveld Vanadium Project Processing Flowsheet Preferred Processing Route Salt Roast Currently operating mines are processing similar types of ore to that of Bushveld s and probable processing routes have been identified: Rhovan Ferrovanadium Plant (Glencore) Salt Recovery Plant Ore preparation Salt Roast Rotary Kiln Leaching Purification AMV Source: Google earth Satellite imagery of Rhovan (Glencore) vanadium plant

23 Thank you! 23

24 Models for Magnetite Formation Magma chamber replenishment (may be replenishment, but very few An# reversals associated with magnetite layers in the upper zone). 24

25 Models for Magnetite Formation fo 2 changes during fractional crystallisation (emplacement of a H 2 O-rich magma) 25

26 Models for Magnetite Formation Pressure changes in magma chamber Similar effect to change in fo 2, do not expect a change in An# 26

27 Models for Magnetite Formation Immiscible liquids 27

28 Models for Magnetite Formation Basal boundary layer crystallisation 28