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Martin Moloney Principal Geologist – New Commodities Grassroots nickel sulphide exploration in the western Gawler Craton, South Australia South Australian Exploration and Mining Conference 2 nd December 2016

New Commodities - Fowler - SAEMC Dec 2 2016

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Page 1: New Commodities - Fowler - SAEMC Dec 2 2016

Martin Moloney Principal Geologist – New Commodities

Grassroots nickel sulphide exploration in the western Gawler Craton, South Australia South Australian Exploration and Mining Conference 2nd December 2016

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Target overview: Greenfields magmatic Ni-Cu-Co-PGE sulphides Pipeline Stage: Prospect-scale Target Identification Ownership: Iluka Resources 100%

Summary:

• Tenement package around Jacinth HM deposit ~ 22,500 sq. km • Province-scale NiS grassroots campaign undertaken by Iluka • Results validate generative concept • Substantial remaining prospectivity

Overview

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Regional Geology

• Archean margin • Inverted rift structure • Broad gravity high - 200km x 60km

(onshore) • Voluminous Paleoproterozoic mafic

intrusive rocks • Amphibolite – Granulite facies met. • Steep dips • Outcrop < 1% - cover 0-100m • Residual profile

PIRSA Mesa Journal 39 2005

Iluka 100% Tenure (Nov. 2016)

AOI

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Multidisciplinary Exploration Campaign

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Summary of Exploration Methods

Regional-Scale Prospect-Scale

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Magnetics

150,000 line km, 100m spacing, low-level acquisition

Mag RTP – linear stretch

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Data Acquisition - pXRF

Iluka’s library of AC drilling samples: • 000’s drillholes • ~30% intersected basement • initial geochemical evaluation via pXRF

analysis

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Magnetics & pXRF

Cluster of anomalous chalcophile results from

pXRF

Woodford

Mag RTP – linear stretch

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Ground Gravity

5,773 stations acquired at nominal 1,000m / 400m spacing

400m infill

Yalata license not yet completed

Bouguer Residual

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Airborne & Ground EM

VTEM: 5169.8 line km 35% effective to moderate depths 250 anomalies detected 8 high priority / 52 moderate priority

Ground EM coverage

Conductive cover remains challenging for airborne EM Stratigraphic conductors in Proterozoic absent

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VTEM reveals probable impact crater

VTEM Gravity Res.

Mag RTP Topography

Conductive sediment filled depression (2km wide, ~225m thick) Resistive crater rim (5km diameter)

Wolf Creek

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Geological Synthesis

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Target / AC drilling summary Magnetics imagery with gravity anomalies

RTP Magnetics Imagery with Gravity Anomalies

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Emphasis on data synthesis esp. in the field

Critical to vector toward the base of each intrusion to prioritise infill

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Woodford Drill Section

Sulphidic

metasediment

Gabbros

Hornfelsed

metagranite

Gravity 1VD Profile

188AC (eastern margin):

Mineral layering at ~50° to

long core angle = dip of

syncline limb

• AC defines

Syncline structure

• Ultramafic base

exposed on

eastern margin

V/H = 10

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MLEM

Limit of MLTEM effectiveness (approx. 500 m)

Upper mafic zone

Lower ultramafic zone

Woodford Intrusion

Woodford Simplified Interp Section

Residual Profile

Cover

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Mapping Intrusive Structure – Targeting EM

• Pyroxenites (182AC / 188AC)

expressed as mag low on

eastern margin of syncline

• Integrating magnetics with AC

results defines search space

for basal nickel sulphides

Layered

Gabbro

RTP Residual Magnetics Imagery

Ground EM Survey Plan

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AC Geochemical Ranking 1 Compatible immobile trace element variations in AC samples by Prospect

High levels exposed

Lower levels exposed

9 8 14 2 2 6 2 3 5 6 13 3 5 1 7 1 1 5 3 16

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9 8 14 2 2 6 2 3 5 6 13 3 5 1 7 1 1 5 3 16

AC Geochemical Ranking 2 Chalcophile trace element variations in AC samples by Prospect

188AC 85.5m Pyrite & millerite FOV = 1mm

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AC Chalcophile Elements Map

~30% of intrusions tested with AC have evidence of magmatic sulphide Substantial scope for further exploration

“Tested” by systematic ground EM

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Ground EM Defines Drilling Targets

F1_6

Ground EM provides highly specific drill targets Follow-up assessed / prioritised in terms of size and strength (conductance)

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Drilling Targets from Ground EM

TARGET EAST NORTH RL DIP AZIMUTH EOH Area TARGET DEPTH

F1_6 305070 6603335 213 60 270 200-250 70m x 130m 125-200 F1_5 294070 6594500 162 75 140 300 75m x 400m 150-250 Y1_2 344000 6496675 111 65 320 350-375 400m x 200m 250-350 F1_7 STH 303550 6593825 160 80 315 200 250m x 350m 100-150 F1_7 NTH 303420 6594480 169 60 315 200 500m x 750m 100-150

• VTEM surveying / ground EM follow-up defined 5 legitimate bedrock conductors

• PACE Funding approved for co-funding of DD for F1_5, F1_6 & F1_7 targets

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1. Essential elements for Ni mineral system present at regional – camp scale

2. Gravity / magnetics essential in directing exploration toward mafic / ultramafic intrusions

3. AC drilling at 200m spacing provides vectors toward potential trap sites within intrusions and

helps rank intrusions

4. VTEM surveying effective to a depth of ~200m over ~35% of area flown

5. Systematic EM surveying can screen prospective intrusions prior to follow-up drilling

6. Several intrusions have magmatic Cu-Ni sulphides (petrographic & geochemical evidence)

7. Many untested intrusions remain in the region

Summary

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Substantial prospectivity remains within the Project area:

1. Untested mafic intrusion targets in Northern Zone (defined by detailed gravity)

2. Various Ground EM and VTEM targets

3. Southern half of belt / tenure not tested (around Yalata)

4. Ooldea Gravity High

Fowler Domain Prospectivity

Iluka is considering the best way to take the project forward

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Iluka Resources Limited www.iluka.com

For more information, contact: Martin Moloney, Principal Geologist – New Commodities [email protected] +61 8 9360 4677 / +61 (0) 477 369 934