Aureus Mining New Liberty Project Geology February 2014
Contents • Location and Regional context • Deposit geology • Resources and Reserves • Grade Control • Underground potential • Near-mine exploration potential 2
New Liberty: Established Infrastructure Tarmac Road from Monrovia to Sierra Leone • Daily European flights • Three operating deep water ports • New Liberty is 100km from the deep-water commercial port at the capital, Monrovia • Tarmac road from port of Monrovia to within 20km of site, laterite road the final 20km to site 3
Location Map and License Areas New Liberty 4
Exploration Opportunities: 1,470km 2 Licence Portfolio New Liberty 5
New Liberty: Project History 6
New Liberty: Infrastructure Layout 7
New Liberty Exploration Camp and Pit Outline 8
Simplified Geology Showing Mineralisation Section 17 Section 25 9
New Liberty: Sections Showing Mineralisation Zones and Grades K347 K342 K343 K492 K433 21m @ 3.86g/t 28m @ 4m @ 1.28g/t 3.32g/t 16m @ 4.43g/t 9m @ 7.29g/t 10
New Liberty: Relationship Between Alteration & Gold Mineralisation Mineralised zone Pit outline (red) Magnetic depletion (grey) 11
Host rock and Alteration Margin Signatures Gold associated with Margins of Phlogopite low: mica, Magnesium, Potassium, Sodium, • Magnetic Rubidium susceptibility • Sodium • Potassium • Rubidium and high: • silicification • Sulphur • Arsenic • Tungsten 12
Mineralogy • Lower amphibolite grade (Tremolite-actinolite-hornblende-chlorite- phlogopite) assemblages • Pyrrhotite-arsenopyrite-gersdorffite • Gold associated with silicates and sulphides • Two gold populations: Coarse >10µm & Fine <10µm Gold with pyrrhotite (PO), chalcopyrite (CP) and non-opaque minerals (NOP) Interstitial fine gold between silicate minerals 13
Evidence of Shearing Above left: Breccias are common in the ultramafic unit, representing zones of shortening Left: Sheared clasts & mylonite in ultramafics Below: Highly sheared magnetite blebs in the ultramafic unit 14 14
New Liberty: Oblique View Showing Mineralisation and Pit Outline West Exploration camp West East East 15
New Liberty: Sections Showing Mineralisation Zones and Grades Section 25 Section 17 16
New Liberty: Resource and Reserves Larjor Latiff Kinjor Marvoe 2km West East 500m Underground Potential Footwall Zone • Resource increased to: – Measured: 651,000t at 4.8 g/t (for 100,000 ounces) 1 – Indicated: 9,145,000t at 3.6 g/t (for 1,043,000 ounces) 1 Au g/t – Inferred: 5,730,000t at 3.2 g/t (for 593,000 ounces) 1 0 – 0.8 0.8 – 2.0 – Total M & I: 1,143koz at 3.63g/t ; 2.0 – 4.0 Reserve Gold > 4.0 Tonnes Gold (koz) Classification (g/t) Proven 700,000 4.4 99 Probable 7,800,000 3.3 825 1 Cut off grade = 1.0 g/t Total Reserve 2 8,500,000 3.4 924 2 Cut off grade = 0.8 g/t 17 Note 1: Reserve reported at a cut-off grade of 0.8g/t Au and ore grading between 0.8 & 1.0 g/t cut-off is stockpiled for processing towards the end of the mine life Note 2: A dilution skin of 0.5m added and minimum mining width of 2.5m applied Note 3: A gold price of US$ 1,300 was used for pit optimisation
Grade Control Aim • Define mineralisation boundaries and minimise dilution • Define mining blocks Prior to mining • RC drill programme on 15x15m grid planned • Drill 1 year’s production in advance, ~ 8,000m/ year • Reconcile with orebody block model (based on a 30x30m grid) • Establish detailed distribution of gold and incorporate into mine planning 18
Grade Control Production • RC drilling in dry season advance of mining • Sample blastholes (10m benches) • In pit geological mapping – structures, bleaching, silicification, sulphides, mag sus. • Reconciliation of grade control work with both orebody model and plant figures • Marking out of grade blocks (minimum mining width of 2.5m) • Blast design to separate waste from ore • Selective mining - 2.5m flitches on 10m benches • Blending on ROM pad near crusher to ensure steady feed to plant • High, Medium & Low grade stockpiles and Mineralised waste 19
Exploration - Additional potential below the pit W 2km E Upside from upgrading Inferred resources and underground potential • Potential to add to current reserve, with minimal infill drilling • Hanging wall Inferred resource within pit • Additional Inferred resources just below base of current optimised pit • Ore body is open at depth, with underground potential 20
New Liberty Underground Potential (West – East) 21
Geophysics – New Liberty Exploration Targets Reduced to Pole Aeromagnetics TMI Ground IP 22
New Liberty near mine exploration • Regolith and fact geology mapping to produce near mine map • Re-interpretation of soil geochemistry and geophysics anomalies • Prospect scale mapping and data integration • West Mafa target mapping and pitting BEA Mountain ML W Mafa ¹ Diversion (B) Western Extension Jawaje (C) Jikando (A) 5 km New Liberty 23
New Liberty near mine exploration Regolith understanding key for geochem interpretation • Concealed orebodies • Upper saprolite leaching Regime change W of Mafa River Mapping currently ongoing Relict regime with New Liberty extensive depositional material
West Mafa gold anomaly New Liberty 6km 450m Artisanal workings 1.3 km 25
Near Mine exploration West Mafa • New find, 6km west of New Liberty • 1.3km long, 450m wide gold in soil anomaly • Mineralisation associated with veins and shearing in gneisses and amphibolites • Minor artisanal workings • Bulk of area is soil covered – outcrop is poor. Geological mapping is in progress 26
Summary • Clearly defined orebody with >2km continuous Panned gold from weathered Fe rich soils at New Liberty mineralisation • High grade deposit with both coarse and fine free gold • Strong association of gold mineralisation with geological alteration features and clear geophysical and geochemical signatures Close up of gold nugget from New Liberty • Robust mineralisation model consistent with geology • Grade improves with depth - good underground potential • Considerable potential for additional resources below and around the pit as well as in nearby prospects. 27
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