Aureus Mining New Liberty Project Geology February 2014 Contents - - PowerPoint PPT Presentation

Aureus Mining New Liberty Project Geology February 2014

Contents

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• Location and Regional context
• Deposit geology
• Resources and Reserves
• Grade Control
• Underground potential
• Near-mine exploration potential

New Liberty: Established Infrastructure

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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

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Location Map and License Areas

New Liberty

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Exploration Opportunities: 1,470km2 Licence Portfolio

New Liberty

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New Liberty: Project History

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New Liberty: Infrastructure Layout

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New Liberty Exploration Camp and Pit Outline

Simplified Geology Showing Mineralisation

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Section 17 Section 25

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New Liberty: Sections Showing Mineralisation Zones and Grades

16m @ 4.43g/t

K342 K343 K347 K433 K492

9m @ 7.29g/t 28m @ 3.32g/t 21m @ 3.86g/t 4m @ 1.28g/t

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New Liberty: Relationship Between Alteration & Gold Mineralisation

Mineralised zone (red) Magnetic depletion (grey) Pit outline

Host rock and Alteration Margin Signatures

Gold associated with low:

• Magnetic

susceptibility

• Sodium
• Potassium
• Rubidium

and high:

• silicification
• Sulphur
• Arsenic
• Tungsten

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Margins of Phlogopite mica, Magnesium, Potassium, Sodium, Rubidium

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

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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

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New Liberty: Oblique View Showing Mineralisation and Pit Outline

Exploration camp West East

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East West

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New Liberty: Sections Showing Mineralisation Zones and Grades

Section 17 Section 25

0 – 0.8 0.8 – 2.0 2.0 – 4.0 > 4.0 Au g/t

Underground Potential

• 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 – Inferred: 5,730,000t at 3.2 g/t (for 593,000 ounces)1 – Total M & I: 1,143koz at 3.63g/t;

New Liberty: Resource and Reserves

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1 Cut off grade = 1.0 g/t 2 Cut off grade = 0.8 g/t

Footwall Zone

2km 500m

Larjor Latiff Kinjor Marvoe

Reserve Classification Tonnes Gold (g/t) Gold (koz) Proven 700,000 4.4 99 Probable 7,800,000 3.3 825 Total Reserve2 8,500,000 3.4 924

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

West East

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

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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

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Grade Control

Exploration - Additional potential below the pit

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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
• ptimised pit
• Ore body is open at depth, with underground potential

2km E W

New Liberty Underground Potential (West – East)

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Geophysics – New Liberty Exploration Targets

Reduced to Pole Aeromagnetics

Ground IP TMI

New Liberty near mine exploration

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¹

• 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

5 km New Liberty W Mafa Jikando (A) Jawaje (C) Diversion (B)

BEA Mountain ML

Western Extension

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 New Liberty

Relict regime with extensive depositional material

West Mafa gold anomaly

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1.3 km 450m New Liberty 6km

Artisanal workings

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

Near Mine exploration

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Summary

• Clearly defined orebody with >2km continuous

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

• 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.

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Panned gold from weathered Fe rich soils at New Liberty Close up of gold nugget from New Liberty

Thank you

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