euromine expo bjorkdal processing june 2016 · suggested flotation capacity expansion 21 ... in...

Bertil NorénProcessing Manager, Björkdalsgruvan

Euromine Expo, Skellefteå – June 15, 2016

A Values-Based and Value-Focused Company

We create exceptional shareholder value through the acquisition of undervalued assets that can rapidly become cash generative, self-fund exploration, establish and maintain high operating margins and return cash to shareholders within a planned period of time. Mandalay is committed to operating safely and in an environmentally responsible manner, while developing a high level of community and employee engagement

WE ARE SUCCESSFUL WHEN:

Our employees live and work safely and experience the personal satisfaction that comes with high performance and recognition

The communities in which we operate value our presence

Our environmental impact is minimized and causes no permanent harm

We have a large, diversified set of customers who are delighted with and compete for our products

Our shareholders realize a superior total return on their investment and support our corporate values.

Our values are visibly demonstrated by strong local management, at the point of impact with or stakeholders, and co-ordinated across the Company for maximum effect

Profitable and Dividend‐Paying: (3.3% yield)*

*Trailing 12 months dividends divided by current market capitalization (June 8, 2016) 2

Mandalay Resources - Björkdalsgruvan

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Björkdal Overview


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Short History: The deposit was discovered in 1983. Terra Mining opened the mine in July 1988 and ran it until it was bought out by William

Resources in 1996 (legal entity: “Terra Mining AB” 1988-1999). William continued to run the mine until June 1999, when the gold price fell sharply and it

was forced to shut down. Production resumed in 2001. From the restart the owners have been “International Gold Exploration”, 2001 to 2003,

“Minmet”, 2003 to 2007, “Gold Ore Resources”, 2007 to 2012. “Elgin Mining Inc”, 2012-2014. Currently: “Mandalay Resources”.

To date, the mine produced about 38,119 kg of gold or 1.23 million ounces (until 2015).


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Quick Plant Facts:37 employees

2015 figures:Throughput ~ 1.3 Mton/yearUtilization ~ 98.18 %

Recovery ~ 88.1%Average head grade ~ 1.22 g/t AuAverage Tail ~ 0.14 g/t Au

Installed nominal grinding power: 315 + 775 + 500 = 1590 kW


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0

10

20

30

40

50

60

70

80

90

100

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200,000

400,000

600,000

800,000

1,000,000

1,200,000

1,400,000

1987 1992 1997 2002 2007 2012

Yearly; Production, Grade, Recovery

Mill feed (ton) Mill feed g/ton Tot.rec. (%)


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0.5

1

1.5

2

2.5

3

3.5

83

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93

1987 1992 1997 2002 2007 2012

Recovery and Feed Grade

Tot.rec. (%) Mill feed g/ton

Simplified Process Flow Sheet

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Björkdalsgruvan Products

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Björkdal Products - Main Components- Sample[%]

Gravity Gravity Flotation KnelsonConc Middling Conc

Fe 6.4 47.3 41.1 16.5S 3.82 31.55 25.4 8.55Si - 5.965 13.4 53.3Ca - 1.95 6.43 7.43Cu 0.07 0.0735 5.78 0.053Mg - 0.4 2.33 1.83Al - 1.45 2.9 9.97

P - 0.062 0.241 0.272Zn Trace 0.013 0.69 0.019As - 0.053 0.017 0.001Zr <0.005 0.304 0.034 0.221Ag 4.2 0.03 0.016 0.004Sb 0.03 0.013 0.022 0.031Te 7.11 1.1 0.055 0.058La - 0.007 0.025 0.022Ce - 0.011 0.044 0.039W 1.1 5.71 0.159 0.496

(Au) % 55.43 0.113 0,000 0.029Pb 5.2 0.85 0.51 0.185Bi 12.19 2.17 0.112 0.175

Au [g/ton] 1500 100 150

Mandalay Resources – Björkdalsgruvan

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Occurrence of Gold In the Björkdal Process Products Neea Heino, M. Sc

Flotation Concentrate

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Foto/SEM study: Neea Heino, GeologicalSurvey of Finland

Flotation Concentrate

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MLA/SEM study: Neea Heino, Geological Survey of Finland

Gravity Middlings

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Foto/SEM study: Neea Heino, Geological Survey of Finland

Gravity Middlings

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Conclusions SEM/MLA Study:

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There is a high degree of liberation in all concentrate products (90-95%)• There is a size effect; liberation drops ~10% from P80 to P95• Electrum is less liberated than gold (Knelson concentrate)

Non liberated Au is associated with silicates, sulphides and tellurides. (Chemical correlations in concentrates are not explained by association)

No significant correlation to any other elements/minerals. • A longer XRF vs Au study is recommended

Projects 2016

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Ongoing projects:• Ore‐sorting with laser scattering (By Tomra sorting solutions)

Upcoming Projects:• Flotation expansion • Extended Tailing Storage Facility

Ore Sorting Layout

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Ore Sorting Layout

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Ore Sorting Layout

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Ore sorting at Björkdal Stockpiled Mixed Low-Grade Material

Sorted Waste – no veins Sorted Ore – with veins

Bulk Test Start Grade End Grade Times Upgraded Waste Rejection Gold Retained g/t Au g/t Au (%) (%)

Underground Ore 1.93 2.97 1.54 43.0 87.0Stockpile Ore 0.81 1.11 1.37 30.0 96.0

Pilot studies confirm that: • Au is contained in fragments of

white quartz vein material, not in black wallrock material

• Can optically sort out 40+% of black rock and only lose a few % of gold recovery

Potential to upgrade low-grade material or even high-grade material to increase mill head grade, producing more gold from existing mill capacity

Onsite pilot plant in operation as of May 20 on 60,000 – 80,000 t test; good visual results after first days

Expect test results in July-August

Suggested Flotation Capacity Expansion

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Objective:• Increase flotation volume with 60 m3

• Implement two stage cleaning• Decrease Au in tail by 0.03 – 0.06 g/t

Estimated project time: 9-12 Months

In co-operation with Outotec (Sweden) ABProject Manager: Anders Rutdal, Outotec


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R² = 0.8479

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0.5

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2.5

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3.5

0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40

Flot

Fee

d; A

u [g

/ton]

Tail; Au [g/ton]

Flot Feed vs Tail3 (g/ton) (No outliers removed) (24th Feb - 15th April)


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R² = 0.536

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0.2

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1.2

1.4

0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50

Flot Fee

d; Au [g/ton

]

Tail; Au [g/ton]

Flot Feed vs Tail3 (g/ton)

Suggested Flotation Capacity Expansion – Layout

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Extended Tailing Storage Facility


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euromine expo bjorkdal processing june 2016 · suggested flotation capacity expansion 21 ... in...

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