ROCK FORAGE CONSULTING SERVICES SITE VISIT REPORT · ROCK FORAGE CONSULTING SERVICES SITE VISIT...

ROCK FORAGE CONSULTING SERVICES

SITE VISIT REPORT

SUMMARY REPORT OF SITE VISIT TO GOLDEN SAINT FIELD OPERATIONS

IN SIERRA LEONE, 27-30 JUNE 2016

Report No. RFM_2016_080

17 August 2016

AUTHORS: Pierre Fourie, Dr. John D. Ward

PO Box 11719 Zwartkops, Centurion, 0051, South Africa

112 Anton Street, Pretoria, 0081, South Africa

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Report No. RFM_2016_080 17 August 2016 GSR Site Visit Report 2

EXECUTIVE SUMMARY

Rock Forage conducted a site visit to the Golden Saint Resources Ltd (Sierra Leone) field operations at the end of June 2016, the principal objectives being to inspect the upgraded Dove Jig Treatment Plant ahead of re-commencing the treatment of the Stockpile 1 alluvial bulk sample from the Woa River low

terrace gravels in the Tongo Licence, evaluate the sample setting and excavated gravels from the low

terrace of the Sewa River at Site 2 in the Baja Licence and to inspect several second-hand excavators available in Sierra Leone for use in the mini-bulk sampling campaigns planned initially for the Tongo

and Baja Licences. The site visit was conducted by Mr Pierre Fourie, Mining Engineer, with resource aspects of this trip followed up with Dr John Ward in South Africa. Due to the onset of the Wet Season

at the time of the visit, only the Tongo and Baja Licences were visited.

The Dove Jig Treatment Plant, currently located in the Tongo Licence, had been upgraded to improve

the screening and the gold recovery efficiencies. Treatment of the Stockpile 1 alluvial mini-bulk sample

from the Woa River low terrace gravels, which commenced on 27 June 2016, was subsequently completed on 10 August 2016 with alluvial diamonds and fine gold recovered from 140 tonnes under

well-controlled conditions. A recovered diamond grade of 9.1cpht (0.47 cts/stn) was realised with a gold grade of 0.04g/t.

The Site 2 alluvial bulk sampling locality on the low terrace of the Sewa River in the Baja Licence was visited on foot. Access to this site will not be possible until the onset of the Dry Season, but all plant

equipment destined for this campaign was recovered successfully from the Zimmi project in spite of

the Wet Season rains in early August 2016.

None of the second-hand excavators screened in Sierra Leone were suitable for the exploration

programme and thus alternative sources in the Far East and South Africa are being investigated.

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TABLE OF CONTENTS

EXECUTIVE SUMMARY .................................................................................................................. ii 1 INTRODUCTION ...........................................................................................................1 2 DOVE JIG TREATMENT PLANT IN TONGO LICENCE ........................................................1 3 TONGO ALLUVIAL MINI-BULK SAMPLE (STOCKPILE 1) ...................................................7

3.1 Treatment Process .....................................................................................7 3.2 Sample Results ........................................................................................ 13

4 SEWA RIVER, BAJA LICENCE ....................................................................................... 14 5 SECOND-HAND EXCAVATORS IN SIERRA LEONE .......................................................... 15 6 CONCLUSIONS & RECOMMENDATIONS ....................................................................... 15 7 COMPETENT PERSON STATEMENT .............................................................................. 16 8 GLOSSARY OF TECHNICAL TERMS .............................................................................. 16

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LIST OF FIGURES

Figure 1: Tongo Dove Jig Plant ......................................................................................................2 Figure 2: Dove 200 treating smaller fraction (+3-5mm) ...................................................................2 Figure 3: Dove 100 treating larger fraction (+5-20mm) ...................................................................3 Figure 4: Diesel water pump ..........................................................................................................3 Figure 5: Feed bin to trommel screen .............................................................................................4 Figure 6: Feed bin 30mm grid ........................................................................................................4 Figure 7: Scrubber/Trommel Screen with 3mm and 5mm screening sections ....................................4 Figure 8: Dove 100 trommel screen oversize showing almost no clay balls (effective scrubbing) ........5 Figure 9: Dove 100 trommel screen oversize (high % +5-20mm) ....................................................5 Figure 10: Dove 100 trommel screen ..............................................................................................6 Figure 11: Dove 100 trommel screen oversize (almost no +5-20mm) ...............................................6 Figure 12: Clean jig tails ................................................................................................................7 Figure 13: Stockpile 1....................................................................................................................8 Figure 14: Stockpile 1 transported to plant location by wheelbarrow ................................................8 Figure 15: Interim stockpile at plant ...............................................................................................9 Figure 16: Standard bucket for measuring plant feed ......................................................................9 Figure 17: Head-buckets for transporting gravel to the scrubber feed bin ....................................... 10 Figure 18: Scrubber feed bin ....................................................................................................... 10 Figure 19: Water washing of gravel into scrubber feed bin ............................................................ 11 Figure 20: Sierra Leone hand sieve .............................................................................................. 11 Figure 21: Hand sieve concentrate ............................................................................................... 12 Figure 22: Recovered gold ........................................................................................................... 12 Figure 23: Sewa River, Baja license, Site 2, Stockpile 1 ................................................................. 14 Figure 24: Baja Site 2 Stockpile 1 gravel ....................................................................................... 15

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1 INTRODUCTION

Rock Forage conducted a site visit to the Golden Saint Resources Ltd (Sierra Leone) field operations on 27 to 30 June 2016, the principal objectives being:-

Inspect the upgraded Dove Jig Treatment Plant ahead of re-commencing the treatment of the Stockpile 1 alluvial bulk sample from the Woa River low terrace gravels in the Tongo Licence;

Ensure that the recommended additional sample data collection parameters, which would provide further resource and plant operational information, were in place prior to the re-commencement of the Stockpile 1 alluvial bulk sample in the Tongo Licence;

Evaluate the sample setting and excavated gravels from the low terrace of the Sewa River at Site 2 in the Baja Licence; and

Evaluate several second-hand excavators available in Sierra Leone for use in the mini-bulk sampling campaigns planned initially for the Tongo and Baja Licences.

The site visit was conducted by Mr Pierre Fourie, Mining Engineer, with resource aspects of this trip followed up with Dr John Ward in South Africa. Due to the onset of the Wet Season at the time of the visit, only the Tongo and Baja Licences were visited.

2 DOVE JIG TREATMENT PLANT IN TONGO LICENCE

The Dove Jig Treatment Plant on the eastern side of the Woa River in the Tongo Licence was further upgraded, focussing mainly on improving the screening capability in the Dove 200 and Dove 100 units and the recovery of fine (<3 mm) alluvial gold (Figures 1, 2 & 3). This combination allows for two sized jig concentrates +3-5mm and +5-20mm (screen sizes). A gold plant was adapted to serve as a scrubber to break up and remove clay minerals in the plant feed and to separate the plant feed into: <3mm that is washed over a gold mat to recover the contained gold; +3-5mm that is jigged in the Dove 200; and +5mm that is further screened in the Dove 100 trommel screen resulting in a +5-20mm undersize that is then jigged in the Dove 100.

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Figure 1: Tongo Dove Jig Plant

Figure 2: Dove 200 treating smaller fraction (+3-5mm)

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Figure 3: Dove 100 treating larger fraction (+5-20mm)

A diesel water pump supplies ample water to the plant from the bulk sampling cut. When gravel extraction from the cut recommences water can be pumped directly from the Woa River.

Figure 4: Diesel water pump

Feed to the scrubber/trommel screen is via a feed box with a 30mm grid that removes oversize material. Water is added to the process in the feed box washing the gravel into to plant. This allows for a hands-off feed to the plant.

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Figure 5: Feed bin to trommel screen

Figure 6: Feed bin 30mm grid

Figure 7: Scrubber/Trommel Screen with 3mm and 5mm screening sections

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The Dove 100 trommel screen oversize was inspected for the presence of clay balls. Clay balls could hold diamonds and prevent them from reaching the jig section of the plant leading to diamond losses. No significant amount of clay balls were observed suggesting that the scrubbing process in the gold scrubber/trommel screen is effective.

Figure 8: Dove 100 trommel screen oversize showing almost no clay balls (effective scrubbing)

A high percentage of +5-20mm gravel was observed in the Dove 100 trommel screen oversize pile. This indicated screen overrun and could lead to diamond losses. The angle on the trommel screen was reduced and this fixed the overrun problem. The oversize pile was picked up and re-treated.

Figure 9: Dove 100 trommel screen oversize (high % +5-20mm)

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Figure 10: Dove 100 trommel screen

Figure 11: Dove 100 trommel screen oversize (almost no +5-20mm)

The Dove 100 Jig tails were inspected and showed a light concentrate suggesting that the jigging process was efficient.

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Figure 12: Clean jig tails

3 TONGO ALLUVIAL MINI-BULK SAMPLE (STOCKPILE 1)

3.1 Treatment Process

Treatment of the Stockpile 1 alluvial mini-bulk sample from the Woa River low terrace gravels, which commenced on 27 June 2016, was subsequently completed on 10 August 2016 with alluvial diamonds and fine gold recovered from 140 tonnes under well-controlled conditions.

The processing of the mini-bulk samples (<500 tonnes) is done under the supervision of the Senior Geologist, assisted by the Jig Plant Supervisor. Breakdowns were repaired reasonably quickly notwithstanding the wet underfoot conditions.

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Figure 13: Stockpile 1

Figure 14: Stockpile 1 transported to plant location by wheelbarrow

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Figure 15: Interim stockpile at plant

Plant feed tonnes is measured by weighing a standard size bucket and counting the amount of buckets fed to the plant. The bucket takes 11.2kg of material (wet weight).

Figure 16: Standard bucket for measuring plant feed

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Figure 17: Head-buckets for transporting gravel to the scrubber feed bin

Figure 18: Scrubber feed bin

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Figure 19: Water washing of gravel into scrubber feed bin

Concentrate from the Dove 100 and Dove 200 is treated by hand using a Sierra Leone hand sieve and diamonds removed by hand sorting on the sieve under senior supervision only. This methodology was observed and found to be efficient.

Figure 20: Sierra Leone hand sieve

The concentrate forming in the centre of the sieve showed a majority of heavy minerals with lots of green epidosite present.

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Figure 21: Hand sieve concentrate

A small amount of gold was recovered from the gold mat.

Figure 22: Recovered gold

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3.2 Sample Results

The operational parameters recorded running time, treatment time, breakdown time, fuel consumption of the power pack (generator) driving the Dove Jig Treatment Plant and other lubricants used, all which provide information for later designs of sample treatment plants.

The resource parameters, used to characterise the diamond and gold content of the Woa River alluvial gravels, recorded include:-

Percentage of oversize clasts in alluvial gravels;

Weight of wet gravel loaded manually into the Dove Jig Treatment Plant. A wet weight is easier to record during the Wet Season and is estimated to be in the order of 10-5%. The alluvial gravels are fed into the Dove Jig Treatment plant manually using buckets that are weighed (tonnes);

Number of diamonds recovered, weighed as single stones ( in carats; 1 carat = 0.2 gram) in order to build up a size frequency distribution to characterise the Woa River alluvial diamond population to assist with future developments (Table 1); and

Weight of the alluvial gold (in grams), to date all of which has been recovered from the -3mm fraction (Table 1).

Table 1: Results of the treatment of Stockpile 1 alluvial mini-bulk sample to completion where the oversize component is estimated to be some 8% of the total gravel processed

RESOURCE PARAMETER VALUE

Dates Treated 27 Jun 2016 to 10 Aug 2016

Sample Origin Woa River low terrace (left bank)

Sample Number TS1

Wet Weight (10% moisture) 156 tonnes

Dry Weight (tonnes @ 10% moisture content) 140 tonnes

Number of diamonds (stones = stn) 27 stns

Weight of diamonds (carats; 1 ct = 0.2 grams) 12.79 cts

Diamond content / grade (carats per 100 tonnes) 9.1 cpht

Average diamond size (cts/stn) 0.47 cts/stn

% diamonds 1-2 cts weight 15%

% diamonds 0.5 – 0.99 cts weight 15%

% diamonds 0.01 – 0.49 cts weight 70%

Weight of gold (grams; gm) 5.37 grams

Gold content/grade (grams per tonne, g/t) 0.04 g/t

With the first 140 tonnes treated from Stockpile 1 (sample number TS1) under well controlled conditions, the average grade for the dry gravels (moisture content estimated

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to be 10%) is approximately 9.1 carats per hundred tonnes (cpht) with an average stone size of 0.47 cts/stn. The alluvial free gold content averages 0.04 g/t.

Note that SP1 gravels were not fully basal gravels, which is where the best placer (heavy mineral) concentrations tend to occur in alluvial / fluvial and marine systems. Moreover, these results are the start of building up grade and diamond size (and thus population) statistics to determine more accurately the estimated resource potential of the Woa River low terraces in the Tongo Licence.

4 SEWA RIVER, BAJA LICENCE

In parallel with the exploration currently underway in the Tongo licence, a second site, Site 2, was selected for alluvial mini-bulk sampling on the low terrace of the Sewa River using the GSR treatment plant that has been operational in the Zimmi project area.

Access to the Site 2 alluvial bulk sampling locality will not be possible until the onset of the Dry Season, but all plant equipment destined for this campaign was recovered successfully from the Zimmi project in spite of the Wet Season rains in early August 2016.

This sampling has been placed on hold until the start of the upcoming 2016-2017 Dry Season.

Figure 23: Sewa River, Baja license, Site 2, Stockpile 1

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Figure 24: Baja Site 2 Stockpile 1 gravel

5 SECOND-HAND EXCAVATORS IN SIERRA LEONE

In order to speed up the alluvial mini-bulk sampling programme, GSR plans to buy its own 20 tonne excavator to maximise digging to basal gravels in the low terraces – at least, commencing in the Tongo and Baja Licences with later deployment to the Moa Licence. However, initial inspections have proved disappointing as the earthmoving equipment in general, and the excavators specifically, have excessive operating hours during which times the general maintenance levels have been lower than required. Consequently, the inherent value is low and Rock Forage is investigating potential sources in South Africa, whilst GSR office in Perth is looking into Middle to Far East sources.

6 CONCLUSIONS & RECOMMENDATIONS

With the Dove Jig Treatment Plant upgraded and modifications completed under Rock Forage’s guidance, the first well-controlled alluvial mini-bulk sample of 140 tonnes (dry weight) of gravels from the Woa Rover low terrace in the Tongo licence was completed between 27 June 2016 and 10 August 2016. This small sample, fed manually through the Dove Plant, yielded 27 diamonds weighing 12.79 carats, giving an initial grade of 9.1 carats per hundred tonnes at an average stone size of 0.47 carats per stone. Some 5.37 grams of gold were also recovered, giving a grade of 0.04 grams per tonne. Some 15%

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of the stones were between 1 – 2 carats, with a further 15% falling in the 0.5 – 0.99 range. This represents the start of systematic exploration to determine the alluvial diamond and gold resource potential of the Woa River valley deposits on the Tongo Licence.

Cleaning of the bedrock to ensure that the basal gravel is extracted is critical although difficult during the wet season. Proper bedrock cleaning might represent some upside to the diamond and gold grades. Test pits to establish the depth of the basal gravel in the stripped pit should be considered.

Sampling of the Sewa River low terrace alluvial gravels, using a second plant, at Site 2 has been postponed until the onset of the Dry Season as vehicular traffic is currently impassable in the Wet Season. The routing of a suggested vehicular road access to Site 2 should be reconsidered in line with the overall exploration strategy on the license.

A second-hand, 20 tonne (approximately) excavator to speed up the alluvial mini-bulk sampling programme is likely to be acquired from South Africa or Far East, as these earthmoving machines are, to date, not in price-worthy conditions in Sierra Leone.

7 COMPETENT PERSON STATEMENT

The information in this report that relates to the Exploration Targets is based upon information compiled by Dr John D Ward (Pr. Sci. Nat; PhD) who is an Independent Consultant employed by Rock Forage Mining Limited and is a Fellow of The Geological Society of South Africa. Dr Ward has sufficient experience relevant to the style of mineralisation and type of deposit under consideration and the activity in which he is undertaking to qualify as a Competent Person under the 2012 Edition of the Australasian Code for Reporting Exploration Results, Mineral Resources and Ore Reserves (JORC Code). Dr Ward consents to the inclusion in a release of the matters based on his information in the form and context in which it appears.

8 GLOSSARY OF TECHNICAL TERMS

alluvial a mineral deposit made up of mobile sediment and/or soil

bedrock the lithified rock that lies under the loose softer material (regolith) at the surface of the Earth

carat standard measure of diamond weight (0.2grams)

diamondiferous containing diamonds

epidosite highly altered epidote (calcium aluminium iron sorosilicate mineral) and quartz bearing rock

exploration targets the three exploration licenses held by GSR in Sierra Leone viz. Baja (EL87/2011), Tongo (EL86/2011) and Moa (EL07/2012) targeted for diamond and gold exploration

basal gravel composed of unconsolidated rock fragments that have a general particle size range and include size classes from granule- to boulder-sized fragments situated at the bottom of a gravel sequence

heavy minerals a suite of accessory minerals of a sedimentary rock or sediments having specific gravities greater than 2.9

terrace remnant of the former floodplain of a stream or river

trommel screen a trommel screen, also known as a rotary screen, is a mechanical screening machine used to separate materials, mainly in the mineral and solid-waste processing industries. It consists of a perforated cylindrical drum that is normally

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elevated at an angle at the feed end. Physical size separation is achieved as the feed material spirals down the rotating drum, where the undersized material smaller than the screen apertures passes through the screen, while the oversized material exits at the other end of the drum.

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