ROCK FORAGE CONSULTING SERVICES SITE VISIT REPORT - London … · Report No. RFM_2016_083 16 January 2017 GSR Site Visit Report 3 ROCK FORAGE CONSULTING SERVICES SITE VISIT REPORT

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Report No. RFM_2016_083 16 January 2017 GSR Site Visit Report 3

ROCK FORAGE CONSULTING SERVICES

SITE VISIT REPORT

SUMMARY REPORT OF SITE VISIT TO GOLDEN SAINT FIELD OPERATIONS

IN SIERRA LEONE, 30 NOVEMEBR – 11 DECEMBER 2016

Report No. RFM_2016_083

16 January 2017

AUTHORS: Pierre Fourie, Dr. John D. Ward, Pierre de Jager

PO Box 11719 Zwartkops, Centurion, 0051, South Africa

11 Aster Street, Somerset West, 7130, South Africa

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TABLE OF CONTENTS

1 INTRODUCTION .......................................................................................................... 1 2 EXPLORATION TARGET PROVISIONAL ALLUVIAL INVENTORIES .................................... 1 3 BAJA PROJECT: OBSERVATIONS & RECOMMENDATIONS............................................... 6

3.1 Bulk Sampling .......................................................................................... 6 3.2 Sample Treatment Plant ........................................................................... 6 3.3 Proposed exploration program for Baja project ........................................... 6

4 TONGO ...................................................................................................................... 11 5 MOA PROJECT ............................................................................................................ 11 6 PROJECT CONSTRAINTS ............................................................................................. 11 7 GENERAL ................................................................................................................... 11 8 COMPETENT PERSON STATEMENT .............................................................................. 11 9 GLOSSARY OF TECHNICAL TERMS .............................................................................. 12

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1 INTRODUCTION

Pierre de Jager, consulting geologist, visited the GSR projects in Sierra Leone from 30 November 2016 to 11 December 2016. Baja and Tongo licences are the only sites where active exploration is currently in progress. No exploration currently being undertaken on the Moa licence due to logistical constraints. Thus for the purpose of this report the author will concentrate on the requirements needed by the GSR Sierra Leone team to lift the current exploration targets to an inferred resource level of confidence in the Baja and Tongo licences, respectively.

This site visit focussed on the Sewa River alluvial deposits within the Baja licence and the Woa River alluvial deposits within the Tongo licence. From the field observations on terrace and floodplain (flats) distributions, historical workings and GSR exploration to date, provisional estimates of the extent of, and possible diamond mineralisation within, the Baja and Tongo alluvial exploration targets are given as baselines from which to work towards the inferred resource level of confidence required for these respective licences. Each exploration target in their respective licence is critically analysed with proposed solutions to lift these targets to the required inferred resource level of confidence.

2 EXPLORATION TARGET PROVISIONAL ALLUVIAL INVENTORIES

From the field investigations and preliminary mapping undertaken to date, the principal accessible diamond and gold bearing alluvial deposits are found in the flats (floodplains) and lower terraces adjacent to the Sewa River (Baja Licence) and the Woa River (Tongo licence), respectively. In order to build up preliminary inventories of these respective exploration targets, the following assumptions have been used:

• Width of the flats (floodplains) and lower terraces: 200 m;

• Gravel density: 2

• Gravel thickness: 0.5 m

• Overburden thickness: variable, 4 – 6 m;

• Extent of historical mining: 50% of original area assumed to have been

mined;

• Historical grades from Hall (1965) range from 29 carats per hundred tonnes

(cpht) to 109 cpht (average = 47 cpht);

• For the purpose of the initial inventory estimations of diamond

mineralisation, grades of 10 cpht and 25 cpht have been applied to estimate

the remaining potential within the Baja and Tongo licences, respectively. For

the alluvial gold, grades of 0.03 grams/tonne (g/t) and 0.05 g/t have been

used for those initial estimates.

Note that the alluvial inventory estimates presented below are merely guidelines for the potential mineralisation in the Baja licence and Tongo licence exploration targets, although historical results have been well summarised by Hall (1965).

GSR will explore these Baja and Tongo exploration targets further by GSR in order to move an Inferred Resource level of confidence, focussing on:-

• Mapping to delineate more accurately the alluvial deposits;

• Augering and/or pitting to determine basal gravel thickness and distribution,

as well as overburden thickness;

• Excavate bulk sample trenches at regular intervals (approx.. 500 m spacing)

across the palaeo-flow direction of the alluvial deposits and treat basal

gravels for diamond and gold content to determine range of grades;

• Build up size frequency distribution records of the alluvial diamond

populations per target and estimates of their potential revenues.

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• Synthesis of these exploration data to delineate inferred resources in the

Baja and Tongo licences.

From the initial inventories (Tables 1-4 below), it is anticipated that there is between 2,700,000 and 3,900,000 tonnes of mineralised basal gravels remaining in the Baja (Tables 1 & 2) and Tongo (Tables 3 & 4) licences, respectively. From the site visit, these estimates are considered conservative and further exploration will define the alluvial targets more accurately and to a higher level of confidence, initially as an inferred resource.

Baja project:

The Baja project has been divided into 2 areas, Sewa North and Sewa South (see Map 1). Provisional inventories are summarised in the Tables 1 and 2 below. The anticipated total tonnes of basal mineralised gravel is approximately 1,800,000 to 2,400,000 tonnes that could host between 210,000 – 525,000 carats of diamonds and some 63 – 105 kgs of alluvial gold.

TABLE 1: Sewa North Provisional Inventory

Length (m)

Width (m)

Gravel thickness

(m)

50% Remaining

Target (tonnes)

Possible Carat

Inventory at 10 cpht

Possible Carat


Possible Gold

Inventory (kg) at 0.03 g/t

Possible Gold

Inventory at 0.05 g/t

4,000 200 0.5 400,000 40,000 100,000 12 20

NOTE: Strip ratio expected to be in the range of 8:1 to 12:1.

TABLE 2: Sewa South Provisional Inventory

Length

(m)

Width (m)

Gravel Thickness

(m)

50% Remaining

Target (tonnes)

Possible Carat


Possible Carat


Possible Gold

Inventory (kg) at 0.03

g/t

Possible Gold


g/t

8,500

200 X2 (east & west

banks)

0.5 1,700,000 170,000 425,000 51 85


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MAP 1. BAJA LICENCE, showing Sewa North and Sewa South exploration targets along the Sewa River

Sewa

North

Sewa

South

Site 4

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Tongo Project

The Tongo project has also been divided into 2 targets, a Tongo North exploration target and a Tongo South exploration target (see Map 2). Provisional inventories are summarised in the Tables 3 and 4 below. The anticipated total tonnes of basal mineralised gravel is approximately 900,000 to 1,500,000 tonnes that could host between 120,000 – 300,000 carats of diamonds and some 36 – 60 kgs of alluvial gold.

TABLE 3: Tongo North Provisional Inventory

Length (m)

Width (m)

Gravel thickness

(m)

50% Remaining

Target (tonnes)

Possible Carat


Possible Carat


Possible Gold


g/t

Possible Gold


g/t

4,000 200 0.5 400,000 40,000 100,000 12 20


TABLE 4: Tongo South Provisional Inventory

Length (m)

Width (m)

Gravel thickness

(m)

50% Remaining

Target (tonnes)

Possible Carat


Possible Carat


Possible Gold


g/t

Possible Gold


g/t

4,000

200 X2

(east & west banks)

0.5 800,000 80,000 200,000 24 40


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MAP 2: TONGO LICENCE, showing Tongo North and Tongo South exploration targets

along the Woa River.

Tongo

North

Tongo

South

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3 BAJA PROJECT: OBSERVATIONS & RECOMMENDATIONS

3.1 Bulk Sampling

No open holes to see in situ gravel. The measurements of the bulk sample trench and pit dimensions, including overburden thickness, basal gravel thickness and bedrock lithology, to be standardised and followed more rigorously.

3.2 Sample Treatment Plant

At the sample site, the oversize gravel is removed by hand (Fig. 1). The plant feed is also highly manual (Fig. 2) which leads to erratic feed rate into the plant and a security risk for the larger diamonds. The sample plant produces a screened product, rather than a concentrate, which has a large range in grit and gravel size from 3 mm to 80 mm (Fig. 3). This range in grit and gravel sizes is too large for effective jigging which is done manually in the river (Fig. 4). Therefore wash plant screened product needs to be further classified into size ranges where jigging is effective (2:1 and 3:1 ratio rules need to be applied). Simple mechanical jigs (Plietz, Bushman, Panama type alternative to manual jigging need to be investigated).

The current tracer tests using metal tracers should be replaced with more conventional jig tracers.

3.3 Proposed exploration program for Baja project

Proper mapping of area, recording past workings (Fig. 5) and whatever other exposures that may be available. Shuttle radar imagery that is readily available should supplement whatever other remote sensing imagery is available. Locating dykes and amphibolite zones are very important for identifying alluvial trapsites.

Gravel Distribution from Augering: Auger drill samples to be drilled very 50m along drill lines spaced very 250m in between trenches. This will mean 8 lines with 5 holes per line. Hand-held augers are available for rent in Sierra Leone and this technique and availability of units should be investigated as a matter of urgency. This technique will allow estimates of overburden and gravel thicknesses to be determined relatively easily.

Bulk Sampling: In order to lift the exploration targets to inferred resource levels, bulk sample trenches need to be cut with an excavator across the strike of the alluvial deposits. Thus the bulk sample trenches will be some 100-200 m long, depending on flats and lower terrace widths, and spaced at about 500 m intervals. These trenches should as wide as the excavator bucket until basal gravels are intersected, after which the trench needs to be opened laterally to 10m wide to generate gravel for the bulk sample. If the gravel horizon is longer than 25m, then bulk samples are removed in 25 m paddocks to give some 250 tonnes per sub-sample.

From the initial mapping of the flats and lower terraces, Sewa North will require 9 bulk sample trenches and Sewa South some 17 in order to cover the exploration targets adequately.

Proper measurements must be taken at least every 10m along a longwall, including overburden thickness, gravel thickness as well as a bedrock (footwall) description (e.g. granite, amphibolite or dolerite dyke). Photographs must also be taken at these 10m longwall intervals and a proper scale (long stick spray-painted every 0.5m) must be used. Close up photographs of the basal gravels (with scale) should also be taken where possible, bearing the wet underfoot conditions in mind.

The floor of the bulk sample onto bedrock must be cleaned properly and the water pumped out whilst the excavation and logging is in progress. A sump should be excavated closest to river to facilitate draining and pumping. This procedure very necessary for alluvial gold recovery as most of this heavy precious metal occurs within 5 cm (0.05 m) of the basal contact.

Bulk Sample Treatment Plant: Reduce oversize screen size from 80mm to 16mm for the sampling exercise. The product will thus be +3mm-16mm, which will allow for the recovery of diamonds in the 0.23 cts/stn to about 35 cts/stn size range. However, this size range will need to be screened into smaller size fractions of 3-6mm, 6-12mm, +12mm for

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effective jigging. The acquisition of jigs should be considered to replace the manual methods currently being used. The small barrel screen (at Bo office) to be modified to feed into jig to reduce access to the gravel.

The bulk sample plant to be tested at least 3 times a week with conventional diamond tracers.

Improve the jigging technique with dedicated jigs away from the river and then sort directly from the jigs on a sorting table. This will eliminate the manual jigging and sorting currently undertaken in the river.

Final sorting is to be done in a proper enclosed area on a sorting table with minimal people present (2 to 3 people present and depending on statutory requirements). All to sign off on recoveries after weighing singletons and the daily production, then photographed and properly sealed before put into proper safe. A proper procedure for the transport and intake of parcels to Freetown to be drawn up.

General: More security needed at plant site. Access to the bulk sample plant and final sorting area to be restricted. Currently, too many people moving in, out and through these sensitive areas. Areas should be enclosed and security present, including consideration for additional canine security.

Logistics: Ideally, communication on each site should facilitated such that contact can be made with the other operational centres such as the Bo office and Freetown office.

Due to harsh road conditions, each site should have its own vehicle. Very difficult to move from one site to another in a respectable time frame.

Each site should have its own manager. Professional staff is needed.

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FIGURE 1 - Baja site 2: Handsorting of oversize

FIGURE 2 - Baja site 2: Handsorting and feeding of gravel by several human operators

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FIGURE 3 - Baja site 2: Screened product rather than concentrate from washplant to be jigged in river

FIGURE 4 - Baja site 2: Large size range screened product rather than a concentrate then jigged and sorted manually in river

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FIGURE 5 - Baja site 2: Old mining pit where gravel has been extracted

FIGURE 6- Tongo mining site 2: Stripping overburden while pumping water out

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4 TONGO

No washing activities at present on site. Previous bulk sampling pit is being extended towards river (Fig. 6). Unfortunately, no proper measurements or photographs available to determine stripping, gravel thickness or bedrock lithology.

The present bulk sampling pit (Fig. 6) will only access limited amount of gravel and will do little to improve the present exploration target level of confidence towards the inferred resource level. A similar exploration programme as outlined for the Sewa North and Sewa South targets in the Baja licence (Section 3) should be implemented for the Tongo North and Tongo South targets.

The Tongo kimberlite exploration project is of great importance and should be started as soon as possible to take advantage of the current dry season. It is recommended that focused soil sampling to search for kimberlite indicator minerals (KIMs) is undertaken over the highest priority aeromagnetic anomalies already identified from that geophysical campaign. In addition, ground magnetic surveys should be planned for those targets that return positive kimberlite indicator minerals.

5 MOA PROJECT

No exploration activities at present on Moa project. Vehicle and personnel constraints.

A proper soil sampling program for gold needs to be executed urgently if the current dry season is to be maximised. Geochemical sampling for chrome should also be considered as this particular greenstone belt has a history of chrome mining and the current chrome prices warrant the following up om any such opportunities.

6 PROJECT CONSTRAINTS

Most of the project constraints have already been covered in the Baja and Tongo sections. The author feels strongly that more professional management is needed on the ground to ensure that the bulk sampling methods and bulk sample plant problems are solved correctly. Logistically, more vehicles are needed, as are 3 Garmin hand-held GPS units for exploration locality recordings.

In order to have a good control on the bulk sample results, there must be a daily report covering all the activities per exploration target site. This report must include, inter alia, tonnes washed, stones recovered and their respective carat weights (preferably with photographs), gold recovered and weight in grams (photographs as well), treated gravel description with photographs and then also photographs of the bulk sample trench from where the gravel has been excavated.

7 GENERAL

The GSR Sierra Leone project, with exploration targets already identified and partly sampled in the Baja and Tongo licences, is an excellent alluvial diamond and gold opportunity with primary kimberlite potential. However, a more professional approach is needed to move these exploration targets to the higher confidence, inferred resource levels.

8 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

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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.

9 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 target An Exploration Target is a statement or an estimate of the exploration potential of a (diamond) deposit in a defined geological setting where the statement or estimate, quoted as a range of tonnes and a range of grade, relates to the mineralisation for which there has been insufficient exploration to estimate a Mineral Resource.

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 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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ROCK FORAGE CONSULTING SERVICES SITE VISIT REPORT - London … · Report No. RFM_2016_083 16 January 2017 GSR Site Visit Report 3 ROCK FORAGE CONSULTING SERVICES SITE VISIT REPORT