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PERSEUS MINING LIMITED — Capital/Financing Update 2015
Apr 19, 2015
46513_rns_2015-04-19_efc3276a-9bcf-45eb-bba1-f8103d02327c.pdf
Capital/Financing Update
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NEWS RELEASE
20 April 2015
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UPDATED LIFE OF MINE PLAN FOR PERSEUS MINING’S EDIKAN GOLD MINE
Perseus Mining Limited (“Perseus”) (ASX/TSX: PRU) is pleased to announce details of its updated Life of Mine Plan (“LOMP”) for the Edikan Gold Mine (“EGM”) in Ghana, West Africa.
HIGHLIGHTS
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Independently estimated Proved and Probable Ore Reserves for the EGM total 61.6 Mt of ore grading 1.2 g/t of gold and containing approximately 2.35 Mozs of gold as at 1 February 2015.
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The revised LOMP involves mining and processing of ore from seven optimised open pits designed using US$1,200/oz pit shells and input costs based on actual operating experience and recently contracted supply agreements.
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For the period from FY2016 to FY2023 inclusive, average gold production of 240,000 ounces/year at an average all-in site cash[1] cost of US$937/ounce.
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Current FY2015 production and cost guidance of 200-210kozs of gold at an all-in site cash cost of US$1,075-1,125/ounce remains unchanged by the updated LOMP.
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Value of future cash flows contribute materially to the underlying value of Perseus as follows:
| NET PRESENT VALUE (US$M) OF EDIKAN”S FORECAST CASHFLOWS | NET PRESENT VALUE (US$M) OF EDIKAN”S FORECAST CASHFLOWS | NET PRESENT VALUE (US$M) OF EDIKAN”S FORECAST CASHFLOWS | NET PRESENT VALUE (US$M) OF EDIKAN”S FORECAST CASHFLOWS |
|---|---|---|---|
Discount Rate (%) |
Gold Price |
||
| US$1,100/oz | US$1,200/oz | US$1,300/oz | |
| 6.50 8.25 10.00 |
226 206 189 |
324 300 278 |
419 389 363 |
Comments from Perseus’s Managing Director, Jeff Quartermaine
The updated Life of Mine Plan clearly demonstrates that Edikan is an economically robust operation that has successfully come through an extended ramp up phase. Based on this updated plan, the future prospects of Edikan, and therefore Perseus, are both very positive.
Over the past twelve months we have demonstrated that by focussing on achieving incremental improvements to both the technical and commercial aspects of our operation, we can consistently deliver credible results.
The external environment in which we operate can be unpredictable and challenging at times, however, based on recent performance, we are very confident that we have a highly professional site team that is adaptable and more than capable of rising to these challenges when they occur.
We are very much looking forward to consistently delivering to this plan and in the process creating material value for our shareholders.
Perseus Mining Limited (ACN 106 808 986), Second Floor, 437 Roberts Road, Subiaco WA 6008, Australia PO Box 1578, Subiaco WA 6904, Australia T +618 6144 1700 | F +618 6144 2406
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1All in site cash costs include direct production costs, royalties, investment in waste stripping and sustaining capital expenditure. It does not include exploration expenditure, income taxes or corporate costs
Figure 1: Edikan Gold Mine layout
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MINERAL RESOURCES
An updated Mineral Resource estimate for EGM has been prepared by independent consultant, RungePincockMinarco (“RPM”) in accordance with the JORC Code – 2012 Edition. This estimate is based on the 1 May 2014 Mineral Resource estimate previously prepared by RPM that has been amended for mining depletion to 31 January 2015 in the case of the AF Gap and Fobinso pits. It has also been amended to include in-fill drilling results returned from a recent drilling campaign on the Mampong mineral deposit which amendment is immaterial to the total Edikan Resource.
In summary, the updated global Measured and Indicated Mineral Resource for EGM is now estimated as 149.5Mt grading 1.1g/t gold, containing 5.25 Mozs of gold. A further 68.1Mt of material grading 1.0g/t gold and containing a further 2.17 Mozs of gold are classified as Inferred Mineral Resources. Details of these estimates are shown below in Table 1.
SCENARIO PLANNING
Based on the revised Mineral Resource estimate, Perseus examined a range of development scenarios with the objective of maximising the net present value of forecast cash flows from EGM. This task involved varying key parameters such as the pit development sequence, applying technical assumptions that reflected actual operating parameters, and working within known constraints such as the expected timing of access to new mining areas. .
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Table 1: Mineral Resources[1,2] , Edikan Gold Mine
| Deposit | Measured Resources | Indicated Resources | Measured + Indicated Resources | Inferred Resources | |
|---|---|---|---|---|---|
| Quantity Grade Gold |
Quantity Grade Gold |
Quantity Grade Gold |
Quantity Grade Gold |
||
| Mt g/t gold Kozs |
Mt g/t gold Kozs |
Mt g/t gold Kozs |
Mt g/t gold Kozs |
||
| AAF Bokitsi Fetish Chirawewa Dadieso Esuajah North Esuajah South Mampong |
30.8 1.1 1,080 0.7 3.7 86 12.7 0.9 380 - - - - - - 16.9 0.9 494 9.5 1.8 546 0.2 0.9 6 |
23.8 0.9 680 1.6 2.6 133 18.1 1.2 663 5.8 1.1 195 - - - 18.4 0.8 493 7.3 1.6 370 3.7 1.0 122 |
54.6 1.0 1,760 2.3 2.9 219 30.8 1.1 1043 5.8 1.1 195 - - - 35.3 0.9 986 16.8 1.7 916 3.9 1.0 128 |
28.5 0.8 731 2.9 1.8 170 10.0 1.1 346 10.4 0.9 284 5.3 1.5 253 3.6 0.9 105 5.7 1.1 211 2.0 1.0 67 |
|
| Total | 70.8 1.1 2,591 |
78.7 1.0 2,654 |
149.5 1.1 5,246 |
68.1 1.0 2,165 |
Notes: 1. Last updated on 15 March 2015 allowing for mining depletion to 31 January 2015. 2. 0.4g/t gold cut-off applied.
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Based on this work, the pit development schedule as shown in Figure 2 below was developed
Figure 2 – Pit Development Schedule
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Pit Scheduling
Bokitsi - Stage 1
AG - Final
Esuajah S - Final
Esuajah S - Stage 1
Esuajah N - Final
Esuajah N - Stage 1
Fetish - Final
Chirawewa S - Final
Chirawewa N - Final
Fetish - Stage 1
Fobinso - Final
Fobinso - Stage 3
AG - Stage 2
AG - Stage 3
Feb 15 Feb 16 Jan 17 Jan 18 Jan 19 Jan 20 Jan 21 Jan 22
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ORE RESERVES
Based on the re-estimated EGM Mineral Resource, pit optimisation and scheduling, RPM independently calculated the Ore Reserves for the EGM as at 1 February 2015 in accordance with the requirements of the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (the JORC Code, 2012 Edition). (Refer to Appendix 1 for JORC 2012 Table 1)
In summary, the updated Proved and Probable Ore Reserve for EGM is now estimated as 61.6Mt grading 1.2g/t gold, containing 2.35 Mozs of gold including 44.2Mt of material grading 1.2g/t gold and containing a further 1.66 Mozs of gold in the Proved category and 17.3Mt of material grading 1.2g/t gold and containing a further 0.69Mozs of gold classified as Probable Ore Reserves. Details of these estimates are shown below in Table 2 .
The estimation of the Ore Reserves for Edikan was based on the following assumptions:
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Proven and Probable Ore Reserves are found within the economic limits of seven discrete open pits that have been designed based on Measured and Indicated Mineral Resources that incorporated all available Resource infill drilling results, a gold price of US$1,200/oz and mining, processing and general and administration costs derived from recent operating experience;
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The January 2015 Mineral Resource model has been re-blocked to reflect mining ore loss and dilution that is consistent with the historical reconciliations between the Resource model and grade control drilling (98% of contained gold) and between grade control drilling and the mill reconciliations (96% of contained gold);
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Economic assumptions
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a. Gold metal price US$1,200/oz.
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b. Un-escalated average costs used in optimising pit designs are as shown in Table 3 below.
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c. A discount rate of 10% (real) has been assumed to calculate net present values of forecast cash flows.
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Table 2: EGM Proved and Probable Ore Reserves as at 1 February 2015
| Deposit | Proved Reserves | Proved Reserves | Probable Reserve | Proved + Probable Reserves |
|---|---|---|---|---|
| Quantity Grade |
Gold | Quantity Grade Gold |
Quantity Grade Gold |
|
| Mt g/t gold |
Koz | Mt g/t gold Koz |
Mt g/t gold Kozs |
|
| AAF Fobinso Fetish Esuajah North Esuajah South Chirawewa Bokitsi Stockpile |
11.5 1.2 3.5 1.3 8.6 1.0 10.5 1.0 5.7 1.8 - - 0.8 3.3 3.6 0.6 |
449 146 268 326 319 - 80 72 |
1.6 0.8 42 0.2 1.1 8 8.6 1.4 381 3.5 0.9 105 0.9 1.8 53 2.4 1.2 95 0.1 2.8 7 - - - |
13.1 1.2 491 3.7 1.3 153 17.3 1.2 649 14.0 1.0 431 6.6 1.8 372 2.4 1.2 95 0.9 3.2 87 3.6 0.6 72 |
| Total | 44.2 1.2 |
1,659 | 17.3 1.2 690 |
61.6 1.2 2,349 |
Notes:
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Estimate has been rounded to reflect accuracy
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All the estimates are on a dry tonne basis
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Based on March 2015 Mineral Resource estimation
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Variable gold cut-off grade based on material type
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Inferred Mineral Resource is treated as mineralised waste
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Calculated in March 2015 and allows for mining depletion up to and including 31 January 2015
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The boundary between Ore Reserves included in the Fetish and Bokitsi pits has been modified since calculation of the July 2014 Ore Reserve. The northern portion of the mineralised material that was previously to be mined in the Bokitsi pit will now mined in the Fetish Pit.
Table 3: Assumed operating costs
| Mining | Processing | G&A | Selling | Royalties |
|---|---|---|---|---|
| US$3.33/t mined | US$9.03/t milled | US$2.48/t milled | US$0.04/oz sold | 6.75% |
4. Mining parameters
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a. The chosen method of mining is conventional open pit mining utilising hydraulic excavators and trucks, mining bench heights of 5 m with 2.5m flitches to minimise ore loss and waste rock dilution.
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b. The economic pit shell was defined using Whittle 4X pit optimisation software (“Whittle 4X”) with inputs such as geotechnical parameters, ore loss and dilution, metallurgical recovery and mining costs.
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c. The pit optimisation was run with revenue generated only by Measured and Indicated Mineral Resources. No value was allocated to Inferred Mineral Resources.
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d. Whittle 4X input parameters were generally based on Perseus’s operating site experience and supporting technical studies.
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e. The pit slope design assumptions are based on a geotechnical study by George, Orr and Associates (Australia) Pty Ltd. Overall pit slopes are 30 to 50 degrees inclusive of berms spaced at between 5 and 20m vertically and berm widths of 5 to 12 m.
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f. Pit ramps have been designed for a 777 truck fleet and are set at a net 16m (single lane) to 26m (dual lane).
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g. Vertical mining advance has been set at a maximum of 90m/year based on historical performance and operational improvements.
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h. Appropriate mining modifying factors such as ore loss, dilution and design parameters were used to convert the Mineral Resource to an Ore Reserve.
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i. Mining dilution varies by deposit as a result of block regularisation resulting in a range, due to multiple block models used, between 3-12%.
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j. Minimum mining width of 40 m was generally applied to the pit designs.
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k. As the mine has been in operation and the mining method is not changed, no major infrastructure is required due to the selected mining method other than that required to provide access to the Eastern and Northern mining areas.
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l. There are no physical constraints to mining within the lease area. No property, infrastructure or environmental issues are known to exist which may limit the extent of mining within the mining lease.
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m. Ore cut-off grades are based on the gold price, cost and mining parameters described in paragraphs 3, and 4(a) to (l) above and are as shown in Table 4 as follows:
Table 4: Cut-off Grades
| Deposit | **Cut-Off Grade by Ore Type ** | **Cut-Off Grade by Ore Type ** | (g/tgold) |
|---|---|---|---|
| Oxide | Transition | Fresh Granite | |
| AF Gap Fobinso Fetish Bokitsi Chirawewa Esuajah North Esuajah South |
0.35 0.60 0.45 0.45 0.45 0.45 0.45 |
0.50 0.50 0.60 0.60 0.60 0.60 0.60 |
0.45 0.40 0.55 0.50 0.50 0.50 0.50 |
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n. Due to a reduction in contract mining costs, the push back of the AG Final pit wall will now extend to surface at the Stage 3 end of the AG pit and will take out most of the area of wall instability that has occurred on the southern side of the AG Stage 3 Pit.
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o. Mining is scheduled to commence in the Eastern pits (including Fetish, Bokitsi and Chirawewa) in April 2015. As at the date of this release, the Ghanaian Environmental Protection Agency had not approved the Supplementary Environmental Impact Statement, a pre-requisite for the commencement of mining activities.
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Processing parameters
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a. The process metallurgical recovery for gold is fixed by material type in each deposit. Gold recovery rates range from 57-61% for oxide ore and 82-94% for primary ore. Recovery variation is a function of differing metallurgical properties of ores from different deposits and recoveries by pit are as shown in Table 5 .
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b. No deleterious material has been identified.
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c. Average annual processing throughput rate of ore from all pits of 7.0Mtpa. The processing circuit involves single stage crushing, semi-autogenous grinding, gravity recovery, flotation, regrind and CIL.
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d. A secondary crusher is planned to be installed and available for use by March 2016, at a capital cost of US$15 million.
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e. Allowance has been made in the calculation of ore processing rates for the 33% decrease in plant availability in the months of February to April 2015 as a result of government imposed power restrictions. Beyond April 2015, an amount of power will be generated on site using diesel generators and this will supplement power from the grid and restore the availability of full power to the site.
Table 5: Recoveries
| Deposit | Recovery by | Ore Type (%) | ||
|---|---|---|---|---|
| Oxide | Transition | Fresh Granite | Fresh Sediment | |
| AF Gap Fobinso Fetish Bokitsi Chirawewa Esuajah North Esuajah South |
61.0 61.0 61.0 56.7 59.5 61.0 61.0 |
73.4 73.4 73.4 69.0 72.0 73.4 73.4 |
88.0 88.0 91.0 82.0 86.0 93.0 94.0 |
- - 90.0 - - 87.0 - |
6. Classification
Ore Reserves have been classified based on the underlying Mineral Resources classifications and the level of detail in the mine planning. The Mineral Resources were classified as Measured, Indicated and Inferred. The Ore Reserves, based only on the Measured and Indicated Resources, have been classified as Proven and Probable Ore Reserves, respectively.
The Ore Reserve is classified as Proved and Probable in accordance with the JORC Code, corresponding to the Mineral Resource classifications of Measured and Indicated and taking into account other factors where relevant. The deposit’s geological model is well constrained. The Ore Reserve classification is considered appropriate given the nature of the deposit, the moderate grade variability, drilling density, structural complexity and mining history. Therefore it was deemed appropriate to use Measured Mineral Resources as a basis for Proven Reserves and Indicated Mineral Resources as a basis for Probable Reserves.
No Inferred Mineral Resources were included in the Ore Reserve estimate.
UPDATED LIFE OF MINE PLAN
Based on the Ore Reserves stated above, the updated life of mine production profile for the EGM is forecast as shown in Table 6 below. In summary, in the eight years of production between FY2016 and FY2023 inclusive, annual gold production will average approximately 235,000ozs at weighted average all-in site cost of US$937/oz.
Compared to the October 2013 LOMP (adjusted for mining depletion to 31 January 2015), the updated LOMP results in the following changes to physical parameters:
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Tonnes of ore and waste moved - Up by 4%
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• Tonnes of Ore - Down by 18% • Life of mine strip ratio - Up by 1.3 to 4.0 • Head grade - Up by 8% • Contained gold in Ore Reserve - Down by 10% • Life of mine - Reduced by 14 months to July 2023
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The forecast unit all-in site cash costs for the EGM’s LOMP are also as shown in Table 6 below. It should be noted that these costs differ marginally from the input costs used in the calculation of the Ore Reserve and reflect actual cost reductions achieved plus cost reductions expected to be realised from recently implemented initiatives at the EGM in the period between the commencement of calculation of Ore Reserves and finalisation of pit optimisations. These estimated unit costs are based on the following assumptions:
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The weighted average un-escalated life of mine mining cost assumed in the LOMP is US$3.33/t of material moved. Mining costs include the cash cost of mining both ore and waste (including all waste stripping costs) during the period. The weighted average mining cost is based on the following:
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a. AG Pit – For Stages 2 and 3 of the pit, costs are contracted rates negotiated in November 2009 with mining contractor, African Mining Services (Ghana) Pty Ltd (“AMS”), adjusted for historical rise and fall factors. The costs for mining the Final Stage of the AG Pit are based on recently negotiated rates for mining the Final Stage of the Fobinso Pit.
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b. Fobinso Pit – un-escalated contracted rates negotiated in September 2014 with mining contractor Rocksure International.
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c. Fetish, Bokitsi, and Chirawewa (the “Eastern Pits”) - un-escalated contracted rates for mining the negotiated in March 2015 with mining contractor, AMS.
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d. Esuajah North and Esuajah South - mining rates are based on recently negotiated rates for minng the Eastern Pits.
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Un-escalated unit processing costs are assumed to be US$9.03/t of ore processed plus a further US$0.04/t of ore processed for bullion transport and refining costs.
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An un-escalated General and Administration unit cost of US$2.48/t of ore processed has been assumed for the remaining years of the mine.
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Royalty is based on a US$1,200/oz gold price and assumes a 5% royalty paid to the Ghanaian government, a 1.5% royalty payable to Franco Nevada and a 0.25% royalty payable to Waratah Investments Ltd.
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Sustaining capital expenditure is estimated at US$108 million (un-escalated) over the remaining life of mine. (Refer to Table 6 below for details).
The largest items of forecast capital expenditure relate to the total costs of gaining access to areas for mining within the existing Mining Lease boundary. Under Ghanaian laws, Perseus is required to compensate landowners for loss of crops, structures and livelihood as well as provide alternative housing built to the rigorous building standards specified in relevant legislation. In addition, where infrastructure such as roads is located within a blast radius of 500 metres from a planned open pit, the infrastructure needs to be relocated. In the case of the Esuajah South pit, this involves the relocation of several roads as well as a number of dwellings. In total, access costs accounts for approximately 64 percent of the total estimated sustaining capital required to be spent during the remaining 8-9 years of mine life.
The use of underground mining techniques to mine the Esuajah South Mineral Resource (and therefore minimise disruption to existing land use and the need for housing and infrastructure relocation) has been investigated, however, this is not an economic proposition at the currently assumed gold price. Notwithstanding the relatively high estimated cost of gaining access to the Esuajah South mine area, the economics of developing an open pit mining operation and processing the ore are incrementally positive, and therefore development of this pit has been included in the LOMP schedule. Further investigation of underground mining options is being considered.
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Table 6: LOMP Production and Costs
| Parameter | FY2016 | FY2017 FY2018 |
FY2019 | FY2020 | FY2021 | FY2022 | FY2023 FY2024 |
Total |
|---|---|---|---|---|---|---|---|---|
| PRODUCTION Ore mined Mt 5.4 Waste mined Mt 27.2 Total Material Mined Mt 32.6 Strip ratio t:t 5.0 Unit mining costs US$/t mined 3.26 Ore processed Mt 7.3 Head grade g/t gold 1.1 Recovery % 85.0 Gold production kozs 208 COSTS Unit mining costs US$/t mined 3.26 Unit processing costs US$/t milled 8.99 Unit G&A costs US$/t milled 2.66 Production cash costs1 US$/oz 916 Royalties US$/oz 88 Sustaining capital costs2 US$/oz 158 Total all-in site cash cost US$/oz 1,162 1Includes mining (incl. all waste stripping), processing, general and 2Sustaining capital includes: Access* to all mining areas US$M 10.616 Mining infrastructure US$M 3.925 Processing infrastructure US$M 17.850 G&A sustaining US$M 0.500 Reclamation & Closure US$M 0.000 Total sustaining capital US$M 32.891** |
6.8 10.7 39.1 41.4 45.9 52.1 5.8 3.9 3.00 3.31 7.2 7.3 1.1 1.2 89.2 90.5 222 245 3.00 3.31 8.95 8.99 2.66 2.64 998 1,048 82 81 74 192 1,155 1,321 administration cash costs 14.057 45.204 0.000 0.000 1.956 1.374 0.500 0.500 0.000 0.000 16.513 47.078 |
10.4 48.4 58.8 4.7 3.14 7.1 1.3 91.1 275 3.14 9.02 2.70 973 81 7 1,062 0.000 0.000 1.535 0.500 0.000 2.035 |
7.1 37.2 44.3 5.2 3.37 6.9 1.6 89.7 312 3.37 9.37 2.79 745 81 7 833 0.000 0.500 0.750 0.500 0.466 2.216 |
6.8 21.6 28.4 3.2 3.57 6.8 1.3 90.2 258 3.57 9.35 2.84 711 81 2 795 0.000 0.000 0.100 0.500 0.031 0.631 |
6.2 5.5 11.7 0.9 4.37 6.8 1.4 91.1 286 4.37 9.41 2.12 453 81 11 545 0.000 0.000 0.100 0.000 3.156 3.256 |
0.4 - 0.1 - 0.5 - 0.3 - 6.26 - 6.8 0.5 0.7 0.7 90.3 80.2 129 9 6.26 - 8.33 7.63 1.36 0.65 531 485 81 81 1 404 613 970 0.000 0.000 0.000 0.000 0.100 0.100 0.000 0.000 0.000 3.498 0.100 3.598 |
53.8 220.5 274.3 4.1 3.30 56.7 1.2 89.7 1,944 3.33 9.04 2.48 800 82 56 937 69.877 4.425 23.865 3.00 7.151 108.318 |
*Access costs include the cost of all forms of compensation to be paid to landholders, acquisition of land for relocation housing, and development costs for relocation housing including civil works, house construction and project management
** Excludes cost of transporting and refining bullion at $0.04/oz
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The sustaining capital cost estimate includes the cost of site rehabilitation net of equipment salvage value in the final year of the mine.
It is intended that the EGM LOMP will be reassessed annually taking into account any incremental Mineral Resources delineated during the preceding period and any revisions to design parameters (including, but not limited to, gold price and operating costs) in the design of the pit shells.
FY2015 PRODUCTION AND COST GUIDANCE
The updated LOMP has confirmed that the current FY2015 production and cost guidance shown remains unchanged and is below in Table 7 .
Table 7: FY 2015 Revised Production and Cost Guidance
| Parameter | Units | December 2014 **Half Year1 ** |
June 2015 Half Year |
FY2015 |
|---|---|---|---|---|
| Gold Production All-In Site Cash Costs |
Ounces US$/oz |
100,016 988 |
100,000-110,000 1,150-1,250 |
200,000-210,000 1,075-1,125 |
1Actual production and costs
INVESTMENT METRICS
Based on the life of mine production and cost parameters, the investment metrics as expressed by the Net Present Value of cash flows forecast to be generated by the Edikan Mine at a range of gold prices and applying a range of real discount rates are as follows:
| NET PRESENT VALUE (US$M) OF EDIKAN”S FORECAST CASHFLOWS | NET PRESENT VALUE (US$M) OF EDIKAN”S FORECAST CASHFLOWS | NET PRESENT VALUE (US$M) OF EDIKAN”S FORECAST CASHFLOWS | NET PRESENT VALUE (US$M) OF EDIKAN”S FORECAST CASHFLOWS |
|---|---|---|---|
| Real Discount Rate (%) |
Gold Price | ||
| US$1,100/oz | US$1,200/oz | US$1,300/oz | |
| 6.50 8.25 10.00 |
226 206 189 |
324 300 278 |
419 389 363 |
Jeffrey A Quartermaine Managing Director and Chief Executive Officer 20 April 2015
To discuss any aspect of this announcement, please contact:
Managing Director: Jeff Quartermaine at telephone +61 8 6144 1700 or email [email protected] (Perth);
Investor Relations: Nathan Ryan at telephone +61 (0) 420 582 887 or email [email protected] (Melbourne); or
Caution Regarding Forward Looking Information :
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This report contains forward-looking information which is based on the assumptions, estimates, analysis and opinions of management made in light of its experience and its perception of trends, current conditions and expected developments, as well as other factors that management of the Company believes to be relevant and reasonable in the circumstances at the date that such statements are made, but which may prove to be incorrect. Assumptions have been made by the Company regarding, among other things: the price of gold, continuing commercial production at the Edikan Gold Mine without any major disruption, development of a mine at Tengrela, the receipt of required governmental approvals, the accuracy of capital and operating cost estimates, the ability of the Company to operate in a safe, efficient and effective manner and the ability of the Company to obtain financing as and when required and on reasonable terms. Readers are cautioned that the foregoing list is not exhaustive of all factors and assumptions which may have been used by the Company. Although management believes that the assumptions made by the Company and the expectations represented by such information are reasonable, there can be no assurance that the forward-looking information will prove to be accurate. Forward-looking information involves known and unknown risks, uncertainties, and other factors which may cause the actual results, performance or achievements of the Company to be materially different from any anticipated future results, performance or achievements expressed or implied by such forward-looking information. Such factors include, among others, the actual market price of gold, the actual results of current exploration, the actual results of future exploration, changes in project parameters as plans continue to be evaluated, as well as those factors disclosed in the Company's publicly filed documents. The Company believes that the assumptions and expectations reflected in the forward-looking information are reasonable. Assumptions have been made regarding, among other things, the Company’s ability to carry on its exploration and development activities, the timely receipt of required approvals, the price of gold, the ability of the Company to operate in a safe, efficient and effective manner and the ability of the Company to obtain financing as and when required and on reasonable terms. Readers should not place undue reliance on forward-looking information. Perseus does not undertake to update any forward-looking information, except in accordance with applicable securities laws.
Competent Person Statement
All production targets for the Edikan Gold Mine (EGM) referred to in this report are underpinned by estimated Ore Reserves which have been prepared by competent persons in accordance with the requirements of the JORC Code.
The information in this report that relates to Mineral Resources for the Fetish, Bokitsi, Chirawewa, Esuajah North, Esuajah South and Dadieso deposits and to Exploration Results and Sampling for the AFGap-Fobinso deposit was first reported by the Company in compliance with the JORC Code 2012 in market announcements released on 27 August 2014 and 4 September 2014. The Company confirms that it is not aware of any new information or data that materially affects the information in those market announcements.
The information in this report and the attachments that relates to Mineral Resources for the AFGap-Fobinso deposit is based on information compiled by Graham de la Mare under the supervision of Paul Payne a Competent Person who is a Member of the Australasian Institute of Mining and Metallurgy, and an Associate Consultant to RungePincockMinarco. Mr Payne has sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activity which he has undertaken to qualify as a Competent Person as defined in the JORC Code 2012.Mr Payne has no economic, financial or pecuniary interest in the company and consents to the inclusion in this report of the matters based on his information in the form and context in which it appears.
The information in this report that relates to Mineral Resources for the Mampong deposit is based on information compiled by Steffen Brammer under the supervision of Graham de la Mare a Competent Person who is a Member of the Australian Institute of Geoscientists, and a full time employee of RungePincockMinarco. Mr de la Mare has sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activity which he has undertaken to qualify as a Competent Person as defined in the JORC Code 2012.Mr de la Mare has no economic, financial or pecuniary interest in the company and consents to the inclusion in this report of the matters based on his information in the form and context in which it appears.
The information in this report and the attachments that relates to EGM Ore Reserves is based on information compiled and reviewed by Joe McDiarmid a Competent Person who is a Chartered Professional Member of the Australasian Institute of Mining and Metallurgy, and a full time employee of RungePincockMinarco. Mr McDiarmid has sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activity which he has undertaken to qualify as a Competent Person as defined in the JORC Code 2012.Mr McDiarmid has no economic, financial or pecuniary interest in the company and consents to the inclusion in this report of the matters based on his information in the form and context in which it appears.
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Appendix 1
JORC 2012 Compliant Table 1[1]
Section 1 Sampling Techniques and Data
| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Sampling techniques |
Nature and quality of sampling (eg cut channels, random chips, or specific specialised industry standard measurement tools appropriate to the minerals under investigation, such as down hole gamma sondes, or handheld XRF instruments, etc). These examples should not be taken as limiting the broad meaning of sampling. Include reference to measures taken to ensure sample representivity and the appropriate calibration of any measurement tools or systems used. Aspects of the determination of mineralisation that are Material to the Public Report. In cases where ‘industry standard’ work has been done this would be relatively simple (eg ‘reverse circulation drilling was used to obtain 1 m samples from which 3 kg was pulverised to produce a 30 g charge for fire assay’). In other cases more explanation may be required, such as where there is coarse gold that has inherent sampling problems. Unusual commodities or mineralisation types (eg submarine nodules) may warrant disclosure of detailed information. |
AAF Drill holes included in the Mineral Resource were sampled using close spaced Grade Control (GC) drilling on a nominal 8m to 10m grid, and Reverse Circulation (RC), and diamond drill (DD) holes on a nominal 20m by 40m grid spacing. A total of 4,890 holes were included in the resource for a total 134,341m within the resource wireframes. Holes were generally angled at 60° towards grid south to optimally intersect the mineralised zones. Grade control holes were drilled vertically. Drill hole collars were picked up and down hole surveyed by licensed surveyors. RC samples were collected by a riffle splitter at 1m intervals. Diamond core was cut in half using a core saw with sampling at 1m intervals, locally to geological boundaries. All samples were collected from the same side of the core. Sampling and QAQC procedures were carried out to industry standards. Approximately 6% of all RC samples were sent to ALS Minerals at Kumasi/Ghana for 24hr bottle roll with AAS finish. All other RC samples were analysed by 50g Fire Assay and AAS finish. Diamond half core samples were sent to Intertek Laboratories (Gh) Ltd at Tarkwa/Ghana for 50g Fire Assay and AAS finish. Fetish Samples at Fetish were collected using drilling techniques such as Reverse Circulation (RC) and Diamond Drilling (DD). Holes were generally angled at between 45° and 60° towards grid west or east to optimally intersect the mineralised zones. Some RC drill holes have diamond tails. RC samples were collected as 4m composites until potential mineralisation was expected at which time samples were collected at 1m intervals from a rig mounted cyclone into large numbered plastic bags. Recently, PRU drilling has used 2m composite samples, and then 1m samples through potential mineralisation. |
1 The commentary included applies to all deposits included in the Reserve estimate except where explicitly stated that commentary only applies to a specific deposit or specific deposits.
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Diamond core was generally sampled at even 1m intervals. Sampling and QAQC procedures were carried out to industry standards. Rig mounted riffle splitters were used to split RC samples and minimise bias. Diamond core was cut in half using a diamond saw and the right hand side of the core was always submitted for analysis with the left side being stored in trays on site. Approximately 5% of all RC samples were sent to the Intertek (formerly TWL) laboratory for 24hr bottle roll with AAS finish. All other RC samples and Diamond half core were analysed by 50g Fire Assay and AAS finish. Samples were sent to Intertek Laboratories (Gh) Ltd at Tarkwa/Ghana (24%), ALS (35%), TWL (18%), and SGS laboratories (2%). Bokitsi Samples at Bokitsi were collected using drilling techniques such as Reverse Circulation (RC) and Diamond Drilling (DD). Holes were generally angled at between 45° and 60° towards grid west to optimally intersect the mineralised zones. Some RC drill holes have diamond tails. RC samples were collected as 4m composites until potential mineralisation was expected at which time samples were collected at 1m intervals from a rig mounted cyclone into large numbered plastic bags. Recent PRU drilling has used 2m composite samples, and then 1m samples through potential mineralisation. Diamond core was generally sampled at even 1m intervals. Sampling and QAQC procedures were carried out to industry standards. Rig mounted riffle splitters were used to split RC samples and minimise bias. Diamond core was cut in half using a diamond saw and the right hand side of the core was always submitted for analysis with the left side being stored in trays on site. Approximately 5% of all RC samples were sent to the Intertek (formerly TWL) laboratory for 24hr bottle roll with AAS finish. All other RC samples and Diamond half core were analysed by 50g Fire Assay and AAS finish. Samples were sent to Intertek Laboratories (Gh) Ltd at Tarkwa/Ghana (24%), ALS (35%), TWL (18%), and SGS laboratories (2%). Chirawewa Samples at Chirawewa were collected using drilling techniques such as Reverse Circulation (RC) and Diamond Drilling (DD). Holes were generally angled at 60° towards grid west or east to optimally intersect the mineralised zones. Some RC drill holes have diamond tails. Historical RC samples were collected as 4m composites until potential mineralisation was expected at which time samples were collected |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| at 1m intervals from a rig mounted cyclone into large numbered plastic bags. Recent PRU drilling has used 2m composite samples, and then 1m samples through potential mineralisation. Diamond core was generally sampled at even 1m intervals. Sampling and QAQC procedures were carried out to industry standards. Rig mounted riffle splitters were used to split RC samples and minimize bias. Diamond core was cut in half using a diamond saw and the right hand side of the core was always submitted for analysis with the left side being stored in trays on site. Approximately 5% of all RC samples were sent to the Intertek (formerly TWL) laboratory for 24hr bottle roll with AAS finish. All other RC samples and Diamond half core were analysed by 50g Fire Assay and AAS finish. Samples were sent to Intertek Laboratories (Gh) Ltd at Tarkwa/Ghana (24%), ALS (35%), TWL (18%), and SGS laboratories (2%). Historical sampling and assaying methods are unknown and represent 22% of the supplied assay data. Esuajah North Drill holes included in the resource were sampled using Reverse Circulation (RC) and diamond drill (DD) holes on a nominal 40m by 40m grid spacing (with localised areas of 20m by 20m). A total of 160 holes were included in the resource for a total 3,295m within the resource wireframes. Holes were generally angled at 50° towards grid west or east to optimally intersect the mineralised zones. Drill hole collars were picked up and down hole surveyed by qualified surveyors. RC samples were collected by a riffle splitter at 1m to 2m intervals. Diamond core was cut in half using a core saw with sampling at geological boundaries. All samples were collected from the same side of the core. Sampling and QAQC procedures were carried out to industry standards. Samples from the first 60 RC drill holes were sent to Transworld Laboratory for 24hr bottle roll with AAS finish. All subsequent RC samples were analysed by 50g Fire Assay at ALS Kumasi. Diamond half core samples analysed by 50g Fire Assay and AAS finish. Esuajah South Drill holes included in the resource were sampled using Reverse Circulation (RC) and diamond drill (DD) holes on a nominal 20m by 20m grid spacing. A total of 151 holes were included in the resource for a total 13,503m within the resource wireframes. Holes were generally angled at 50° towards grid west or east to optimally intersect the mineralised zones. Drill hole collars werepicked upand down hole |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| surveyed by qualified surveyors. RC samples were collected by a riffle splitter at 1m intervals. Diamond core was cut in half using a core saw with sampling at geological boundaries. All samples were collected from the same side of the core. Sampling and QAQC procedures were carried out to industry standards. RC samples sent to Transworld Laboratory for 24hr bottle roll with AAS finish. Diamond half core samples analysed by 50g Fire Assay and AAS finish. |
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| Drilling techniques |
Drill type (eg core, reverse circulation, open-hole hammer, rotary air blast, auger, Bangka, sonic, etc) and details (eg core diameter, triple or standard tube, depth of diamond tails, face- sampling bit or other type, whether core is oriented and if so, by what method, etc). |
RC drilling comprising 105mm diameter face sampling bit. Diamond drilling carried out with HQ2 and NQ2 sized equipment. |
| Drill sample recovery |
Method of recording and assessing core and chip sample recoveries and results assessed. Measures taken to maximise sample recovery and ensure representative nature of the samples. Whether a relationship exists between sample recovery and grade and whether sample bias may have occurred due to preferential loss/gain of fine/coarse material. |
Recoveries from historical drilling are unknown. Actual recoveries from PRU diamond drilling recorded in the database and averaged as follows for each deposit with no significant issues noted: oAAF: 95.5% oFetish: 93% oBokitsi: 93% oChirawewa: 93% oEsuajah North: 96% oEsuajah South: 96.7% RC samples were visually checked for recovery, moisture and contamination. No relationship exists between sample recovery and grade. |
| Logging | Whether core and chip samples have been geologically and geotechnically logged to a level of detail to support appropriate Mineral Resource estimation, mining studies and metallurgical studies. Whether logging is qualitative or quantitative in nature. Core (or costean, channel, etc) photography. The total length and percentage of the relevant intersections logged. |
All holes were field logged by company geologists. Weathering, lithology, alteration, structure, mineralogy and veining information were recorded. RC chips are glued to boards as a visual reference of every hole. Logging of diamond core additionally recorded recovery, core strength, orientation, roughness, and infill type. Diamond core was photographed. All drill holes were logged in full. Logging was qualitative and quantitative in nature. |
| Sub-sampling techniques and sample preparation |
If core, whether cut or sawn and whether quarter, half or all core taken. If non-core, whether riffled, tube sampled, rotary split, etc and whether sampled wet or dry. |
HQ2 and NQ2 core was cut in half using a core saw. All samples were collected from the same side of the core. RC samples were collected at the rig using riffle splitters. AAF, Fetish, Bokitsi, Chirawewa and |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| For all sample types, the nature, quality and appropriateness of the sample preparation technique. Quality control procedures adopted for all sub- sampling stages to maximise representivity of samples. Measures taken to ensure that the sampling is representative of the in situ material collected, including for instance results for field duplicate/second-half sampling. Whether sample sizes are appropriate to the grain size of the material being sampled. |
Esuajah North samples were predominantly dry. Esuajah South samples were predominantly wet but very few occur within the Mineral Resource wireframes. For AAF 1% of samples were recorded as wet in the supplied database in the ‘sampquality’ field and were removed from the resource composites. For Esuajah North less than 0.5% of samples were recorded as ‘wet’ in the supplied data in the ‘sampquality’ field, although 55% of records in this field are blank. Sampling of diamond core and RC chips uses industry standard techniques. After drying the sample is subject to a primary crush, then pulverised so that 90% passes a -75um sieve. Field QC procedures involved the use of certified reference materials (1 in 20), and field duplicates (1 in 20). Field duplicates were taken on 1m to 2m composites for RC using a riffle splitter. Sample sizes are considered appropriate to correctly represent the moderately nuggetty gold mineralisation based on: the style of mineralisation, the thickness and consistency of the intersections, the sampling methodology and assay value ranges for Au. |
|
| Quality of assay data and laboratory tests |
The nature, quality and appropriateness of the assaying and laboratory procedures used and whether the technique is considered partial or total. For geophysical tools, spectrometers, handheld XRF instruments, etc, the parameters used in determining the analysis including instrument make and model, reading times, calibrations factors applied and their derivation, etc. Nature of quality control procedures adopted (eg standards, blanks, duplicates, external laboratory checks) and whether acceptable levels of accuracy (ie lack of bias) and precision have been established. |
The analytical techniques used Fire Assay on 50g samples or BLEG bottle roll on 1kg samples both with AAS finish. This method approaches total dissolution of most minerals. No geophysical tools were used to determine any element concentrations used in the resource estimate. Sample preparation checks for fineness were carried out by the laboratory as part of internal procedures to ensure the grind size of 90% passing 75µm was being attained. Laboratory QAQC includes the use of internal standards using certified reference material, and pulp replicates. Certified reference materials demonstrate that sample assay values are accurate. The QAQC results confirm the suitability of the drilling data for use in the Mineral Resource estimation. |
| Verification of sampling and assaying |
The verification of significant intersections by either independent or alternative company personnel. |
The PRU logging process involves placing RC drill samples for each 1m interval onto a board to form a visual log of the entire hole. PRU senior exploration personnel verified the significant intersections by comparing the returned assay results to the photographs of the ‘chip boards’. RPM has not independently verified significant intersections of mineralisation. |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| The use of twinned holes. Documentation of primary data, data entry procedures, data verification, data storage (physical and electronic) protocols. Discuss any adjustment to assay data. |
For AAF a total of 4 RC holes have been twinned by DD to test down hole contamination in wet intervals. Twinned holes have not been drilled for Fetish, Bokitsi and Chirawewa. The same applies to Esuajah South althouth the east and west dipping holes on 20m spacing result in ‘crossing’ of drill traces at depth. For Esuajah North DKRC067 and DKRC068 are twinned holes and display similar down hole grades. The east and west dipping holes on 40m spacing result in ‘crossing’ of drill traces at depth. Primary data is entered on hard copies in the field, then entered digitally using LogChiefSoftware (Maxwell GeoServices). This data is directly imported into the central Datashed database (Maxwell GeoServices). Assay values that were below detection limit were adjusted to equal half of the detection limit value. Intervals with no samples were left blank in the database (updated from the -9 value used by PRU). |
|
| Location of data points |
Accuracy and quality of surveys used to locate drill holes (collar and down-hole surveys), trenches, mine workings and other locations used in Mineral Resource estimation. Specification of the grid system used. |
Prior to 2012, a local grid, including baseline, was established at Edikan by Cluff Plc using licensed surveyors. Licensed surveyors were used to locate all drill collars in local grid co- ordinates. The majority of PRU drill holes are surveyed down hole at 10m to 30m intervals using either Reflex or Flexit multi-shot equipment. Historical RC holes have not been down hole surveyed and are assumed to be straight. Historical diamond holes were down hole surveyed using either acid tubes or a single shot camera. For recent drill programs, collars have been located in UTM, WGS84, Zone 30N co-ordinates and transformed to local grid. True azimuths were converted to local by subtracting 43 from the true value. Local RL elevations were adjusted by adding 1,000m to avoid negative values. This was not done for the previous Mineral Resource estimates. Topographic surface is based on survey points of |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Quality and adequacy of topographic control. |
the current pit surveyed during mining for AAF and existing open pits and drill collars for Fetish, Bokitsi and Chirawewa and merged with the regional 2010 topographic surface. The quality of the surface immediately above the mineralised lodes has been surveyed with a high degree of confidence by PRU Surveyors. For Esuajah North topographic surface is based on 1,181 historic pit survey points and 1,955 topographic and drill hole surveyed locations by PRU surveyors. For Esuajah South topographic surface is based on 1,407 survey points of the old pit surveyed during mining of the pit. A further 630 points were surveyed includingall drill collars,byPRU surveyors. |
|
| Data spacing and distribution |
Data spacing for reporting of Exploration Results. Whether the data spacing and distribution is sufficient to establish the degree of geological and grade continuity appropriate for the Mineral Resource and Ore Reserve estimation procedure(s) and classifications applied. Whether sample compositing has been applied. |
AAF The nominal resource drill hole spacing is 20m by 20m. Grade control holes are spaced at 8m by 8m or at 10m by 10m. The mineralised domains have demonstrated sufficient continuity in both geological and grade continuity to support the definition of Mineral Resource, and the classifications applied under the 2012 JORC Code. Samples have been composited to 2m lengths using best fit techniques. Residual sample lengths were excluded. Fetish The nominal drill hole spacing is 20m by 20m. The drill hole spacing and distribution is considered sufficient to establish the degree of continuity appropriate for the Mineral Resource estimation procedures. Samples were composited to 4m in zones previously identified as barren, otherwise composites at 2m intervals with 1m sampling intervals through expected mineralised zones. Bokitsi The nominal drill hole spacing is 20m by 20m and 40m by 40m. The drill hole spacing and distribution is considered sufficient to establish the degree of continuity appropriate for the Mineral Resource estimation procedures. Samples were composited to 4m intervals through zones previously identified as barren, otherwise 2m composites were collected with 1m sampling intervals through expected mineralised zones. Chirawewa The nominal resource drill hole spacing is 20m by 20m. The drill hole spacing and distribution is considered sufficient to establish the degree of continuity appropriate for the Mineral Resource estimation procedures. Samples have been composited to 4m or 2m intervals with 1m sampling intervals through expected mineralised zones. |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Esuajah North The nominal drill hole spacing is 40m by 40m. The mineralised domains have demonstrated sufficient continuity in both geological and grade continuity to support the definition of Mineral Resource, and the classifications applied under the 2012 JORC Code. Samples have been composited to 2m lengths using best fit techniques. One residual sample length was excluded. Esuajah South The nominal drill hole spacing is 20m by 20m. The mineralised domains have demonstrated sufficient continuity in both geological and grade continuity to support the definition of Mineral Resource, and the classifications applied under the 2012 JORC Code. Samples have been composited to 1m lengths using best fit techniques. Two residual sample lengths were excluded. |
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| Orientation of data in relation to geological structure |
Whether the orientation of sampling achieves unbiased sampling of possible structures and the extent to which this is known, considering the deposit type. If the relationship between the drilling orientation and the orientation of key mineralised structures is considered to have introduced a sampling bias, this should be assessed and reported if material. |
AAF Drill holes are angled to grid north or south, which is approximately perpendicular to the orientation of the mineralised trends. No orientation based sampling bias has been identified in the data. Fetish Drill holes are angled to grid north or south, which is approximately perpendicular to the orientation of the mineralised trends. No orientation based sampling bias has been identified in the data. Bokitsi Drill holes are angled to predominantly grid west, which is approximately perpendicular to the orientation of the mineralised trends. Historical AGC holes orientated to grid east. Due to the orientation of drill holes to the east or west, several holes have been drilled down dip within an east dipping sediment lode. Adjacent drill holes orientated to the west have shown that sampling bias from those two holes is not a significant issue. East dipping holes were excluded from the estimate. Chirawewa Drill holes are angled to grid west or east, which is approximately perpendicular to the orientation of the mineralised trends. Due to the orientation of drill holes to the east or west, two holes have been drilled down dip within an east dipping sediment lode. Adjacent drill holes orientated to the west have shown that sampling bias from those two holes is not a significant issue. |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Esuajah North Drill holes are angled to grid east and west, which is approximately perpendicular to the orientation of the interpreted mineralised trends. No orientation based sampling bias has been identified in the data. Esuajah South Drill holes are angled to grid east and west, which is approximately perpendicular to the orientation of the mineralised trends. No orientation based sampling bias has been identified in the data. |
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| Sample security | The measures taken to ensure sample security. |
Chain of custody is managed by PRU. Samples are stored on site and collected by laboratory employees. PRU employees have no further involvement in the preparation or analysis of the samples. |
| Audits or reviews |
The results of any audits or reviews of sampling techniques and data. |
A review of sampling techniques was carried out on each site visit by RPM, the most recent in 2010. |
Section 2 Reporting of Exploration Results
| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Mineral tenement and land tenure status |
Type, reference name/number, location and ownership including agreements or material issues with third parties such as joint ventures, partnerships, overriding royalties, native title interests, historical sites, wilderness or national park and environmental settings. The security of the tenure held at the time of reporting along with any known impediments to obtaining a license to operate in the area. |
The deposits are is located within the Nanankaw and Ayanfuri Mining Leases ML1110/1994 which are wholly owned by PRU. The tenements are in good standing. |
| Exploration done by other parties |
Acknowledgment and appraisal of exploration by other parties. |
Previous companies to have held the ground include Cluff Mining and Ashanti Goldfields. Exploration activities included RC and Diamond drilling. |
| Geology | Deposit type, geological setting and style of mineralisation. |
The Edikan deposits occur near the western flank of the Ashanti Greenstone Belt along the Obuasi- Akropong gold corridor. The Central Ashanti property is underlain principally by Paleoproterozoic Birimian metasediments of the Kumasi-Afema basin, positioned between the Ashanti and Sefwi Greenstone Belts. The flysch type metasediments consist of dacitic volcaniclastics, greywackes plus argillaceous (phyllitic) sediments, intensely folded, faulted and metamorphosed to upper greenschist facies. Minor cherty and manganiferous exhalative sediments are locally present, and graphitic schists coincide with the principal shear (thrust) zones. Numerous small Basin-type or Cape Coast- typegranitoids have intruded the sediments |
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| Criteria | JORC Code explanation | Commentary | Commentary |
|---|---|---|---|
| along several regional structures. AAF Gold mineralisation has been identified in a single granitoid intrusive over a strike of 2km between Abnabna and Fobinso. Most of the gold mineralisation is contained within 5 zones which range from 30m to 140m in width and have a moderate to steep northerly plunge. Mineralisation is associated with minor quartz veining and sulphides, which are predominantly pyrite. Associated host sediment Au mineralisation occurs along the margins of the granite. Fetish Gold mineralisation has been identified within, or is associated with, the margins of a granitoid intrusive which has intruded into a sequence of metasediments. Mineralisation is typically 40- 170m wide and remains open at depth. Mineralisation is associated with minor quartz veining and sulphides which are predominantly pyrite. Bokitsi Mineralisation at Bokitsi is concentrated and confined mainly within steeply dipping units hosted within sediments and schists. The mineralisation style differs from the majority of the other Perseus deposits, which are predominantly hosted within granites.. Mineralisation is associated with minor quartz veining and sulphides which are predominantly pyrite. Chirawewa, Esuajah North & Esuajah South Gold mineralisation has been identified within, or is associated with, the margins of a granitoid intrusive which has intruded into a sequence of metasediments. Mineralisation is typically 20- 120m wide and remains open at depth. Mineralisation is associated with minor quartz veining and sulphides which are predominantly pyrite. |
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| Drill hole information |
A summary of all information material to the under- standing of the exploration results including a tabulation of thefollowing informationfor all |
| Drill hole locations are shown on the map within the body of the underlying Mineral Resource reports. Significant drill hole intersections have |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Material drill holes: easting and northing of the drill hole collar elevation or RL (Reduced Level – elevation above sea level in metres) of the drill hole collar dip and azimuth of the hole down hole length and interception depth hole length If the exclusion of this information is justified on the basis that the information is not Material and this exclusion does not detract from the understanding of the report, the Competent Person should clearly explain why this is the case. |
been previously reported to the ASX. In the opinion of PRU all material drill results have been adequately reported. |
|
| Data aggregation methods |
In reporting Exploration Results, weighting averaging techniques, maximum and/or minimum grade truncations (e.g. cutting of high grades) and cut-off grades are usually Material and should be stated. Where aggregate intercepts incorporate short lengths of high grade results and longer lengths of low grade results, the procedure used for such aggregation should be stated and some typical examples of such aggregations should be shown in detail. The assumptions used for any reporting of metal equivalent values should be clearly stated. |
Exploration drill results have been previously reported by PRU. No aggregation of intercepts was carried out. Drilling intervals are predominantly even 1m, or composites of 2m or 4m. Mineralised composites are re-split to 1m for re-assay. Metal equivalent values are not being reported. |
| Relationship between mineralisation widths and intercept lengths |
These relationships are particularly important in the reporting of Exploration Results. If the geometry of the mineralisation with respect to the drill hole angle is known, its nature should be reported. If it is not known and only the down hole lengths are reported, there should be a clear statement to this effect (e.g.’down hole length, true width not known’). |
Drill holes are angled to local grid which is approximately perpendicular to the orientation of the mineralised trend. |
| Diagrams | Appropriate maps and sections (with scales) and tabulations of intercepts should be included for any significant discovery being reported. These should include, but not be limited to a plan view of drill hole collar locations and appropriate sectional views. |
A plan showing drilling on the deposits is included in the underlying Mineral Resource reports. |
| Balanced Reporting |
Accuracy and quality of surveys used to locate drill holes (collar and down-hole surveys), trenches, mine workings and other locations used in Mineral Resource estimation. Where comprehensive reporting of all Exploration Results is not practicable, representative reporting of both low and high grades and/or widths should be practiced to avoid misleading reporting of Exploration Results. |
Drill holes have been accurately located by PRU surveyors using the local grid system. Exploration results have been previously reported to the ASX and are not being reported for this Ore Reserve update. |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Other substantive exploration data |
Other exploration data, if meaningful and material, should be reported including (but not limited to): geological observations; geophysical survey results; geochemical survey results; bulk samples - size and method of treatment; metallurgical test results; bulk density, groundwater, geotechnical and rock characteristics; potential deleterious or contaminating substances. |
Ongoing bulk density determinations have been conducted by PRU using mine grab samples and existing stored drill core. Ongoing grade control drilling is conducted where a deposit is being actively mined. |
| Further work | The nature and scale of planned further work (e.g. tests for lateral extensions or depth extensions or large- scale step-out drilling). Diagrams clearly highlighting the areas of possible extensions, including the main geological interpretations and future drilling areas, provided this information is not commercially sensitive. |
No further exploration drilling is planned at the AAF deposit. Ongoing grade control drilling is conducted to define the mineralised lodes as the deposit is being mined. Further work at the other deposits will be guided by the results of pit optimisation analysis. Along strike and down dip lode extensions have been highlighted in the body of the underlying Mineral Resource reports. |
Section 3 Estimation and Reporting of Mineral Resources
| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Database integrity |
Measures taken to ensure that data has not been corrupted by, for example, transcription or keying errors, between its initial collection and its use for Mineral Resource estimation purposes. Data validation procedures used. |
The data base is systematically audited by PRU geologists. All drill logs are validated digitally by the database geologist once assay results are returned from the laboratory. In 2010, RUL reviewed the logging of several holes and validated the records in the database against the drill core and logging boards. No significant errors were noted. RPM also performed data audits in Surpac. For AAF RPM validated the 2013 data against previous data from the 2011 estimate. The dip and depth intervals of down hole surveys for a number of drill holes differed from the 2011 database. PRU instructed RPM to use the 2011 data for those holes as the errors were attributed to converting of the PRU current database to Datashed format. RPM noted that recent supplied grade control information contained duplicate hole_id’s. These have been documented and were sent to PRU. All the affected hole numbers were excluded from the current resource update. For Esuajah North RPM validated the 2013 data against previous data from the 2012 estimate. For Esuajah South RPM validated the 2013 data against previous data from the 2010 estimate. One drill hole (AKRDD256) had an incorrect prospect name so had not been used in previous estimates. The dip and depth intervals of down hole surveys for a number of drill holes differed from the 2010 database. PRU |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| instructed RPM to use the 2010 data for those holes as the errors were attributed to converting of the PRU current database to Datashed format. |
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| Site visits | Comment on any site visits undertaken by the Competent Person and the outcome of those visits. If no site visits have been undertaken indicate why this is the case. |
Site visits have been conducted by David Price (RUL) in January 2007, Paul Payne (RUL) in January 2008, and Aaron Green (RPM) in October 2010. On each occasion, the deposit area, the core logging and sampling facility, and drilling and sampling operations were viewed. Aaron Green inspected the main laboratory used by PRU. Notes and photos were taken. Discussions were held with site personnel regarding drilling and sampling procedures. No major issues were encountered. |
| Geological interpretation |
Confidence in (or conversely, the uncertainty of) the geological interpretation of the mineral deposit. Nature of the data used and of any assumptions made. The effect, if any, of alternative interpretations on Mineral Resource estimation. The use of geology in guiding and controlling Mineral Resource estimation. The factors affecting continuity both of grade and geology. |
The confidence in the geological interpretations of the Edikan deposits is considered to be good and is based on good quality drilling. Infill drilling has confirmed geological and grade continuity at each of the deposits AAF The deposit consists of steeply dipping mineralised granite lodes. Infill drilling has supported and refined the model and the current interpretation is considered robust. Outcropping of mineralisation and host rocks within the open pit currently being mined confirm the geometry of the mineralisation. Fetish & Chirawewa The deposits consist of steeply dipping mineralised granite and sediment lodes which have been interpreted based on logging of samples taken at regular intervals from angled drill holes. Bokitsi The deposit consists of moderate to steeply dipping mineralised sediment lodes which have been interpreted based on logging of samples taken at regular intervals from angled drill holes. Esuajah North The deposit primarily consists of a steeply dipping mineralised granite lode. Surface outcropping of mineralisation confirms the geometry of the mineralisation. Geological logging of drilling has generally confirmed the geometry of the mineralisation. Esuajah South The deposit consists of a steeply dipping granite lode and mineralised sediment lodes. Infill drilling has supported and refined the model and the current interpretation is considered robust. |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Outcropping of mineralisation and host rocks within the previously mined open pit confirm the geometry of the mineralisation. The logging of ‘granite’ is consistent and closely matches the observed mineralisation. |
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| Dimensions | The extent and variability of the Mineral Resource expressed as length (along strike or otherwise), plan width, and depth below surface to the upper and lower limits of the Mineral Resource. |
The AAF resource area extends over a strike length of 2,000m (from 25,750mE – 27,750mE), has an outcropping (within the existing pit) average width of 100m (13,680mN – 13,780mN) and includes the 600m vertical interval from 1,150mRL to 550mRL. The Fetish Mineral Resource area extends over a strike length of 550m (from 4,990mN – 5,540mN), has a typical width of 140m. It includes the 595m vertical interval from 1,180mRL to 585mRL. The Bokitsi Mineral Resource area extends over a strike length of 1,760m from 3,790mN to 5,550mN. The vertical extent of the Mineral Resource is 280m from surface at 1,180mRL to 900mRL. The Chirawewa Mineral Resource area extends over a strike length of 1,120m (from 3,780mN – 4,900mN), has an outcropping (within the existing pit) average width of 55m (3,900mE – 3,955mE) and includes the 310m vertical interval from 1,190mRL to 880mRL. The Esuajah North resource area extends over a strike length of 500m (from 7,000mN to 7,500mN), and includes the 470m vertical interval from 1,170mRL to 700mRL. The overall plan width of the mineralised lodes is 275m and extends from 2,225mE to 2,500mE. The Esuajah South resource area extends over a strike length of 300m (from 6,070mN – 6,370mN), has an outcropping (within the existing pit) average width of 50m (1,950mE – 2,000mE) and includes the 605m vertical interval from 1,160mRL to 555mRL. |
| Estimation and modelling techniques |
The nature and appropriateness of the estimation technique(s) applied and key assumptions, including treatment of extreme grade values, domaining, interpolation parameters and maximum distance of extrapolation from data points. If a computer assisted estimation method was chosen include a description of computer software and parameters used. The availability of check estimates, previous estimates and/or mine production records and whether the Mineral Resource estimate takes appropriate account of such data. |
Using parameters derived from modelled variograms, Ordinary Kriging (OK) was used to estimate average block grades within all main domains. The Inverse Distance to the power 2 (ID2) interpolation was used to estimate the minor lodes at Chirawewa and the sediment domain at Esuajah South Surpac software was used for the estimations. AAF Top-cuts ranging between 10g/t to 30g/t were applied to selected domains and based on statistical analysis. A total of 86 samples were cut. The parent block dimensions used were 10m NS by 10m EW by 10m vertical with sub-cells of 2.5m by 2.5m by 2.5m. The parent block size was selected on the basis of beingapproximately |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| 50% of the average drill hole spacing in the deposit. Fetish A top-cut of 25g/t was appropriate for granite hosted domains and a top-cut of 10g/t was used for sediment hosted domains. A total of 23 samples were cut. The parent block dimensions used were 10m NS by 5m EW by 10m vertical with sub-cells of 2.5m by 1.25m by 2.5m. The parent block size was selected on the basis of being approximately 50% of the average drill hole spacing in the deposit. Historical production records were available for shallow oxide pits completed in the 1990’s. Bokitsi Top-cuts of between 10g/t and 50g/t were used for the sediment hosted domains. A total of 20 samples were cut. The parent block dimensions used were 10m NS by 5m EW by 10m vertical with sub-cells of 2.5m by 1.25m by 2.5m. The parent block size was selected on the basis of being approximately 50% of the average drill hole spacing in the deposit. Historical production records were available for shallow oxide pits completed in the 1990’s Chirawewa A top-cut of 10g/t was appropriate for all objects, apart from Object 4 where a 15g/t top- cut was used for oxide mineralisation and 20g/t Au top-cut was used for fresh mineralisation based on statistical analysis. A total of 31 samples were cut. The parent block dimensions used were 10m NS by 5m EW by 10m vertical with sub-cells of 2.5m by 1.25m by 2.5m. The parent block size was selected on the basis of being approximately 50% of the average drill hole spacing in the deposit. No historical production records were available. Esuajah North A high grade cut of 20g/t was applied to all lodes. A total of 30 samples were cut. The parent block dimensions used were 10m NS by 10m EW by 20m vertical with sub-cells of 2.5m by 2.5m by 5m. The parent block size was selected on the basis of being approximately 50% of the average drill hole spacing in the deposit. Previous mining has occurred at the deposit as part of the Edikan Heap Leach Project which commenced production in November 1994 although mining records are not available for the |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Esuajah North deposit. Esuajah South A high grade cut of 40g/t was applied to the granite lode, and 15g/t to 30g/t for selected sediment lodes based on statistical analysis. A total of 19 samples were cut. The parent block dimensions used were 10m NS by 10m EW by 10m vertical with sub-cells of 2.5m by 2.5m by 2.5m. The parent block size was selected on the basis of being approximately 50% of the average drill hole spacing in the deposit. Reconciliation with historic production records was conducted by RUL in 2010. The discrepancies noted between the model and reported production was attributed to the pit having not been accurately surveyed, and currently filled with water. The mined portion of the model was based on the survey of the pit. RPM has completed numerous Mineral Resource estimates for the deposits since 2009. Each successive update was based on the previous estimate. For AAF mine reconciliation figures show that reconciliation is +8% for the AAF deposit to date. No assumptions have been made regarding recovery of by-products. No estimation of deleterious elements was carried out. Only Au was interpolated into the block models. An orientated ‘ellipsoid’ search was used to select data and was based on parameters taken from the variography or the observed lode geometry at each deposit. Three passes were used for each domain. The following search parameters were used at each deposit AAF - The first pass used a range of 30m, with a minimum of 10 samples. For the second pass, the range was extended to 60m, with a minimum of 6 samples. For the final pass, the range was extended to 250m, with a minimum of 2 samples. A maximum of 40 samples was used for all 3 passes with a maximum of 6 |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| The assumptions made regarding recovery of by- products. Estimation of deleterious elements or other non- grade variables of economic significance (eg sulphur for acid mine drainage characterisation). In the case of block model interpolation, the block size in relation to the average sample spacing and the search employed. Any assumptions behind modelling of selective mining units. Any assumptions about correlation between variables. Description of how the geological interpretation |
samples per drill hole. Bokitsi - The first pass used a range of 50m, with a minimum of 10 samples. For the second pass, the range was extended to 100m, with a minimum of 6 samples. For the final pass, the range was extended to 200m, with a minimum of 1 sample. A maximum of 40 samples was used for all 3 passes. Fetish - . The first pass used a range of 40m, with a minimum of 10 samples. For the second pass, the range was extended to 80m, with a minimum of 6 samples. For the final pass, the range was extended to 200m, with a minimum of 1 sample. A maximum of 40 samples was used for all 3 passes. Chirawewa - Three passes were used for each domain. The first pass used a range of 50m, with a minimum of 10 samples. For the second pass, the range was extended to 100m, with a minimum of 6 samples. For the final pass, the range was extended to 200m, with a minimum of 2 samples. A maximum of 40 samples was used for all 3 passes. Esuajah South - The first pass used a range of 30m, with a minimum of 6 to 10 samples. For the second pass, the range was extended to 60m, with a minimum of 4 to 6 samples. For the final pass, the range was extended to 180m to 240m, with a minimum of 2 to 4 samples. A maximum of 40 samples was used for all 3 passes for the granite domain, and 30 samples for the sediment domain. Esuajah North - The first pass used a range of 40m, with a minimum of 10 samples. For the second pass, the range was extended to 100m, with a minimum of 10 samples. For the final pass, the range was extended to 240m, with a minimum of 6 samples. A maximum of 40 samples was used for all 3 passes. Selective mining units were not modelled in the Mineral Resource models. The block size used in each model was based on drill sample spacing and lode orientation. Only Au assay data was available, therefore correlation analysis was notpossible. |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| was used to control the resource estimates. Discussion of basis for using or not using grade cutting or capping. The process of validation, the checking process used, the comparison of model data to drill hole data, and use of reconciliation data if available. |
The deposit mineralisation was constrained by wireframes constructed using a 0.2g/t Au cut-off grade in association with logged lithology codes. The wireframes were applied as hard boundaries in the estimate. Statistical analysis was carried out on data from 28 lodes for AAF, 30 lodes for Fetish, all lodes for Bokitsi, 14 lodes for Chirawewa . The high coefficient of variation and the scattering of high grade values observed on the histogram for some of the lodes suggested that high grade cuts were required if linear grade interpolation was to be carried out. As a result high grade cuts ranging between 10g/t to 30g/t (10-50g/t for Bokitsi) were applied to selected domains, resulting in a total of 86 samples being cut for AAF, 23 for Fetish, 20 for Bokitsi, 31 for Chirawewa. A three step process was used to validate each model. A qualitative assessment was completed by slicing sections through the block model in positions coincident with drilling. A quantitative assessment of the estimate was completed by comparing the average Au grades of the composite file input against the Au block model output for all the resource objects. A trend analysis was completed by comparing the interpolated blocks to the sample composite data within the granite domain. This analysis was completed for: 20m eastings and 10m bench heights for AAF; 20m northings and 20 bench heights for Fetish, Esuajah North and Esuajah South; 20m northings for Bokitsi; 20m northings and 10m bench heights for Chirawewa. Validation plots showed good correlation between the composite grades and the block modelgrades. |
|
| Moisture | Whether the tonnages are estimated on a dry basis or with natural moisture, and the method of determination of the moisture content. |
Tonnages and grades were estimated on a dry in situ basis. No moisture values were reviewed. |
| Cut-off parameters |
The basis of the adopted cut-off grade(s) or quality parameters applied. |
The Mineral Resource has been reported at a 0.4g/t Au cut-off based on assumptions about economic cut-off grades for open pit mining. PRU are currently mining the AAF deposit using a 0.4g/t cut-off. |
| Mining factors or assumptions |
Assumptions made regarding possible mining methods, minimum mining dimensions and internal (or, if applicable, external) mining dilution. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider potential mining methods, but the assumptions made regarding |
The AAF deposit is currently being mined using open pit techniques. The Fetish deposit is of similar style to that of the AAF deposit and could be mined using both open pit and underground methods. Theproximityof the Bokitsi deposit to AAF and |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| mining methods and parameters when estimating Mineral Resources may not always be rigorous. Where this is the case, this should be reported with an explanation of the basis of the mining assumptions made. |
the shallow, higher grade nature of the deposit suggests there is good potential for mining using both open pit and underground methods. The Chirawewa deposit is of similar style to that of the AAF deposit and could be mined using both open pit and underground methods. RPM has assumed that the Esuajah North deposit could potentially be mined using open pit techniques with some potential for large scale underground mining. RPM has assumed that the Esuajah South deposit could potentially be mined using large scale open pit and potentially underground techniques. Small scale open pit mining of the oxide material has previously occurred at Esuajah South. |
|
| Metallurgical factors or assumptions |
The basis for assumptions or predictions regarding metallurgical amenability. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider potential metallurgical methods, but the assumptions regarding metallurgical treatment processes and parameters made when reporting Mineral Resources may not always be rigorous. Where this is the case, this should be reported with an explanation of the basis of the metallurgical assumptions made. |
Extensive metallurgical test-work was completed on material from a number of deposits within Edikan Project area, by AMMTEC Pty Ltd in Perth for Cluff Plc in the early 1990’s. This focused on CIL test-work on both oxide and sulphide material and later to heap leach. Preliminary amalgamation and cyanidation results using bottle roll methodology confirmed the free milling nature of both the oxide and granite mineralisation. Metallurgical test-work was undertaken by PRU in 2011 as part of the DFS. Mineralisation characteristics of the granite hosted mineralisation at Fetish are similar to the mineralisation being processed at the AAF operation. Mineralisation characteristics of the sediment hosted mineralisation at Bokitsi are different to the mineralisation currently being processed at the Edikan operation. Metallurgical response is not as favourable as AAF but testwork has shown that gold recovery from Bokitsi is still adequate. |
| Environmental factors or assumptions |
Assumptions made regarding possible waste and process residue disposal options. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider the potential environmental impacts of the mining and processing operation. While at this stage the determination of potential environmental impacts, particularly for a greenfields project, may not always be well advanced, the status of early consideration of these potential environmental impacts should be reported. Where these aspects have not been considered this should be reported with an explanation of the environmental assumptions made. |
The Project is not subject to any environmental liabilities except for a progressive decommissioning and reclamation plan for the closed Ayanfuri heap leach mine. |
| Bulk density | Whether assumed or determined. If assumed, the basisfor the assumptions. If determined, the |
Bulk density values were originally determined at AAF from direct measurement of 738 |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| method used, whether wet or dry, the frequency of the measurements, the nature, size and representativeness of the samples. The bulk density for bulk material must have been measured by methods that adequately account for void spaces (vugs, porosity, etc), moisture and differences between rock and alteration zones within the deposit. Discuss assumptions for bulk density estimates used in the evaluation process of the different materials. |
diamond core samples of which 360 were conducted in-house by PRU and 378 completed by commercial laboratories. A recent study by PRU (2014) determined that the current density assigned to fresh granite was likely too high. This assumption was based on a better understanding of the granite lodes from open pit mining activities which suggested the material should be less dense than originally expected. A program of submitting existing drill core for analysis was instigated in early 2014. A total of 254 grab samples from the AAF pit and 485 drill core samples were sent to commercial laboratories for analysis.. Results suggested the fresh granite material had a density in the order of 2.7t/m3 and that fresh sediment material had a density of 2.77t/m3. These values have been assigned to this material type in the current RPM block models. Measurements were determined by wax coating samples and immersing in water. RPM recommends an ongoing program of submitting grab samples to laboratories for analysis. Suitable core samples from any future diamond drilling programs should be selectively sent for analysis. |
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| Classification | The basis for the classification of the Mineral Resources into varying confidence categories. Whether appropriate account has been taken of all relevant factors (ie relative confidence in tonnage/grade estimations, reliability of input data, confidence in continuity of geology and metal values, quality, quantity and distribution of the data). |
Mineral Resources were classified in accordance with the Australasian Code for the Reporting of Exploration Results, Mineral Resources and Ore Reserves (JORC, 2012). Classification at each deposit was based primarily on data quality, continuity of mineralization, drill spacing, and confidence in the geological interpretation and subsequent block model estimation. AAF The Mineral Resource was classified as Measured, Indicated and Inferred Mineral Resource. The Measured portion of the resource was defined where the drill spacing was predominantly at 20m by 20m, and continuity of mineralisation was robust. The portion of the deposit where the drill spacing was generally greater than 20m by 20m but still demonstrates good lode and grade continuity was classified as Indicated Mineral Resource. The portions of the deposit classified as Inferred include sparsely tested areas of the main zones, small zones peripheral to the main structures which are defined by four or less intersections with no clear lateral continuity, and zones of increased complexity which require more detailed information. Fetish The Mineral Resource was classified as Measured, Indicated and Inferred Mineral Resource on the basis of data quality, sample |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Whether the result appropriately reflects the Competent Person’s view of the deposit. |
spacing, and lode continuity. The Measured portion of the Mineral Resource was defined where the drill spacing was predominantly at 20m by 20m, and continuity of mineralisation was robust. The Indicated portion of the Mineral Resource was defined where the drill spacing was predominantly at 40m by 20m, and continuity of mineralisation was evident. The portions of the deposit classified as Inferred Mineral Resource include sparsely tested depth extensions of the main zones, and small zones peripheral to the main structures which appear to have poor clear lateral continuity or are untested. Bokitsi The Mineral Resource was classified as Measured, Indicated and Inferred Mineral Resource on the basis of data quality, sample spacing, and lode continuity. The Measured portion of the Mineral Resource was defined where the drill spacing was predominantly at 20m by 20m, and continuity of mineralisation was robust. The Indicated portion of the Mineral Resource was defined where the drill spacing was predominantly at 40m by 20m, and continuity of mineralisation was evident. The portions of the deposit classified as Inferred Mineral Resource include sparsely tested depth extensions of the main zones, and small zones peripheral to the main structures which appear to have poor clear lateral continuity or are untested. Chirawewa The Mineral Resource was classified as Indicated and Inferred Mineral Resource on the basis of data quality, sample spacing, and lode continuity. The Indicated portion of the Mineral Resource was defined where the drill spacing was predominantly at 20m by 20m, and continuity of mineralisation was good. The portions of the deposit classified as Inferred Mineral Resource include sparsely tested depth extensions of the main zones, and small zones peripheral to the main structures which appear to have poor clear lateral continuity or are untested. Esuajah North The Mineral Resource was classified as Measured, Indicated and Inferred Mineral Resource. The Measured portion of the resource was defined where the drill spacing was predominantlycloser than 20m by40m with |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| excellent continuity of the main mineralised zones within the granite. The Indicated portion of the resource was defined where the drill spacing was greater than 20m by 40m at the north and south margins of the granite where continuity of mineralisation was good. Areas of the resource defined at greater than 40m spacing, as well as the sediment to the south of the main granite, were classified as Inferred Mineral Resource. This includes the sparsely intersected depth extension of the mineralised granite. Esuajah South The Mineral Resource was classified as Measured, Indicated and Inferred Mineral Resource based on data quality, drill hole spacing, and continuity of mineralisation. The portion of the granite where the drill spacing was 20m by 20m or less and demonstrating good lode and grade continuity supported by high kriging efficiencies was classified as Measured Mineral Resource. This was confined to the central portion of the granite domain from surface down to 830mRL. The portion of the deposit where the drill spacing was generally greater than 20m by 20m but still demonstrated good lode and grade continuity was classified as Indicated Mineral Resource. The portion of the deposit classified as Inferred Mineral Resource included areas where the drill spacing was greater than 40m by 40m (generally the deeper portions of the granite), and the zones of mineralisation within the adjacent sediments that were defined by limited drilling. The input data is comprehensive in its coverage of the mineralisation and does not favour or misrepresent in-situ mineralization at each deposit. The definition of mineralised zones is based on high level geological understanding producing robust models of mineralised domains. The AAF model has been confirmed by infill drilling and mining which supported the interpretation. Validation of the block models shows good correlation of the input data to the estimated grades. The Mineral Resource estimates appropriately reflect the view of the Competent Persons. |
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| Audits or reviews |
The results of any audits or reviews of Mineral Resource estimates. |
Internal audits have been completed by RPM which verified the technical inputs, methodology, parameters and results of the estimate. |
| Discussion of relative accuracy/ confidence |
Where appropriate a statement of the relative accuracy and confidence level in the Mineral Resource estimate using an approach or procedure deemed appropriate by the Competent Person. For |
The Mineral Resource estimates have been reported with a high degree of confidence. The lode geometry and continuity has been robustly interpreted to reflect the Mineral Resource classification. The dataqualityisgood and the |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| example, the application of statistical or geostatistical procedures to quantify the relative accuracy of the resource within stated confidence limits, or, if such an approach is not deemed appropriate, a qualitative discussion of the factors that could affect the relative accuracy and confidence of the estimate. The statement should specify whether it relates to global or local estimates, and, if local, state the relevant tonnages, which should be relevant to technical and economic evaluation. Documentation should include assumptions made and the procedures used. These statements of relative accuracy and confidence of the estimate should be compared with production data, where available. |
drill holes have detailed logs produced by qualified geologists. Recognised laboratories have been used for all analyses. The Mineral Resource statement relates to global estimates of tonnes and grade. The AAF deposit is currently being mined using open pit techniques. Mine reconciliation to date shows 8% more tonnes mined when compared to the Mineral Resource model. The other deposits are not currently mined. Historical production records are available for the Fetish, Bokitsi and Esuajah South deposits. For Esuajah South previous mining of oxide material has been reconciled with the resource model reported in 2010. The model reported a reduced grade compared to production. The mined portion of the model was based on the survey of the mined pit, which has not been accurately surveyed, and is therefore only an estimate of what was mined. |
Section 4 Estimation and Reporting of Mineral Reserves
| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Mineral Resource estimate for conversion to Ore Reserves |
Description of the Mineral Resource estimate used as a basis for the conversion to an Ore Reserve. Clear statement as to whether the Mineral Resources are reported additional to, or inclusive of, the Ore Reserves. |
The Mineral Resources for Edikan were compiled by Graham de la Mare and reviewed by Paul Payne, a Competent Person who is a Member of the Australasian Institute of Mining and Metallurgy, and an Associate Consultant to RPM Mineral Resources quoted in this report are inclusive of Ore Reserves.Error! Reference source not found. |
| Site visits | Comment on any site visits undertaken by the Competent Person and the outcome of those visits. If no site visits have been undertaken indicate why this is the case. |
A site visit was undertaken at the Edikan Operation by Mr Joe McDiarmid on the 5th of August 2013. |
| Study status | The type and level of study undertaken to enable Mineral Resources to be converted to Ore Reserves. The Code requires that a study to at least Pre-Feasibility Study level has been undertaken to convert Mineral Resources to Ore Reserves. Such studies will |
The Mineral Resources have been converted to Ore Reserves by means of a Life of Mine plan including economic assessment. Key aspects of the study were technically achievable pit designs based on Pit Limit Optimisation. These designs were also assessed to ensure economic viability. |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| have been carried out and will have determined a mine plan that is technically achievable and economically viable, and that material Modifying Factors have been considered. |
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| Cut-off parameters | The basis of the cut-off grade(s) or quality parameters applied. |
The cut-off grade is based on the economic parameters developed for the Operation. The cut-off grade varies due to different material types as follows: Deposit Oxide Transition Fresh (g/t) (g/t) (g/t) AF Gap 0.35 0.50 0.45 Fobinso 0.60 0.50 0.40 Fetish 0.45 0.60 0.55 Bokitsi 0.45 0.60 0.50 Chirawew a 0.45 0.60 0.50 Esuajah North 0.45 0.60 0.50 Esuajah South 0.45 0.60 0.50 Error! Reference source not found. |
| Mining factors or assumptions |
The method and assumptions used as reported in the Pre- Feasibility or Feasibility Study to convert the Mineral Resource to an Ore Reserve (i.e. either by application of appropriate factors by optimisation or by preliminary or detailed design). The choice, nature and appropriateness of the selected mining method(s) and other mining parameters including associated design issues such as pre-strip, access, etc. The assumptions made regarding geotechnical parameters (eg pit slopes, stope sizes, etc), grade control and pre-production drilling. The major assumptions made and Mineral Resource model used for pit and stope optimisation (if appropriate). The mining dilution factors used. The mining recovery factors used. Any minimum mining widths used. The manner in which Inferred Mineral Resources are utilised in mining studies and the sensitivity of the outcome to |
The chosen method of mining is conventional open pit mining utilising hydraulic excavators and trucks, mining bench heights of 5 m with 2.5m flitches to minimise ore loss and waste rock dilution. The economic pit shell was defined using Whittle 4X pit optimisation software (“Whittle 4X”) with inputs such as geotechnical parameters, ore loss and dilution, metallurgical recovery and mining costs. The pit optimisation was run with revenue generated only by Measured and Indicated Mineral Resources. No value was allocated to Inferred Mineral Resources. Whittle 4X input parameters were generally based on Perseus’s operating site experience and supporting technical studies. The pit slope design assumptions are based on a geotechnical study by George, Orr and Associates. Overall pit slopes 30 to 50 degrees inclusive of berms spaced at between 5 and 20m vertically and berm widths of 5 to 12 m. Appropriate mining modifying factors such as ore loss, dilution and design parameters were used to convert the Mineral Resource to an Ore Reserve Mining dilution varies by deposit as result of block regularisation resulting in a range, due to multiple block models used, between 3- 12%. Minimum mining width of 40 m was generally applied to the pit designs. As the mine has been in operation and the mining method is not changed, only infrastructure needed to access new mining areas is required due to the selected mining method. RPM has not identified or been informed of any physical constraints to mining within the lease area. No property, infrastructure or environmental issues are known to exist which may limit the extent of mining within the mining lease. |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| their inclusion. The infrastructure requirements of the selected mining methods. |
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| Metallurgical factors or assumptions |
The metallurgical process proposed and the appropriateness of that process to the style of mineralisation. Whether the metallurgical process is well-tested technology or novel in nature. The nature, amount and representativeness of metallurgical test work undertaken, the nature of the metallurgical domaining applied and the corresponding metallurgical recovery factors applied. Any assumptions or allowances made for deleterious elements. The existence of any bulk sample or pilot scale test work and the degree to which such samples are considered representative of the orebody as a whole. For minerals that are defined by a specification, has the ore reserve estimation been based on the appropriate mineralogy to meet the specifications? |
The Edikan processing plant uses, crushing, grinding, gravity, flotation, concentrate regrind and cyanide leaching to extract gold. The plant has a nominal capacity of 7Mtpa. The technology used in the processing plant is well proven, and the plant has been operating successfully since 2011. The processing testwork is representative of the different material types throughout the Mining area No deleterious material has been identified The process metallurgical recovery for gold is fixed by material type in each deposit: AG oxide 61% transition 73.4% fresh 88% Fobinso oxide 61% transition 73.4% fresh 88% Fetish oxide 61% transition 73.4% fresh granite 91% fresh sediment 90% Bokitisi oxide 56.7% transition 69% fresh 82% Chirawewa oxide 59.5% transition 72% fresh 86% Esuajah North oxide 61% transition 73.4% fresh granite 93% fresh sediment 87% Esuajah South oxide 61% transition 73.4% fresh 94% |
| Environment | The status of studies of potential environmental impacts of the mining and processing operation. Details of waste rock characterisation and the consideration of potential sites, status of design options considered and, where applicable, the status of approvals for process residue storage and waste dumps should be reported. |
No environmental issues are known to exist which will prevent open pit mining and ore processing to continue to operate. Perseus appears to have sufficient space available for waste dumps to store the expected quantities of mine waste rock associated with the Edikan open pit Ore Reserve. Based on testing to date there is no risk of acid rock drainage as any potentially acid generating material is encapsulated within acid neutralising material. Edikan has sufficient capacity in its purpose designed and approved tailings storage facilities to meet the requirements generated from mining and processing quantities listed in for the Edikan Ore Reserve. The FTSF has been designed to contain up to 54 million tonnes of flotation tailings depending on the insitu density achieved in the deposited tailings. The final crest height of the embankments will be RL203m. The CTSF is double HDPE lined facility with underdrainage above the top liner and a leak detection system between the upper and lower liner. It has capacity for 1.5 Mm3 of tailings which is sufficient for the life of mine. |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Infrastructure | The existence of appropriate infrastructure: availability of land for plant development, power, water, transportation (particularly for bulk commodities), labour, accommodation; or the ease with which the infrastructure can beprovided, or accessed. |
Power supply is from grid system supplied by Ghanaian electricity company, GRIDCO Water supply is largely from groundwater extracted from dedicated boreholes and supplemented decant water for processing plant Access to site is via public road from Ayanfuri town A camp is established to accommodate non-local employees Workshops, offices, storage of reagents and laboratory is established at the processing plant |
| Costs | The derivation of, or assumptions made, regarding projected capital costs in the study. The methodology used to estimate operating costs. Allowances made for the content of deleterious elements. The derivation of assumptions made of metal or commodity price(s), for the principal minerals and co- products. The source of exchange rates used in the study. Derivation of transportation charges. The basis for forecasting or source of treatment and refining charges, penalties for failure to meet specification, etc. The allowances made for royalties payable, both Government andprivate. |
The mining cost as based on a schedule of rates provided by a Perseus mining contractor and historical data. All other operating costs have been provided by Perseus based on historical data. Non deleterious materials have been identified and costed Gold is the only metal considered in the Ore Reserves All cost are in US$ Bullion transportation and refining cost US$1.3/oz was applied A total royalty of 6.75% of the metal price was applied |
| Revenue factors | The derivation of, or assumptions made regarding revenue factors including head grade, metal or commodity price(s) exchange rates, transportation and treatment charges, penalties, net smelter returns, etc. The derivation of assumptions made of metal or commodity price(s), for the principal metals, minerals and co- products. |
A Gold price of US$1,200/oz was provided by Perseus and validated by RPM using published metal price forecasts. A Bullion and Refining cost of US$1.3oz was applied A total royalty of 6.75% of the metal price was applied |
| Market assessment | The demand, supply and stock situation for the particular commodity, consumption trends and factors likely to affect supply and demand into the future. A customer and competitor analysis along with the identification of likely market windowsfor theproduct. |
The demand for gold is considered in the gold price used. It was considered that gold will be marketable for beyond the processing life. The processing forecast and mine life are based on life of mine plans. The commodity is not an industrial metal |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Price and volume forecasts and the basis for these forecasts. For industrial minerals the customer specification, testing and acceptance requirements prior to a supply contract. |
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| Economic | The inputs to the economic analysis to produce the net present value (NPV) in the study, the source and confidence of these economic inputs including estimated inflation, discount rate, etc. NPV ranges and sensitivity to variations in the significant assumptions and inputs. |
A schedule and economic model has been completed using the Ore Reserves published in this Statement. The inputs used are as per those stated in the relevant sections of this Statement. The assessment used a discount rate of 10%, as supplied by Perseus, which is considered appropriate by RPM. The Base Case results in a positive economic outcome as assessed by a NPV calculation (@10% DCF). The NPV is most sensitive to the gold price. The NPV at a discount factor of 10%pa decreases by 50% with a US$100/oz decrease in gold price and increase by 30% with an US$100/oz increase in gold price. Error! Reference source not found. |
| Social | The status of agreements with key stakeholders and matters leading to social licence to operate. |
Perseus has established relevant agreements with local stakeholders. Perseus has and will continue to use skilled expatriate workers and locallysourced skilled workers. |
| Other | To the extent relevant, the impact of the following on the project and/or on the estimation and classification of the Ore Reserves: Any identified material naturally occurring risks. The status of material legal agreements and marketing arrangements. The status of governmental agreements and approvals critical to the viability of the project, such as mineral tenement status, and government and statutory approvals. There must be reasonable grounds to expect that all necessary Government approvals will be received within the timeframes anticipated in the Pre- Feasibility or Feasibility study. Highlight and discuss the materiality of any unresolved matter that is dependent on a third party on which extraction of the reserve is contingent. |
The estimate of Ore Reserves for the Edikan Open Pits are not, to RPM’s knowledge, materially affected by any known environmental, permitting, legal, title, taxation, socio-economic, marketing, political or other relevant factors that would prevent the classification of Ore Reserves. |
| Classification | The basis for the classification of the Ore Reserves into varying confidence categories. Whether the result |
Ore Reserves have been classified based on the underlying Mineral Resources classifications and the level of detail in the mine planning. The Mineral Resources were classified as Measured, Indicated and Inferred. The Ore Reserves, based only on the Measured and Indicated Resources, have been classified as Proven and Probable |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| appropriately reflects the Competent Person’s view of the deposit. The proportion of Probable Ore Reserves that have been derived from Measured Mineral Resources (if any). |
Ore Reserves, respectively. The Ore Reserve is classified as Proved and Probable in accordance with the JORC Code, corresponding to the Mineral Resource classifications of Measured and Indicated and taking into account other factors where relevant. The deposit’s geological model is well constrained. The Ore Reserve classification is considered appropriate given the nature of the deposit, the moderate grade variability, drilling density, structural complexity and mining history. Therefore it was deemed appropriate to use Measured Mineral Resources as a basis for Proven Reserves and Indicated Mineral Resources as a basis for Probable Reserves. No Inferred Mineral Resources were included in the Ore Reserve estimate. |
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| Audits or reviews | The results of any audits or reviews of Ore Reserve estimates. |
RPM has completed an internal review of the Ore Reserve estimate. The JORC Code provides guidelines which set out minimum standards, recommendations and guidelines for the Public Reporting of exploration results, Mineral Resources and Ore Reserves. Within the JORC Code is a “Checklist of Assessment and Reporting Criteria” (Table 1 – JORC Code). This checklist has been used as a systematic method to undertake a review of the underlying Study used to report in accordance with the JORC Code. A high level LOM Plan was prepared based on the ROM mineable ore contained with the pit designs. RPM reviewed the LOM Plan for reasonableness and accuracy and confirmed that it was suitable for estimation of Ore Reserves. An economic model was prepared by Perseus that confirmed the Operation to be economically viable. |
| Discussion of relative accuracy/ confidence |
Where appropriate a statement of the relative accuracy and confidence level in the Ore Reserve estimate using an approach or procedure deemed appropriate by the Competent Person. For example, the application of statistical or geostatistical procedures to quantify the relative accuracy of the reserve within stated confidence limits, or, if such an approach is not deemed appropriate, a qualitative discussion of the factors which could affect the relative accuracy and confidence of the estimate. The statement should specify whether it relates to global or local estimates, and, if local, state the relevant tonnages, which should be relevant to technical and economic evaluation. Documentation |
The accuracy and confidence of the inputs are, as a minimum, of a feasibility level (for the global open pit Ore Reserves). The key factors that are likely to affect the accuracy and confidence in the Ore Reserves are: oAccuracy of the underlying Resource Block Models; oChanges in gold prices and sales agreements; oChanges in metallurgical recovery; and oMining loss and dilution. The Ore Reserve has utilised all parameters provided by site as made available. The accuracy of the underlying Mineral Resources is defined by the Resource Category that the Mineral Resources are assigned to. Only the highest categories of Resource classification, Measured and Indicated, have been used as a basis for estimating Ore Reserves. |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| should include assumptions made and the procedures used. Accuracy and confidence discussions should extend to specific discussions of any applied Modifying Factors that may have a material impact on Ore Reserve viability, or for which there are remaining areas of uncertainty at the current study stage. It is recognised that this may not be possible or appropriate in all circumstances. These statements of relative accuracy and confidence of the estimate should be compared with production data, where available. |
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