Amara Mining plc

Amara Mining plc

November 19, 2012 07:00 ET

Baomahun Resource Update

LONDON, UNITED KINGDOM--(Marketwire - Nov. 19, 2012) - Amara Mining plc ("Amara" or "the Company") (formerly Cluff Gold plc) (AIM:AMA) (TSX:AMZ), the dual AIM and TSX listed West African focused gold mining company, is pleased to announce a resource update for the Company's 100% owned Baomahun Gold Project ("Baomahun") in Sierra Leone.

  • Increased resource in the indicated category through addition of low grade halo around the existing high grade core: updated resource of 38.4Mt at 1.82g/t totalling 2.24Moz in the indicated category1 (previously 25.6Mt at 2.50g/t totalling 2.06Moz2)
  • High grade core of mineralisation maintained at 23.0Mt at 2.60g/t totalling 1.92Moz in the indicated category
  • Updated resource model significantly more robust following structural re-analysis
  • Additional exploration targets identified
  • On track for first gold production in 2015 with the Feasibility Study expected to be completed in H1 2013
  1. Using a 0.5g/t cut-off within a US$1,600/oz open pit shell and a 2.0g/t cut-off for resources suitable for underground mining
  2. Using a 1g/t cut-off within a US$1,500/oz open pit shell and a 1.5g/t cut-off for resources suitable for underground mining. See the technical report entitled "A 43-101 Technical Report, Mineral Resource Estimate at the Baomahun Gold Project" dated October 2011.

Peter Spivey, Chief Executive Officer of Amara, commented:

"The completion of the resource update for Baomahun, following the additional structural work, is a key step on our path to delivering long term value at the project. Not only does this represent a robust geological model for the development of our feasibility study, it also significantly increases our understanding of the genesis of the Baomahun deposit, highlighting a number of additional near term exploration targets and assisting with the long term exploration of our tenements. With the new geological model we move forward with increasing confidence as we complete the work required to develop Baomahun."

Management Conference Call
The management team of Amara will host a conference call for analysts and investors at 9:30am UK time today. Dial-in details are as follows:
Dial in number: +44 (0)20 33645381
Participant PIN Code: 8748028
A second conference call will be hosted at 9:30am EDT/2:30pm UK time today for North American analysts and investors. Dial-in details are as follows:
USA +1 212 444 0412
Other parts of the world +44 20 3450 9987
Participant PIN Code: 9425939

Structural Reinterpretation of the Baomahun Mineralisation

Following an internal review, Amara commenced a re-analysis of the structural controls on the gold mineralisation in the formation of Baomahun led by Dr Leslie Wright, an expert in structural geology with previous knowledge of the licence area. The work involved the re-logging of core samples in conjunction with additional structural mapping of the deposit. This work has confirmed the close relationship of gold mineralisation with various structural domains and mylonitised shear zones. This thorough understanding of the structural controls is vital not only for resource modelling, but also to understand the potential for additional resources defined in the project area.

The new geological model was prepared with an improved understanding of the geometry of the resource. Dr Wright's work pointed to two stages of contractional deformation which resulted in the sequential development of two major sets of folds. Gold mineralisation is interpreted to have initiated during the first phase of folding, and culminated during the second phase of folding, which defined the peak of deformation. Both sets of folds are defined by the geometry of key lithological markers in the subsurface.

A mineralised envelope was defined and modelled by Dr Jun Cowan, Principal Structural Geologist of Orefind Pty Ltd in Australia, and the conceptual founder of Leapfrog mining software. The envelope was defined at a 0.1g/t cut-off incorporating the structural observations of Dr Wright. The model also incorporated new structural insights made by Dr Cowan by modelling the data at the deposit scale using Leapfrog software, which independently was able to verify the fold geometries controlling the gold mineralisation. The aim was to use all of the mineralised material to inform the modelling process. These wireframes were then reconciled against the drill hole database.

Grade interpolation was completed using a local indicator kriging method. This work was completed in house with the assistance of AMC Consultants (UK) Ltd ("AMC"). This is a more sophisticated method of mapping the grades into the block model than the ordinary kriging methodology previously employed, which can have a tendency to smooth the grade distribution. It also deals with the high grades values present in the Baomahun deposit by limiting their sphere of influence relative to the lower grade material and allows for a better definition of high grade shoots. This new model will allow a more realistic resource schedule and optimised open pit to be prepared for the Baomahun feasibility study, work on which is now ongoing.

Additional Exploration Targets Identified

Drilling work has also recommenced at Baomahun, initially targeting five new zones within the resource area, which were highlighted by the re-analysis of the structural controls on the gold mineralisation. By definition, these targets mainly lie within areas of the pit shell that have been classified as waste and hence the discovery of additional mineralisation will have an enhanced impact on the overall project, in terms of grade and strip ratio.

Updated Resource Estimate

The updated resource is largely unchanged from the previous resource in terms of quantity of ounces. It confirms the presence of a robust high grade core to the deposit and recognises the presence of a more substantial lower grade halo than was previously estimated.

The resource estimate has been verified by SRK Consulting (UK) Limited ("SRK") in accordance with the Canadian Institute of Mining and Metallurgy and Petroleum ("CIM") Standards on Mineral Resources and Reserves as recognised by National Instrument 43-101 "Standards of Disclosure for Mineral Projects" of the Canadian Securities Administrators ("NI 43-101"). In order to satisfy the requirement for the mineral resource to show potential for economic extraction, the mineral resource estimate comprises mineralisation above a 0.5g/t cut-off and falling within an optimised pit shell derived using a US$1,600/oz gold price, plus mineralisation below this but above a 2g/t cut-off which SRK considers is potentially amenable to underground mining. Further details of the resource estimation parameters are set out in Appendix 1.

Tonnes (Mt ) Grade (g/t ) Gold (Moz )
Open Pit Indicated 34.9 1.62 1.82
Inferred 3.4 1.15 0.12
Underground Indicated 3.5 3.80 0.43
Inferred 3.2 3.95 0.41
Total Indicated 38.4 1.82 2.24
Inferred 6.6 2.52 0.54
  1. Using a 0.5g/t cut-off within a US$1,600/oz open pit shell and a 2.0g/t cut-off for resources suitable for underground mining

Whilst the overall grade of the mineral resource is lower than previously estimated (due to the lower cut-off grade: now 0.5g/t, previously 1g/t), the high grade core of the mineralisation has been retained. In addition, a significant number of additional tonnes of material previously regarded as waste have been interpolated as part of the updated resource wireframe model to produce a lower grade ore domain between and surrounding the previously defined high grade domains. This will have a beneficial impact on the eventual strip ratio.

For comparative purposes, a summary of the total resource estimate announced in September 2011 is compared to the updated mineral resource as at November 2012 in the table below. The September 2011 resource used a 1g/t cut-off for the open pit material and a 1.5g/t cut-off for the underground material and was optimised for potential open pit mining using a US$1,500/oz gold price. The updated mineral resources (combined open pit and underground) have been set out below using the same cut-off grades and optimisation parameters.

As at November 2012 As at September 2011
Tonnes (Mt ) Grade (g/t ) Gold (Moz ) Tonnes (Mt ) Grade (g/t ) Gold (Moz )
Indicated 23.0 2.60 1.92 25.6 2.50 2.06
Inferred 5.0 3.25 0.52 9.6 2.79 0.86
  1. Using a 1g/t cut-off within a US$1,500/oz open pit shell and a 1.5g/t cut-off for resources suitable for underground mining
  2. This should not be considered to be a mineral resource and has simply been derived in this manner to provide a like with like comparison to the 2011 estimate

This demonstrates that the high grade core of the mineralisation of Baomahun has been retained within the updated resource model, albeit with a slight fall in total contained metal primarily within the inferred category.

Strategy for Baomahun

Amara's strategy for Baomahun remains focused on delivering the feasibility study for the near term production opportunity whilst continuing to explore and demonstrate the long term resource potential for the area.

Amara's target to commence gold production at Baomahun in 2015 is intact. Delivering the feasibility study in H1 2013 will allow construction to commence at the start of the dry season in November 2013 and first gold to be poured in H2 2015. Work for the feasibility study is focused on the following:

  • Optimising the scheduling of the mine to allow the high grade core to be processed in the early years of production in the currently envisaged 2Mtpa plant to produce a robust payback
  • Reviewing the economic case for expanding the plant to 4Mtpa after the initial payback to allow production to remain at a high level while the lower grade material is processed
  • Crystallising the opportunity for hydro-electric power to provide a low cost production environment allowing for the lower grade material to be processed economically

The structural work also highlighted the significant potential that lies at depth below the current pit. High grade shoots are seen to improve with depth and structural work points to these structures coalescing. Our intention is to also investigate the depth potential of the deposit to evaluate the opportunity to maintain the production rate once lower grade material is being fed from the open pit by blending higher grade ore from underground sources. This is not expected to form part of the initial feasibility study.

Long term exploration potential

The new structural interpretation of the Baomahun deposit has also highlighted opportunities for long term resource growth through exploration. Drilling has recently recommenced following the cessation of the wet season in Sierra Leone, focused initially on targets within the existing resource area. The re-analysis highlighted five new targets with the potential to convert further areas of the currently envisaged open pit from waste to ore, maintaining the high grade core of the orebody. An initial 3,500m of drilling has been planned to test the five targets within the resource area, with a further 12,000m provisionally budgeted if any of these targets warrant further evaluation.

Amara will also continue to explore outside of the current resource area, with a mineral resource expected for the Pujehun South target in Q2 2013. Pujehun South is located approximately 800m north of the resource area and 36 holes have been drilled in 2012, outlining a 600m by 140m package of mineralisation. Initial results were announced on 29 February 2012 and drilling from March 2012 to date has returned significant individual intercepts, including:

  • 15m at 2.40g/t from 23m in hole EDH055
  • 14m at 2.14g/t from 45m in hole EDH078
  • 6m at 4.70g/t from 155m in hole EDH0107
  • 4m at 6.26g/t from 163m in hole EDH0108

However, as with the resource area, the mineralization consists of multiple intersections, for example in drill holes: EDH061, EDH086, EDH096 and EDH107. A full set of results from Pujehun South received after the last drilling update announced on 29 February 2012 is included in Appendix 2.

In addition, a number of new targets have been identified within the Makong South licence, located approximately 15km north of the existing resource area. Sampling of artisanal workings and new trenches has returned encouraging results, which has led to the implementation of a more aggressive trenching campaign. A further 4,500m of trenching is expected to be completed by mid Q1 2013 which will be followed up with a 1,000m drilling programme in Q2 2013 to enable Amara to obtain a better understanding of the controls on the mineralisation. The main target consists of a series of artisanal workings extending in a NNW-SSE direction for 1.9km.

Quality Assurance and Quality Control

Drill intersections from in-fill drill holes both in the Baomahun resource area and Pujehun South were calculated using a minimum width of 2m, a cut-off of 0.5g/t and up to 2m of internal waste. The intersections set out in Appendix 2 are from in-fill drill holes within the resource area and do not necessarily represent extensions to already defined zones of mineralisation. The true thickness of the mineralisation may vary from 40% to 100% of the intersected widths.

Drill cores for assaying were taken at a maximum of one metre intervals and were cut with a diamond saw. One half of the core was placed in sealed bags and sent to the Company's sample preparation facility at Baomahun, Sierra Leone. The core samples were then crushed to minus 4mm and split, with 1.0kg of sample pulverised down to 95% passing 106 microns. Approximately 120 grams of the pulverised sample were then shipped to a laboratory which is independent of the Company - the SGS Laboratory, Tarkwa, Ghana, where the samples were analysed for gold by fire assay using a 50g charge. As part of the Company's QA/QC procedures, internationally recognised standards, blanks and duplicate samples were inserted into the sample batches.

About Amara Mining plc

Amara (formerly Cluff Gold plc) is a gold developer-producer with assets in West Africa. The Company generates significant cash flow through its Kalsaka gold mine in Burkina Faso, where the production profile has been enhanced by the recent acquisition of the neighbouring Sega project. Amara remains focused on its objective of becoming a mid-tier producer through the development of its Baomahun project in Sierra Leone and its Yaoure project in Côte d'Ivoire. With its experience of bringing new mines into production and a project pipeline spanning Burkina Faso, Côte d'Ivoire and Mali, Amara aims to further increase its production profile with its highly prospective exploration work across all assets.

This report includes certain "forward-looking information" within the meaning of applicable Canadian securities legislation.

All statements other than statements of historical fact included in this report, including, without limitation, the positioning of the Company for future success, statements regarding exploration, production estimates and future objectives of Amara, are forward-looking information that involve various risks and uncertainties. There can be no assurance that such statements will prove to be accurate and actual results and future events could differ materially from those anticipated in such statements. Important factors that could cause actual results to differ materially from Amara's expectations include, among others, risks related to international operations, the actual results of current exploration and drilling activities, the results of the Baomahun feasibility study, changes in project parameters as plans continue to be refined as well as the future price of gold. Although Amara has attempted to identify important factors that could cause actual results to differ materially, there may be other factors that cause results not to be as anticipated, estimated or intended. There can be no assurance that such statements will prove to be accurate as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements. Amara does not undertake to update any forward-looking statements that are included herein, except in accordance with applicable securities laws.

Risk Factors:

Baomahun does not have identified Proven and Probable Mineral Reserves, which will be required as a basis for determining if Baomahun has bodies of commercial mineralisation. The costs, timing and complexities of upgrading the Mineral Resources at Baomahun to Proven and Probable Mineral Reserves could have a material adverse effect upon the Company and would materially and adversely affect our potential mineral production, profitability, financial performance and results of operations. Significant time and financial requirements are needed for bringing Baomahun into production and there can be no assurance that the Company will be able to accomplish this by 2015, or at all.

Mineral exploration and development involves a high degree of risk and few properties which are explored are ultimately developed into producing mines. With respect to Baomahun, substantial expenditures will be made by Amara to confirm Mineral Reserves which are sufficient to commercially mine such property, and to conclude appropriate fiscal stability agreements required to commence commercial operations. There can be no assurance that the Mineral Resources at Baomahun can be commercially mined or that the metallurgical processing will produce economically viable, saleable products. The decision as to whether a property contains a commercial mineral deposit and should be brought into production depends upon the results of exploration programs and/or feasibility studies, and the recommendations of duly qualified engineers and/or geologists, all of which involves significant expense. This decision will involve consideration and evaluation of several significant factors including, but not limited to: (1) costs of bringing Baomahun into production, including exploration and development work, preparation of feasibility studies and construction of production facilities; (2) availability and costs of financing; (3) ongoing costs of production; (4) market prices for the minerals to be produced; (5) environmental compliance regulations and restraints; and (6) political climate and/or governmental regulation and control. With respect to Baomahun we are currently preparing the feasibility study and economic analysis of the proposed operations. Until such is done, there can be no assurance that our proposed operations at Baomahun will be profitable and there can be no assurance that the feasibility study will be completed by H1 2013. Our ability to sell, and profit from the sale of any eventual mineral production from any of our properties will be subject to the prevailing conditions in the minerals marketplace at the time of sale. The global minerals marketplace is subject to global market conditions and changing attitudes of investors, consumers and other end-users' demand for gold. Many of these factors are beyond our control and therefore represent a market risk which could impact the long term viability of Amara and its operations.

Appendix 1: Resource Estimation Parameters
  1. The estimates of mineral resources were calculated in accordance with the definitions adopted by the Canadian Institute of Mining Metallurgy and Petroleum ("CIM") and incorporated into NI 43-101. The mineral resource estimate was carried out by Andrew Owusu Asante of Amara with assistance from David Boakye of AMC and Dr Andrew Richmond of Martlet Consultants Pty Ltd. Dr John Arthur and Dr Mike Armitage of SRK reviewed the on-going estimation procedure and final estimates and have approved the final Mineral Resource Statement derived from this work. Both Dr John Arthur (CGeol FGS, CEng MIMMM) and Dr Mike Armitage (CGeol FGS, CEng MIMMM) are Qualified Persons under the guidelines set out in NI 43-101 and have reviewed this press release for accuracy and compliance.
  2. The estimate of mineral resources may be materially affected by environmental, permitting, legal, marketing, or other relevant issues. For a full list of associated risk factors, please see the Risk Factors section of the footnotes.
  3. Ounces represent estimated gold content present in the tonnes of ore which would be mined and processed. Mining recovery, dilution and mill recovery rates have not been applied in calculating the contained ounces.
  4. In accordance with the guidelines set out by the CIM and contained within NI 43-101, this mineral resource estimate for the Baomahun property uses a 0.5 g/t Au cut-off within a pit shell optimised using a $1,600/oz Au to represent that portion of the resource which has "reasonable prospects for economic extraction" from an open pit mining scenario. In addition the block model below this pit shell has been interrogated using a 2.0g/t cut-off to represent those blocks with potential to satisfy an underground mining scenario.
  5. Amara's attributable portion of the mineral resource estimate is 100%.
  6. Tonnes and gold figures are rounded to the nearest '000. Grade is rounded to 2 decimal point. As a result, numbers may not add up due to rounding
  7. The geostatistical classification methodology used was based on a combination of kriging quality results in conjunction with the drill density and confidence in the resource wireframe model. The use of the kriging quality methodology provides a detailed audit of the kriging parameters used for grade interpolation and allows a sensitivity analysis to be performed to identify the optimum search parameters to be used for the final estimate. In the opinion of SRK this is a more appropriate methodology for the Baomahun deposit and generates a more robust classification.
Appendix 2 - Pujehun South drilling results
Interval lengths are not true widths. Composite intersections are based on a minimum width of 2m and a cut-off grade of 0.5 g/t.
Internal dilution of up to 2m has been allowed for continuity. No top cut. All holes, for which results have been received since 29 February 2012, have been included in the table.
Hole ID From
) To
) Interval
) Gold
) UTM East UTM North Elevation Azimuth Dip Zone
EDH055 23 38 15 2.4 205622 933825 426 255 45 Pujehun South
EDH058 24 27 3 3.49 205556 933684 330 255 45 Pujehun South
EDH059 91 99 8 0.63 205743 933501 288 255 45 Pujehun South
106 113 7 0.7
EDH061 0 3 3 0.68 205363 934100 255 255 45 Pujehun South
7 26 19 0.91
48 50 2 1.38
68 73 5 1.8
89 95 6 2.14
130 132 2 1.51
140 142 2 0.92
146 152 6 0.99
EDH062 12 14 2 3.63 205649 933485 250 255 45 Pujehun South
106 108 2 1.92
114 116 2 0.83
EDH063 0 205323 934240 358 236 50 Pujehun South
EDH077 0 205536 933446 217 255 45 Pujehun South
EDH078 45 59 14 2.14 205653 933845 440 255 45 Pujehun South
EDH079 0 205675 933800 425 255 45 Pujehun South
EDH080 26 30 4 0.74 205702 933753 407 255 45 Pujehun South
EDH081 5 10 5 2.27 205440 933911 337 255 45 Pujehun South
26 29 3 0.66
32 36 4 3.69
41 51 10 2.92
74 76 2 1.91
111 113 2 9.68
125 128 3 1.2
135 139 4 1.45
145 148 3 0.82
EDH082 91 94 3 2.95 205486 933932 340 255 48 Pujehun South
125 127 2 1.18
146 149 3 1.63
177 181 4 1.18
EDH083 0 5 5 0.9 205390 933890 326 255 48 Pujehun South
38 40 2 6.9
62 71 9 0.84
81 84 3 0.8
EDH084 101 104 3 0.9 205698 933865 447 255 48 Pujehun South
EDH085 44 47 3 1.1 205646 933838 440 255 48 Pujehun South
55 56 1 10.55
EDH086 47 54 7 1.8 205560 933917 398 255 48 Pujehun South
152 158 6 1.74
170 177 7 1.43
220 226 6 0.56
EDH087 121 125 4 0.51 205730 933817 432 255 48 Pujehun South
EDH089 133 137 4 0.54 205785 933797 420 255 48 Pujehun South
EDH090 205817 933767 375 255 48 Pujehun South
EDH092 205242 934096 239 255 45 Pujehun South
EDH093 205261 934058 224 255 45 Pujehun South
EDH095 39 44 5 1.06 205456 934025 276 225 48 Pujehun South
EDH096 24 30 6 1.54 205351 934144 278 255 50 Pujehun South
EDH097 205147 934168 263 255 48 Pujehun South
EDH098 205093 934249 259 255 48 Pujehun South
EDH099 205173 934295 294 255 50 Pujehun South
EDH100 172 5 0.755 205250 934220 331 255 50 Pujehun South
EDH101 135 141 6 3.18 205416 934188 336 255 52 Pujehun South
EDH102 206150 933572 230 255 50 Pujehun South
EDH103 206003 933626 304 255 46 Pujehun South
EDH104 205916 933667 310 255 255 Pujehun South
EDH105 205398 934276 353 253 45.2 Pujehun South
EDH106 205516 934080 270 254 45 Pujehun South
EDH107 49 52 3 1.45 205474 934146 309 252 50 Pujehun South
64 67 3 1.31
138 143 5 1.5
155 161 6 4.7
EDH108 28 30 2 1.66 205516 934039 289 255 50 Pujehun South
116 118 2 0.08
125 127 2 0.66
163 167 4 6.26
EDH109 105 107 2 2.88 205550 933968 375 255 50 Pujehun South
162 164 2 1.78
180 183 3 2.07
EDH110 147 151 4 3.58 205612 933930 400 263 48 Pujehun South

Contact Information

  • Amara Mining plc
    John McGloin, Chairman
    Peter Spivey, Chief Executive Officer
    Pete Gardner, Finance Director
    Katharine Sutton, Head of Investor Relations
    +44 (0)20 7398 1420

    Canaccord Genuity Limited
    (Nominated Adviser & Broker, London)
    Rob Collins
    Sebastian Jones
    Joe Weaving
    +44 (0)20 7523 8350

    Pelham Bell Pottinger
    (Financial Public Relations)
    Charlie Vivian
    Daniel Thöle
    James MacFarlane
    +44 (0)20 7861 3232