Sarama Resources Declares Maiden Inferred Mineral Resource of 1.5 Million Ounces Gold at the South Houndé Project
NEWS RELEASE
SEPTEMBER 16, 2013
SARAMA RESOURCES DECLARES MAIDEN INFERRED MINERAL RESOURCE OF 1.5 MILLION OUNCES GOLD AT THE SOUTH HOUNDÉ PROJECT
VANCOUVER, CANADA. Sarama Resources Ltd. (“Sarama” or the “Company”) is pleased to declare a maiden Inferred Mineral Resource1 estimate of 1.50 Moz of contained gold2 at its flagship South Houndé Project in south‐west Burkina Faso. The Mineral Resource represents a greenfields discovery, crystallising two years of exploration and demonstrating the potential of the Tankoro Structural Corridor to host mineralisation of significance.
Highlights
- 1.50 Moz gold contained in Inferred Mineral Resource – 29.13 Mt @ 1.6 g/t Au (at a 0.8 g/t Au cut‐off)
- Inferred Mineral Resource estimate includes 1.09 Moz @ 2.1 g/t Au3
- Oxide component of the Inferred Mineral Resource contains 267 koz of gold4
- Mineral Resources extend approximately 5.5km along strike in a trend that spans 1.1km across
- High‐grade zones in the MM Prospect extend to a vertical depth of 285m and represent promising exploration targets for underground mining
- Preliminary metallurgical testwork demonstrates viable processing routes for mineralisation with resulting extractions of 93% for oxide using a conventional cyanidation process and 90% for fresh rock using an oxidation stage prior to cyanidation
- Exploration activities to continue, with immediate focus on high‐grade extensional targets at the MC Prospect
1. Defined under Canadian National Instrument 43‐101 (“NI 43‐101”), Standards of Disclosure for Mineral Projects
2. Reported above 0.8 g/t Au for all material types
3. 16.36 Mt @ 2.1 g/t Au for 1.09 Moz reported above 1.2 g/t Au
4. 5.36 Mt @ 1.6 g/t Au for 267 koz reported above 0.8 g/t Au
Mineral Resource Estimate
The Mineral Resource estimate was undertaken by the independent and well‐established minerals industry consultancy, Cube Consulting Pty Ltd (Perth) and focused solely on exploration activities conducted at Sarama’s 100% owned Tankoro property, the key permit in the South Houndé Project.
The Inferred Mineral Resource of 29.13 Mt @ 1.6 g/t Au for 1.50 Moz (at 0.8 g/t Au cut‐off) is contained in a package of mineralised zones interpreted to extend over a strike length of approximately 5.5km, in a trend that spans 1.1km across the strike (refer Figure 1). The potential for further exploration success is supported by the size of the maiden Mineral Resource estimate and its location within the 30km‐long Tankoro Structural Corridor which was defined by soil geochemistry during first‐pass exploration. Drill testing of more recently identified geophysics targets has also shown the potential for blind deposits to be discovered on the large tenement position which now exceeds 1,000km2.
Sarama’s principal exploration activities have largely focused on the MM Prospect, which accounts for 74% of the gold in the Mineral Resource estimate, and includes several high‐grade shoots extending to a vertical depth of 285m below surface. These higher‐grade zones are reflected in the estimate, with 9.44 Mt @ 2.6 g/t Au for 789koz (at a 1.6 g/t Au cut‐off) representing 50% of contained gold within the Mineral Resource.
Exploration historically focused on open pit targets, however following drilling success on the MM Prospect, Sarama considers that the steeply‐dipping nature of the mineralisation and the presence of reasonably continuous high‐grade shoots indicate the potential to support underground mining in conjunction with open pit mining.
Tables 1 and 2 summarise the Inferred Mineral Resource and Appendix A contains detailed breakdowns as well as notes outlining the interpretation and estimation methodology.
Table 1 – Grade & Tonnage Statistics – Inferred Mineral Resource ‐ All Prospects & All Weathering Types
| Reporting Cut‐off Grade | Tonnage Above Cut‐off Grade | Average Grade Above Cut‐off Grade | Contained Gold Above Cut‐off Grade | Contained Metal Above Cut‐off Grade |
|---|---|---|---|---|
| g/t Au | Mt | g/t Au | koz Au | |
| 0 0.5 | 36.54 35.07 | 1.4 1.5 | 1,651 1,633 | 100% 99% |
| 0.8 | 29.13 | 1.6 | 1,504 | 91% |
| 1.0 1.2 1.6 2.0 2.5 3.0 | 22.88 16.36 9.44 5.43 2.91 2.08 | 1.8 2.1 2.6 3.2 4.1 4.6 | 1,324 1,094 789 558 379 307 | 80% 66% 48% 34% 23% 19% |
Table 2 – Inferred Mineral Resource by Weathering Type – Reported Above a 0.8 g/t Au Cut‐off Grade
| Weathering Type | Tonnage Above Cut‐off Grade | Average Grade Above Cut‐off Grade | Contained Gold Above Cut‐off Grade | Metal Contribution |
|---|---|---|---|---|
| Mt | g/t Au | koz Au | ||
| Oxide Transition Fresh | 5.36 1.28 22.49 | 1.6 1.6 1.6 | 267 64 1,172 | 18% 4% 78% |
| Total Inferred Mineral Resource | 29.13 | 1.6 | 1,504 | 100% |
Figure 1 – Mineral Resource Interpretations Overlying Soil Geochemistry Contours
Preliminary Metallurgical Testwork Program
A preliminary metallurgical testwork program was conducted by ALS Metallurgy Pty Ltd (Perth) under the supervision of Orway Mineral Consultants Pty Ltd (Perth) to determine indicative recoveries and understand the metallurgical behavior of the mineralisation within the area of the Mineral Resource. The testwork is regarded as preliminary and as such, parameters and flowsheets are un‐optimised. Notes outlining the testwork approach and detailed results are presented in Appendix B.
Individual oxide and fresh samples were tested for amenability to gold extraction by gravity and direct cyanidation methods, initially at a P80 grind size of 75 micron (“μm”).
Based on these results, gold mineralisation in the oxide material is highly amenable to direct cyanidation at a common P80 grind size of 75μm, realising an average gold extraction of 93.2% (total) when combined with a gravity stage. Very rapid leach kinetics were evident across all samples with near‐peak gold extraction levels being achieved after a leach residence time of only 2 hours. No preg‐robbing issues were apparent and cyanide and lime consumption was within acceptable levels.
The fresh mineralisation demonstrated low amenability to direct cyanidation at P80 grind sizes of 75μm and 45μm, but a good response to flotation and oxidation prior to cyanidation. Qualitative mineralogical analysis determined that the gold is present as fine particles (<10μm) of native gold/gold‐silver and several gold‐telluride species, all of which are strongly associated with the dominant pyrite mineralisation.
A series of flotation, ultra‐fine grinding and roasting tests were conducted to establish a viable processing route for the fresh mineralisation. In summary, the fresh mineralisation performed well using a process flowsheet featuring gravity, flotation, calcination and cyanidation stages with an overall gold extraction of 89.9% being achieved.
The results for the fresh mineralisation are very encouraging and clearly demonstrate the potential to achieve high gold recoveries when a high level of sulphide oxidation is attained. Flotation test work achieved a low feed‐to‐ concentrate mass pull of 6.1% at a coarse grind size of P80 150μm with approximately 94% of gold reporting to the flotation concentrate.
Overall gold extractions for the selected oxide and fresh processing flowsheets are summarized below in Table 3.
The results of the flotation testwork demonstrate the opportunity to incorporate an oxidative process stage within a future flowsheet to deliver high recoveries with only an incremental increase in operating costs over conventional cyanidation processing routes. The oxidative processes being tested use proven technology which is operating commercially in many gold processing facilities around the world.
Desktop amenability assessments for roasting and biological oxidation (BIOX®) processes indicate that the fresh mineralisation concentrate should be highly amenable to both technologies given observed key metrics such as gold:sulphur ratio, sulphide grade, sulphide:carbonate ratio and levels of deleterious elements.
Given that both of these oxidative processes are proven technologies and are used extensively in well‐established, modern and industrial‐scale gold operations by companies such as Barrick Gold, Newmont Mining, AngloGold Ashanti and Eldorado Gold, Sarama regards them as viable options and intends to conduct further testwork and assessment as the South Houndé Project progresses.
Table 3 ‐ Gold Extraction Summary – Selected Processing Flowsheets
| Contribution to Overall Gold Extraction | |||||||
| Test Series | Assayed | Gravity | Direct Leach | Flotation Con. Leach | Flotation Tail Leach | Overall Extraction | |
| Head | |||||||
| Grade | |||||||
| g/t Au | % | % | % | % | % | ||
| Oxide Material (Base Samples) Direct Cyanidation (75μm grind) Fresh Material (150 μm Float Con.) Roast + Calcine Regrind (45μm grind) | 2.67 3.55 | 0.6 0.4 | 92.6 ‐ | ‐ 85.5 | ‐ 4.0 | 93.2 89.9 |
The Company will prepare and file a technical report under National Instrument 43‐101 within 45 days of the date of this news release.
A conference call to discuss the content of this news release is scheduled for Tuesday, September 17, 2013 at 8:30am (Toronto time). To participate in the call, please dial +1 416 628 6611 and quote conference ID 60627424. Participants outside Canada can access local calling rates by using the numbers listed in Appendix C.
Sarama will be presenting at the Precious Metals Summit conference in Beaver Creek, September 18‐20, 2013 and will be present at the Denver Gold Forum in Denver, September 22‐23, 2013.
Sarama’s President and CEO, Andrew Dinning commented:
“We are very pleased to declare a maiden 1.5 Moz Au Inferred Mineral Resource for the South Houndé Project, which has been achieved in less than 2 years since Sarama’s initial public offering and reflects the efforts of our exploration team since the inception of the Company. The scale of the maiden Mineral Resource underscores the prospectivity of the South Houndé Project and further validates our exploration strategy.
We are also pleased to have identified viable metallurgical processing routes which feature commercially proven technology used in modern, gold processing facilities around the world and look forward to optimising the flowsheets to capitalise on the opportunities identified by the initial testwork.
The completion of this work represents an important milestone in our path to project development and will be used to guide our exploration efforts with a continuing bias towards grade and free‐milling material.”
For further information on the Company’s activities, please contact:
Andrew Dinning or Paul Schmiede
e: [email protected] t: +61 (0) 8 9363 7600
Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.
ABOUT SARAMA RESOURCES LTD
Sarama Resources Ltd (TSX‐V: SWA) is a West African focused gold explorer with substantial landholdings in Burkina Faso, Liberia and Mali.
Sarama’s flagship properties are situated within the Company’s South Houndé Project area in south‐west Burkina Faso. Located within the prolific Houndé greenstone belt, exploration programs have built on significant early success to deliver a maiden Inferred Mineral Resource estimate of 1.5 Moz gold. Outside of Burkina Faso, Sarama is focused on consolidating a number of under‐explored landholdings in other emerging and established mining jurisdictions.
Incorporated in 2010, the Company’s Board and management team have a proven track record in Africa and a strong history in the discovery and development of large‐scale gold deposits. Sarama is well positioned to build on its current success with a strong financial position and a sound exploration strategy across its property portfolio.
CAUTION REGARDING FORWARD LOOKING STATEMENTS
Information in this news release that is not a statement of historical fact constitutes forward‐looking information. Such forward‐looking information includes statements regarding the Company’s future exploration, the potential for open pit and underground mining at South Houndé and the maiden Mineral Resource estimate. Actual results, performance or achievements of the Company may vary from the results suggested by such forward‐looking statements due to known and unknown risks, uncertainties and other factors. Such factors include, among others, that the business of exploration for gold and other precious minerals involves a high degree of risk and is highly speculative in nature; Mineral Resources are not Mineral Reserves, they do not have demonstrated economic viability, and there is no certainty that they can be upgraded to Mineral Reserves through continued exploration; few properties that are explored are ultimately developed into producing mines; geological factors; the actual results of current and 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.
There can be no assurance that any mineralisation that is discovered will be proven to be economic, or that future required regulatory licensing or approvals will be obtained. However, 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 activities, the sufficiency of funding, the timely receipt of required approvals, the price of gold and other precious metals, that the Company will not be affected by adverse political events, the ability of the Company to operate in a safe, efficient and effective manner and the ability of the Company to obtain further financing as and when required and on reasonable terms. Readers should not place undue reliance on forward‐looking information.
Sarama does not undertake to update any forward‐looking information, except as required by applicable laws.
QUALIFIED PERSON’S STATEMENT
Scientific or technical information in this news release that relates to the Company’s exploration activities in Burkina Faso is based on information compiled or approved by Michel Mercier. Michel Mercier is an employee of Sarama Resources Ltd and is a member in good standing of the Ordre des Géologues du Québec and has sufficient experience which is relevant to the commodity, style of mineralisation under consideration and activity which he is undertaking to qualify as a Qualified Person under National Instrument 43‐101. Michel Mercier consents to the inclusion in this report of the information, in the form and context in which it appears.
Scientific or technical information in this news release that relates to the preparation of the Company’s Mineral Resource estimate is based on information compiled or approved by Adrian Shepherd. Adrian Shepherd is an employee of Cube Consulting Pty Ltd and is considered to be independent of Sarama Resources Ltd. Adrian Shepherd is a chartered professional member in good standing of the Australasian Institute of Mining and Metallurgy and has sufficient experience which is relevant to the commodity, style of mineralisation under consideration and activity which he is undertaking to qualify as a Qualified Person under National Instrument 43‐101. Adrian Shepherd consents to the inclusion in this report of the information, in the form and context in which it appears.
Scientific or technical information in this news release that relates to metallurgical testwork and mineral processing is based on information compiled or approved by John Fodor. John Fodor is an employee of Orway Mineral Consultants Pty Ltd and is considered to be independent of Sarama Resources Ltd. John Fodor is a Fellow in good standing of the Australasian Institute of Mining and Metallurgy and has sufficient experience which is relevant to the commodity, style of mineralisation under consideration and activity which he is undertaking to qualify as a Qualified Person under National Instrument 43‐101. John Fodor consents to the inclusion in this report of the information, in the form and context in which it appears.
APPENDIX A – MINERAL RESOURCE ESTIMATION
Notes
1. The Mineral Resource estimate was undertaken by Cube Consulting Pty Ltd (“Cube”), a minerals industry consultancy based in Perth, Western Australia, which is independent of Sarama.
2. The 5 prospect areas that are the subject of this Mineral Resource are located entirely on the Tankoro exploration property and the validated Mineral Resource drilling database for the estimated areas contained 58 diamond drillholes (12,945m), 343 reverse‐circulation (“RC”) drillholes (35,884m), an additional 68 RC drillholes with diamond drillhole tails (comprised of 7,582m RC and 6,581m diamond) and 200 air‐core (“AC”) drillholes (8,167m).
3. The Mineral Resource estimate used only diamond, RC and AC drilling data.
4. The diamond and RC drilling was completed in several phases by Sarama between 7/6/2011 and 24/5/2013.
5. Drilling was generally oriented on west‐east lines, with a range of drill‐line spacings varying from approximately 25m to 200m depending on geological complexity and the intent of the drill program.
6. Collars for drillholes used in the Mineral Resource estimate have been surveyed using a differential GPS system which is considered to provide a location accuracy of <10cm horizontally and <15cm vertically.
7. Downhole surveys have been conducted on all diamond and RC holes using either magnetic single‐shot or gyro multi‐shot electronic survey instruments.
8. Geological logging of drillholes includes state of weathering, lithology, alteration, mineralogy, structural defects and groundwater conditions. All drillhole logging data was compiled into a master drilling database.
9. RC drilling was logged and sampled over regular 1m intervals for the entire hole, whilst diamond holes were logged and sampled over varying intervals (average 0.85m sample length) according to geological observations. In the case of diamond drilling, samples submitted for assay were half‐core.
10. Diamond drilling completed at the MM, MC and collective Phantom prospects had average core recoveries of 97%, 96% and 98% respectively. The overall sample recovery for RC drilling was 90%. Localised zones of poor sample recovery caused by wet drilling conditions were assessed on an individual basis to determine the suitability for inclusion in the Mineral Resource estimation.
11. RC sample splitting was performed at Sarama’s preparation facilities in Burkina Faso. In the case of wet RC drilling, full samples were dried by wood‐fire prior to splitting. Diamond core sawing was also undertaken at Sarama’s preparation facility.
12. Sampling and sample submission was conducted in accordance with a quality assurance/quality control program which includes the use of certified reference materials for diamond, RC and AC drilling and field duplicates for RC drilling.
13. All drilling samples are securely bagged at the preparation facility and assigned sample identification numbers prior to their transport to assay laboratories in Burkina Faso and Mali operated by SGS S.A. and ALS Limited to international standards.
14. Gold content is determined by fire assay methods using a 50g charge, lead collection and an atomic absorption spectroscopy finish. Assay methods have a lower detection limit of 0.01 g/t Au.
15. Lithology, alteration, mineralisation, weathering and surface topography surfaces were interpreted in 3D by Cube using GEOVIA SurpacTM software.
16. Lithological, structural and alteration information from drillhole logging was primarily used to develop interpretations of the mineralised domains. Gold assays were used as a secondary determinant in the interpretations.
17. Mineralised interpretations generally honour a 0.25 g/t Au lower cut‐off. The interpretation was not typically extended more than 50m past the last drillhole intercept both along strike and down‐dip. However, sectional interpretations were extended further than 50m on some sections in some sparsely sampled areas where the geological and grade continuity could be reasonably assumed.
18. Additional criteria of a minimum 3m downhole interval length, and the minimisation of internal dilution were considered during the interpretation of the mineralised domains. However, internal dilution was incorporated where required to preserve the overall continuity of the mineralised domains.
19. The mineralisation interpretation consists of 85 individual domains, defined by lithological, weathering and spatial characteristics. Continuous mineralisation domains are visually robust and consistent across a range of cut‐offs from zero to 1.0 g/t Au.
20. The vertical extent of the interpreted Mineral Resource varies across the prospects with approximate vertical depths as follows: MM Prospect ‐ 285m, MC Prospect – 230m, Phantom Prospect – 130m, Phantom East Prospect
- 140m; and Phantom West Prospect – 120m.
21. For the purposes of density measurement, a total of 1,427 samples were collected from drilling across the prospects hosting the resource. Samples were collected from oxide, transitional and fresh material, as well as from all the representative lithologies. A density value was then assigned for each of the three weathering types and representative lithologies in the Mineral Resource estimate.
22. Two metre downhole composites were extracted from the assay database based on the mineralised wireframes and form the basis for statistical analysis, variography and grade interpolation.
23. Gold assays were reviewed on an individual domain basis to determine appropriate top‐cuts for each domain to reduce the influence of grade outliers. The top‐cuts that were applied to selected domains were all above the 95th grade percentile. In general, the grade domains represent distinct geological and statistical populations and provide a robust basis for Mineral Resource estimation.
24. Variography was completed by Cube to analyse the spatial continuity of the grade within the major mineralised domains using ISATIS® software. The resultant variogram models were used to determine the appropriate estimation parameters for grade interpolation into the block model.
25. Ordinary‐kriging methodology using GEOVIA SurpacTM software was used to perform the grade estimation. All block estimates were based on grade interpolation into parent cells with dimensions of 5m x 20m x 10m (XYZ) for each individual mineralised domain. The block model was rotated to a bearing of 25°N to better approximate the strike of the major mineralised domains.
26. Mineralised domains that lacked adequate data support for grade interpolation (<15 composites) were assigned the arithmetic mean cut gold grade of the 2m composites within the domain. Assigned block grades accounted for 8% of the total mineralised volume and 5% of the total contained metal at a 0 g/t Au cut‐off.
27. Upon completion of the block model, swath plots were generated to compare the estimated gold grades to the composited raw gold grades for every 50m cross sections for the major mineralised domains. The block model was further validated by conducting an ‘inverse‐distance‐squared’ estimate for comparison.
28. The Mineral Resource was classified as an Inferred Mineral Resource according to the Canadian Institute of Mining, Metallurgy and Petroleum (“CIM”) Definition Standards as required for NI 43‐101 compliance. Factors considered when classifying the Mineral Resource included data density, geological and grade continuity, drill spacing and drill quality, application of an appropriate estimation methodology and consideration of local estimation bias.
29. The final block model included the estimated mineralised domains, together with all material outside of the mineralised domains which were assigned waste parameters. The block model was assigned appropriate attributes which included prospect, weathering, lithology, density, estimation domain code, depletion and resource classification.
30. Tonnage‐grade curves were generated for a range of reporting cut‐off grades, material types and by prospect locations.
Table A1 – Inferred Mineral Resource by Prospect – Reported Above a 0.8 g/t Au Cut‐off Grade
| Prospect | Tonnage Above Cut‐off Grade | Average Grade Above Cut‐off Grade | Contained Gold Above Cut‐off Grade | Metal Contribution |
|---|---|---|---|---|
| Mt | g/t Au | koz Au | ||
| MM MC1 Phantom Phantom East Phantom West | 20.59 5.59 2.08 0.45 0.43 | 1.7 1.5 1.2 1.9 1.4 | 1,112 264 82 28 19 | 74% 18% 5% 2% 1% |
| Total Inferred Mineral Resource | 29.13 | 1.6 | 1,504 | 100% |
1. Previously referred to as the MM East Prospect
Table A2 – Inferred Mineral Resource ‐ Grade & Tonnage Statistics – All Prospects & All Weathering Types
| Reporting Cut‐off Grade | Tonnage Above Cut‐off Grade | Average Grade Above Cut‐off Grade | Contained Gold Above Cut‐off Grade | Contained Metal Above Cut‐off Grade |
|---|---|---|---|---|
| g/t Au | Mt | g/t Au | koz Au | |
| 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 | 36.54 36.54 36.42 36.17 35.95 35.07 33.51 31.90 | 1.4 1.4 1.4 1.4 1.4 1.5 1.5 1.5 | 1,651 1,651 1,650 1,648 1,646 1,633 1,605 1,571 | 100% 100% 100% 100% 100% 99% 97% 95% |
| 0.8 | 29.13 | 1.6 | 1,504 | 91% |
| 0.9 1.0 1.2 1.4 1.6 1.8 2.0 2.5 3.0 3.5 4.0 4.5 5.0 6.0 7.0 8.0 9.0 10.0 | 25.69 22.88 16.36 12.20 9.44 7.18 5.43 2.91 2.08 1.54 1.15 0.77 0.57 0.30 0.18 0.10 0.06 0.03 | 1.7 1.8 2.1 2.4 2.6 2.9 3.2 4.1 4.6 5.1 5.5 6.2 6.6 7.8 8.6 9.6 10.3 11.1 | 1,410 1,324 1,094 921 789 665 558 379 307 251 205 153 122 74 50 30 19 11 | 85% 80% 66% 56% 48% 40% 34% 23% 19% 15% 12% 9% 7% 4% 3% 2% 1% 1% |
| Oxide Material | ||||||
|---|---|---|---|---|---|---|
| Reporting Cut‐off Grade | Tonnage | Average Grade | Contained Gold | |||
| Above | Above | Above | ||||
| Cut‐off Grade | Cut‐off Grade | Cut‐off Grade | ||||
| g/t Au | Mt | g/t Au | koz Au | |||
| 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 | 6.90 6.90 6.90 6.86 6.82 6.64 6.26 5.86 | 1.3 1.3 1.3 1.4 1.4 1.4 1.4 1.5 | 298 298 298 298 298 295 288 280 | |||
| 0.8 | 5.36 | 1.6 | 267 | |||
| 0.9 1.0 1.2 1.4 1.6 1.8 2.0 2.5 3.0 3.5 4.0 4.5 5.0 6.0 7.0 8.0 9.0 10.0 | 4.57 4.11 2.99 2.22 1.77 1.40 1.05 0.52 0.34 0.22 0.15 0.08 0.04 0.01 ‐ ‐ ‐ ‐ | 1.7 1.8 2.0 2.3 2.4 2.6 2.9 3.6 4.0 4.4 4.7 5.2 5.7 6.5 ‐ ‐ ‐ ‐ | 246 232 192 160 139 119 97 59 44 32 22 13 7 2 ‐ ‐ ‐ ‐ |
| Transition Material | Fresh Material | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Tonnage | Average Grade | Contained Gold | Tonnage | Average Grade | Contained Gold | ||||||
| Above | Above | Above | Above | Above | Above | ||||||
| Cut‐off Grade | Cut‐off Grade | Cut‐off Grade | Cut‐off Grade | Cut‐off Grade | Cut‐off Grade | ||||||
| Mt | g/t Au | koz Au | Mt | g/t Au | koz Au | ||||||
| 1.61 1.61 1.61 1.60 1.59 1.55 1.45 1.36 | 1.4 1.4 1.4 1.4 1.4 1.4 1.5 1.5 | 71 71 71 71 71 70 68 66 | 28.03 28.03 27.91 27.72 27.55 26.87 25.80 24.67 | 1.4 1.4 1.4 1.4 1.4 1.5 1.5 1.5 | 1,282 1,282 1,281 1,280 1,278 1,268 1,249 1,225 | ||||||
| 1.28 | 1.6 | 64 | 22.49 | 1.6 | 1,172 | ||||||
| 1.14 1.00 0.75 0.57 0.43 0.32 0.26 0.11 0.07 0.05 0.04 0.02 0.01 ‐ ‐ ‐ ‐ ‐ | 1.7 1.8 2.0 2.2 2.4 2.6 2.9 3.7 4.2 4.7 5.0 5.5 6.0 ‐ ‐ ‐ ‐ ‐ | 60 56 47 40 33 28 23 13 10 7 6 4 2 ‐ ‐ ‐ ‐ ‐ | 19.99 17.76 12.62 9.41 7.24 5.45 4.12 2.28 1.66 1.27 0.97 0.67 0.52 0.28 0.18 0.10 0.06 0.03 | 1.7 1.8 2.1 2.4 2.7 3.0 3.3 4.2 4.7 5.2 5.7 6.3 6.7 7.9 8.7 9.6 10.3 11.1 | 1,104 1,036 854 721 617 519 438 307 253 212 177 136 113 71 50 30 19 11 |
APPENDIX B – PRELIMINARY METALLURGICAL TESTWORK
Notes
1. The metallurgical testwork program was undertaken by ALS Metallurgy Pty Ltd (Perth) under the supervision of Orway Mineral Consultants Pty Ltd (“Orway”), a minerals industry consultancy based in Perth, Western Australia, which is independent of Sarama.
2. Sample selection ensured representivity in terms of gold grade, mineralisation style, weathering type and spatial distribution. In total, 21 individual samples, weighing a total of approximately 345kg, were collected from the MM and MC Prospects.
3. The samples from the MM Prospect were sub‐categorised into ‘base’ and ‘variability’ samples in order to examine the effect of the above‐mentioned factors on the overall metallurgical extraction.
4. Gravity recovery tests were conducted on all 21 individual samples, initially at a P80 grind size of 75μm and subsequently at a P80 grind size of 45μm. In all tests, the gravity concentrate was subjected to amalgamation and the amalgam tail was returned to the gravity tail.
5. Cyanidation tests were conducted on the gravity tail for all 21 individual samples initially at a P80 grind size of 75μm and subsequently at a P80 grind size of 45μm. Conditions for these leach tests were pre‐oxygenation for 12 hours, 40% slurry density by weight, sufficient hydrated lime (60% CaO) to adjust pH to approximately 12.0, NaCN solution strength of 0.10% weight by volume (maintained above 0.025%) and a leach residence time of 48 hours with oxygen injection. The P80 45μm grind size tests on the fresh material were conducted with 200g/t Pb(NO3)2 added.
6. Mineralogical analyses were conducted on the leach residue for 4 of the individual fresh cyanidation samples.
7. A series of scout and bulk flotation tests was undertaken on a composite sample of the fresh mineralisation to produce a feedstock for further process testwork. Scout flotation tested sensitivity to grind size and reagent addition.
8. Mineralogical analyses were conducted on the bulk flotation concentrate and tail.
9. The bulk flotation concentrate was used as a feedstock for ultra‐fine grinding (“UFG”) testwork as P80 grind sizes of 20μm and 10μm. UFG products were subjected to cyanidation. Conditions for these leach tests were pre‐ oxygenation for 12 hours, 20% slurry density by weight, sufficient hydrated lime (60% CaO) to adjust pH to approximately 10.5, NaCN solution strength of 0.25% weight by volume (maintained above 0.125%) and a leach residence time of 48 hours with oxygen injection.
10. The bulk flotation concentrate was also used as a feedstock for roasting testwork, using a grind size ‘as received’ from the flotation stage. The roasting process created 2 product streams for cyanidation.
The first cyanidation test was performed on roast calcine at a grind size ‘as received’. Conditions for the leach tests included pre‐oxygenation for 12 hours, 20% slurry density by weight, sufficient hydrated lime (60% CaO) to adjust pH to approximately 10.5, NaCN solution strength of 0.25% weight by volume (maintained above 0.125%) and a leach residence time of 48 hours with oxygen injection.
The second cyanidation test was performed on a P80 45μm re‐grind of the roast calcine. Conditions for this leach test included pre‐oxygenation for 12 hours, 20% slurry density by weight, sufficient hydrated lime (60% CaO) to adjust pH to approximately 10.5, NaCN solution strength of 0.10% weight by volume (maintained above 0.05%) and a leach residence time of 48 hours with oxygen injection.
11. Mineralogical analysis was conducted on the leach residue of the calcine product that was re‐ground to P80 45μm.