True Gold Mining Inc.: Final Metallurgical Results Validate Heap-Leach Process at Karma Project
Rapid oxide gold recoveries range from 90.2% to 97.4%
VANCOUVER, BRITISH COLUMBIA--(Marketwired - Sep 17, 2013) -
Editors Note: There are figures accompanying this press release.
True Gold Mining Inc. (TSX VENTURE:TGM) ("True Gold" or the "Company") is pleased to announce that results from metallurgical testing of oxide material from the three largest deposits at the Karma Gold Project ("Karma Project") in Burkina Faso provide unequivocal support for the project's proposed heap leach process1. Gold recoveries from oxide material at the Goulagou I, Goulagou II and Kao deposits were rapid and substantially complete within 10 days, with column leach recoveries ranging from 90.2% to 97.4%.
Importantly, tails assays from completed column leaching and bottle roll tests are strongly correlated indicating that, for the Karma Project oxide material, bottle rolls are strong predictors for actual column recoveries. Based on bottle roll tails, recoveries for Rambo and Nami oxide deposits are expected to be comparable to those described above. Collectively, oxide material in the five deposits represents approximately 80% of the total material in the proposed mine plan.
Phase One of the feasibility metallurgical testing program included nine columns for the Goulagou I, Goulagou II and Kao deposits and, to date, a total of 12 columns have been utilized on the oxide material to assess amenability to the heap leach process. The two phase metallurgical testing program is a key component of the Karma Feasibility Study and includes a total of 30 columns.
Phase Two, which is now underway, includes column leach tests of Nami and Rambo oxides, transition material (all deposits) and free-leaching sulphide material (Rambo and Nami). Completion of Phase Two is anticipated in October 2013.
The testing is being undertaken by McClelland Laboratories, Inc. (MLI), located in Sparks, Nevada. The metallurgical program was designed with input from SENET (Pty) Ltd.2, the lead Feasibility Study engineers, and Gary Simmons3, a technical advisor to True Gold.
Table 1: Summary of metallurgical results, column leach tests, Karma drill core composites
| g Au/mt | ||||
| Composite | Au Recovered %1 | Extracted | Calc'd. Head | Avg. Head2 |
| GGI Comp. 1 | 94.9 | 0.37 | 0.39 | 0.39 |
| GGI Comp. 2 | 93.9 | 0.61 | 0.65 | 0.67 |
| GGI Comp. 3 | 94.1 | 0.96 | 1.02 | 1.11 |
| GGII Comp. 1 | 91.1 | 0.31 | 0.34 | 0.33 |
| GGII Comp. 2 | 90.2 | 0.74 | 0.82 | 0.85 |
| GGII Comp. 3 | 91.5 | 1.40 | 1.53 | 1.42 |
| Kao Comp. 1 | 94.2 | 0.33 | 0.35 | 0.33 |
| Kao Comp. 2 | 97.4 | 0.75 | 0.77 | 0.78 |
| Kao Comp. 3 | 94.8 | 1.46 | 1.54 | 1.59 |
| 1) Column recoveries based upon the triplicate tail assays. 2) Average of all head grade determinations. |
To view Figure 1: Oxide gold leach rate profile for the Kao deposit, please visit the following link: http://www.marketwire.com/library/20130916-898663800.jpg
For oxide gold leach rate profiles of the Goulagou I and Goulagou II deposits, please click here: http://media3.marketwire.com/docs/898663.pdf
"Results from the metallurgical test work demonstrate that oxide material from Karma responds well to heap leaching and will contribute to low capital and operating costs," said Dwayne Melrose, President and CEO, True Gold. "The results received from the comprehensive metallurgical test program confirm the low variability that was proposed in the original project plan."
"The results reported today establish that the Karma Project's oxide material is consistent and predictable. I am particularly pleased with the correlation between calculated and assayed heads, as this adds a significant level of confidence to the results," added Steve Cole, P. Eng., Karma Project Manager and a metallurgist with 19 years of industry experience. "The test work undertaken on the project has significantly mitigated the metallurgical risk related to the known resource."
Discussion of results
Metallurgical test work results reveal that oxide-hosted gold at Goulagou I, Goulagou II and Kao is highly amenable to cyanidation, with cyanide consumptions ranging from 0.4 kg NaCN/mt to 1.1 kg NaCN/mt. Cyanide consumption on an operating basis is typically 25% of the results obtained from laboratory testing.
Cement is added as a binding agent during agglomeration in order to ensure percolation of leach solution is maximized through the heap. Non-optimised load permeability test work indicated that cement additions during agglomeration ranged from 10 kg/mt to 14 kg/mt (see Table 2). Test work also confirmed that cement addition was sufficient for pH control during leaching, therefore no lime was required. Cement addition optimisation test work is currently underway as part of the Feasibility Study.
Table 2: Summary reagent additions, column leach tests, Karma drill core composites
| Reagent Requirements, kg/mt | ||||
| Composite | Au Recovered % | NaCN Consumptions | Cement Addition | Lime Addition |
| GGI Comp. 1 | 94.9 | 0.60 | 10.0 | NA |
| GGI Comp. 2 | 93.9 | 1.06 | 10.0 | NA |
| GGI Comp. 3 | 94.1 | 0.49 | 10.0 | NA |
| GGII Comp. 1 | 91.1 | 0.61 | 10.0 | NA |
| GGII Comp. 2 | 90.2 | 0.75 | 11.0 | NA |
| GGII Comp. 3 | 91.5 | 0.60 | 11.0 | NA |
| Kao Comp. 1 | 94.2 | 0.50 | 10.0 | NA |
| Kao Comp. 2 | 97.4 | 0.45 | 14.0 | NA |
| Kao Comp. 3 | 94.8 | 0.37 | 14.0 | NA |
Program scope
Components within the scope of test work feeding into the overall metallurgical program results include the following:
- Metallurgical program based on over 1,000 samples to geochemically characterize ore
- Consideration of all forms of variability (material, weathering, location, depth, geochemistry) in preparation of composite samples for testing
- Analyses for CN solubility, preg-robbing, ICP, and carbon and sulfur content and speciation
- Comminution test work including determination of abrasion and Bond crushing indices
- X-ray diffraction mineralogy
- Pre and post-leach load permeability test work to optimize cement addition
- Bottle roll tests at 1.7 mm and 75 um to establish size-recovery relationships
| (1) The Company has not made a production decision and the Company's strategic plan to develop a stand-alone heap leach operation is subject to the results of its Feasibility Study, which is currently underway. Further, if and when the Company makes any production decision, it will disclose the basis of such decision in accordance with the requirements of National Instrument 43-101 Standards of Disclosure for Mineral Projects ("NI 43-101"). |
| (2) SENET (Pty) Ltd., one of the leading project management and engineering firms in the field of mineral processing, is conducting the Feasibility Study for the Karma Project. The Feasibility Study entails development of a comprehensive operating plan and cost estimate for an open-pit, heap-leach gold mine. |
| (3) Gary Simmons has more than 35 years of experience with mining companies in project management, process development, mill operations, design engineering, research and development and corporate due diligence. He played key roles with Fronteer Gold Inc. on the flagship Long Canyon and Northumberland projects, and was Senior Technical Director of Metallurgy and Technology for Newmont Mining Company. |
Stephen N. Cole, P. Eng., Karma Project Manager for True Gold, is the Company's designated "qualified person" for this news release within the meaning of NI 43-101 and has reviewed and verified that the technical information contained in this release is accurate and approves of the written disclosure of same. Mr. Cole was operations metallurgist for Gold Fields Ltd., project metallurgist for Gold Fields SA, process engineer for DRA, minerals processing manager for SGS-Lakefield and CEO of DRA Americas. He was also Engineering Manager for Aurora Energy Resources Inc. and Fronteer Gold Inc.
About True Gold
True Gold Mining Inc. is where gold comes to life. We are committed to growing a successful gold exploration, development and production company, by focusing on projects with low costs, low technical risks and solid economics. The Company's board, management and technical teams have proven track records in gold exploration, development, operations and production worldwide.
Additional information about the Company and its activities may be found on the Company's website at www.truegoldmining.com and under the Company's profile at www.sedar.com.
| ON BEHALF OF THE BOARD |
| "Dwayne Melrose" |
| Dwayne Melrose, President and CEO |
Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.
Certain statements made and information contained in this news release and elsewhere constitutes "forward-looking information" within the meaning of Canadian securities legislation. Such forward-looking statements are based on certain assumptions and are subject to risks and uncertainties which could cause actual events or results to differ from those reflected in the forward-looking statements, including, without limitation, with respect to statements regarding the potential to use heap leach method for gold processing, the continued low variability of the metallurgical response of oxide material from the Karma Project to heap leaching, the potential for lower capital and operating costs from the use of the heap leach method, the completion of additional metallurgical testing on schedule, the assumptions set forth in this news release and in the Company's news releases of August 20, 2013, October 3, 2012 and March 20, 2013, and risks and uncertainties relating to the interpretation of laboratory results and the estimation of potential gold recoveries, the geology, grade and continuity of mineral deposits, the possibility that future exploration and development results or the results of the Feasibility Study on the Karma Project will not be consistent with the Company's expectations, accidents, equipment breakdowns, risk of undiscovered, title defects and surface access, labour disputes, the potential for delays in exploration and permitting activities, the potential for unexpected costs and expenses, commodity price fluctuations, currency fluctuations, political risk and other risks and uncertainties, including those described under Risk Factors in each management discussion and analysis and in the Company's annual information form which are available under the Company's profile at www.sedar.com. Forward-looking information is based on various assumptions including, without limitation, the expectations and beliefs of management, the assumed long term price of gold, that the Company will receive required permits and access to surface rights, that the Company can access financing, appropriate equipment and sufficient labour and that the political environment within Burkina Faso will continue to support the development of environmentally safe mining projects. Should one or more of these risks and uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those described in forward-looking statements. Accordingly, readers are advised not to place undue reliance on forward-looking statements.
The Company does not undertake to update any forward-looking statement that may be made from time to time by the Company or on its behalf, except in accordance with applicable securities laws.
Contact
Vancouver Office:
604-801-5020
info@truegoldmining.com
Investor inquiries:
Alex Holmes, VP Business Development
604-697-4958
aholmes@truegoldmining.com
Media inquiries:
Ian Noble
604-809-8750
inoble@truegoldmining.com
