Positive Initial Metallurgical Test Results Point to Reduced CAPEX and OPEX Options for Marathon Gold's Valentine Lake Project
TORONTO, ON--(Marketwired - April 07, 2016) - Marathon Gold Corp. ("Marathon" or the "Company") (TSX: MOZ) announced today that it has received encouraging positive gold extraction results from bottle roll cyanide leach tests carried out on mineralized material from the Leprechaun and Marathon Deposits. This is first stage testing of material from the Valentine Lake project to assess the ores amenability to heap leaching technology. Thibault & Associates Inc. (an independent process chemical engineering firm) is engaged to carry out Marathon's 2016 metallurgical test work program. They report a gold extraction of 73.6% on minus 0.25" crushed core samples after 96 hours of bottle roll cyanide leach testing. Core from the Marathon and Leprechaun deposits had similar gold leachability characteristics and the data suggests that an increase in gold extraction may be possible with additional leaching time. The bottle roll tests indicated that the core samples from each deposit are amendable to heap leaching and short column tests are underway to assess gold leachability at a coarser crush size.
Highlights:
- The sample material was composited from half core samples that were within 150 meters of surface. These samples were within the pit shells of the Marathon and Leprechaun Deposits and were selected to represent as closely as possible the characteristics of the mineralization making up each resource. The core samples were un-oxidized. Oxidation is rarely present at Valentine Lake except in fractures near surface, so this material demonstrates very good leach potential for fresh rock.
- The Marathon and Leprechaun material was treated separately. The bottle roll and column samples were composited for a target grade of 1.5 g/t Au. The head grades for the metallurgical tests samples from the Marathon and Leprechaun deposits was determined to be, 1.73 g/t Au and 1.95 g/t Au respectively. Increases in grades from the core assays used to compose the metallurgical samples are consistent with the presence of coarse gold, which is common in each of the deposits found to date at the Valentine Gold Camp.
- The cyanide extraction of gold for the Marathon and Leprechaun bottle roll leaching tests was 73.6% after 96 hours with a 50% extraction of gold in the first 22 hours. The high leachability of gold on crushed ore justifies short column leach testing on ore at various crush sizes.
- The bottle roll tests were discontinued after 96 hours, even though gold was still being recovered, because there was sufficient data to proceed with more definitive column tests. The bottle roll test results by themselves indicate that heap leaching may be a viable process to use at the Valentine Lake project.
- Four short column tests are now underway to assess the leachability of gold using Leprechaun and Marathon cores samples at a larger crush size. Two 8" diameter columns will be used to assess a crush size of minus 0.75 inch and two 6" diameter columns will be used to assess a crush size of minus 0.5 inch. The column tests are expected to take a minimum of 90 days and will continue until the leach curves indicate liberation is effectively completed.
"The bottle roll tests are an excellent start to our metallurgical test program. Heap leaching with its lower capital and operating costs could be a dramatic change for the project. Heap leaching could also reduce the pit cutoff grade resulting in a lower waste to ore ratio and better pit economics. It could also give us options in processing such as run of mine heap leaching low grade ore and using a smaller mill to treat higher grade ore for optimized project economics," commented Phillip Walford, President of Marathon.
Marathon acknowledges the financial support of the GeoEXPLORE program of the Research and Development Corporation of Newfoundland and Labrador for this metallurgical study and the Junior Exploration Assistance program of the government of Newfoundland and Labrador for its ongoing exploration activities at the Valentine Gold Camp.
J. Dean Thibault, P.Eng., Senior Process Chemical Engineer of Thibault & Associates Inc. is the qualified person for this release and has reviewed the contents for accuracy and approved this release.
About Marathon Gold Corporation
Marathon is a Toronto based gold resource company focused on its 100% owned Valentine Gold Camp located in central Newfoundland. The Valentine Gold Camp currently hosts four near-surface, mainly pit-shell constrained, gold resources totaling 1,060,100 oz. gold at 2.20 g/t (Measured & Indicated) and 200,000 oz. gold at 2.85 g/t (Inferred), (April 2015). These resources, open along strike and to depth, cover less than 6% of the total length of the highly prospective Valentine Lake Thrust Fault and associated splay faults which host the majority of the gold mineralization within the property. For more information please visit www.marathon-gold.com.
CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION
Except for statements of historical fact relating to Marathon Gold Corp., certain information contained herein constitutes "forward-looking statements". Forward-looking statements include statements that are predictive in nature, depend upon or refer to future events or conditions, or include words such as "expects", "anticipates", "plans", "believes", "considers", "intends", "targets", or negative versions thereof and other similar expressions, or future or conditional verbs such as "may", "will", "should", "would" and "could". We provide forward-looking statements for the purpose of conveying information about our current expectations and plans relating to the future and readers are cautioned that such statements may not be appropriate for other purposes. By its nature, this information is subject to inherent risks and uncertainties that may be general or specific and which give rise to the possibility that expectations, forecasts, predictions, projections or conclusions will not prove to be accurate, that assumptions may not be correct and that objectives, strategic goals and priorities will not be achieved. These risks and uncertainties include but are not limited to those identified and reported in Marathon Gold Corp.'s public filings, which may be accessed at www.sedar.com. Other than as specifically required by law, we undertake no obligation to update any forward-looking statement to reflect events or circumstances after the date on which such statement is made, or to reflect the occurrence of unanticipated events, whether as a result of new information, future events, results or otherwise.
Contact
For more information, please contact:
Christopher Haldane
Investor Relations Manager
Tel: 1-416-987-0714
E-mail: chaldane@marathon-gold.com
Phillip Walford
President and Chief Executive Officer
Tel: 1-416-987-0711
E-mail: pwalford@marathon-gold.com