Metallurgical Test Work Indicates Favorable Recoveries And Identifies Areas for Optimization at Marimaca

VANCOUVER - Marimaca Copper Corp. reported on the metallurgical test work which has been completed for its flagship Marimaca Copper Project, as well as an outline of the current detailed metallurgical work, which is ongoing and is expected to be completed in the current quarter.

Highlights: The three phases of column and bottle roll test work already completed indicated fast leaching and favorable recoveries, especially in the dominant oxide mineral zones which comprise the majority of the deposit - Average 84% recovery of the total copper was obtained in bottle roll testing completed on ore samples taken from mineral zones comprising the expected early years of mine life - Average recoveries were 4.8% higher than average acid soluble copper across all samples - Indicates leaching recovery, in a heap leach operation, is likely to exceed the acid soluble copper percentage for the mineral sub-zones of Marimaca; Phase 4 test work is underway and expected to be completed later this month with results to be released during Q3 - Includes material from La Atomica and Atahualpa which were outside of the original mine plan - Tests will include acid leaching with seawater, with and without added chloride ions, conducted in bottle rolls;  30cm mini-columns; 1.5m columns; and in a ROM leach characterization for low grade material; & Phase 5 test work will commence in Q3 to further refine results from first four phases and address variability across the deposit.

Michael Haworth, Executive Chairman said, “Metallurgy is one of the key de-risking milestones to address in the development of any mining project. For Marimaca, we have already completed multiple phases of test work to assess the deposit’s metallurgical characteristics. The results have been very pleasing, especially with respect to the materials which approximately comprise the first five years of the potential mine life, which is the all important payback period. The results show recoveries of over 84% of total copper, on average, in laboratory scale testing. Perhaps most importantly, these results exceeded the expected acid solubility ratio of the ore samples tested. This means that some of the minor copper bearing minerals, which weren’t initially identified as acid soluble, are also amenable to acid leaching and gives us great optimism for the potential for higher recoveries in an eventual heap leaching operation.

“It is also clear that, with the amount of technical work and de-risking milestones achieved already, we are well ahead of a typical PEA stage of development. The Phase 4 metallurgical program, which is due to be completed later this month and released during the third quarter, will significantly advance our knowledge and provide additional data across many parts of the deposit. This will provide the Company with a robust geometallurgical model which, in turn, will allow a detailed life of mine analysis of metallurgical recoveries for future studies. Phase 5, which is expected to commence in the 3rd quarter of this year, will allow us to focus on optimizing a very exciting copper project, as we move into the next phases of study.”