Meridian Reports Initial Metallurgical Testwork Results from Cabaçal
Meridian Mining UK S has announced promising preliminary metallurgical results from its Cabaçal copper-gold project. The tests yielded a high-grade 29% copper concentrate with excellent recoveries of 94% for copper and 87% for gold. These figures significantly surpass historical resource assumptions, indicating strong open-pit potential. The metallurgical program is ongoing, aiming to validate high recoveries from the project's extensive mineralization. Meridian's results suggest efficiency in production methods and an environmentally friendly approach, which may enhance investor interest.
- High-grade 29% copper concentrate produced.
- Excellent recoveries: 94% for copper and 87% for gold.
- Metallurgical recoveries exceed historical resource assumptions by up to 9% for copper and 22% for gold.
- Ongoing metallurgical program with more results pending.
- None.
High-grade
LONDON, UK / ACCESSWIRE / July 20, 2022 / Meridian Mining UK S (TSX:MNO), (Frankfurt/Tradegate:2MM)(OTCQB:MRRDF), ("Meridian" or the "Company") is pleased to announce preliminary metallurgical results of Cabaçal's copper-gold VMS mineralization by SGS Lakefield in Canada. Meridian has completed its initial round of crushing, grinding, gravity-separation and flotation testing with the results highlighting the simple flowsheet needed to mill Cabaçal's copper-gold mineralization. These preliminary results are from representative samples[1] drilled across the deposit ("Figure 1") and indicate significantly higher recoveries of copper and gold than those used in the historical resource calculation[2] but are in-line with those recorded from the Cabaçal Mine's four-year production history. The metallurgical program is ongoing and more results are pending.
Highlights Reported Today
- Meridian achieves high-grade
29% copper concentrate from Cabaçal met program; - Meridian reports preliminary high recoveries of
94% for copper and87% for gold at Cabaçal; - Significantly higher metallurgical recoveries achieved to those used in the 2009 historical resource;
- Excellent metallurgy combined with robust grades of shallow copper-gold mineralization highlights open-pit potential at Cabaçal
- Cabaçal's copper-gold mineralization is liberated via a coarse grind of ~200 microns;
- Eco-friendly and simple flotation of Chalcopyrite via a frother and collection by Xanthate;
- Cleaner concentrates from partial regrind with lime addition to remove the gangue and depress pyrite;
- Representative concentrate samples to be made available for smelter performance analysis; and
- A Bond Work Index of 11.2 indicates medium soft rock as does the Abrasion Index of 0.28.
Dr Adrian McArthur, CEO and President comments: "These initial metallurgical results from Cabaçal's layers of copper-gold VMS mineralization are very consistent with the mine's historic ore production records and confirm that Cabaçal's mineralization responds very well to simple processing methods yielding clean concentrates with high grades of copper and gold via strong recoveries. This initial test work has been on the bulk mineralization and is ongoing while the testwork on the high-grade gold veins will commence shortly where we expect to replicate again the mine's high recoveries. These preliminary results exceed the recovery assumptions by up to
Cabaçal's Metallurgy Yields Promising Outcomes for Simple and Effective Processing of its Copper-Gold VMS Mineralization to Concentrate and Potentially for Doré Bars
Meridian took representative mineralized rock samples from a selection of drill holes representing typical mineralized zones from across the Southern, Central and Eastern Copper Zones in the Cabaçal mine setting, and from the unmined trends the Cabaçal Northwest Extension. These were sent to SGS Lakefield in Canada for the crushing, grinding, flotation and gravity separation test work. The best test result to date was from a batch test using optimum conditions produced a copper concentrate that contained
SGS created a master composite grading
Twelve flotation tests to date, have been conducted on the master composite using a range of variables including grind size, residence time, chemical additions, and gravity recovery. In all cases, the time required to float the sulphide minerals was typical for sulphide ores with the copper floating first followed by the other minor sulphides present. Gravity recovery has consistently been ~
Xanthate and frother were used in all the rougher flotation tests yielding resulting of typically
The cleaner tests were run using both a regrind or none as well as using fresh water or lime addition. The regrind to 45µm was very effective in separating the gangue material from the copper sulphides and the lime addition to pH 10 was very effective in depressing the pyrite and pyrrhotite present into the cleaner tails.
The standard Bond Work Index ("BWI") test was conducted on the Cabaçal rock which produced an average bond work index of 11. A BWI of between 12-15 is considered to be medium-soft hardness so Cabaçal's mineralization is relatively soft meaning it requires much less electricity to crush and grind one tonne of mineralization. The Project will potentially further benefit from being adjacent to the neighbouring low-cost hydro-electric generation plants supplying a clean, stable energy grid.
About Cabaçal
In November 2020, Meridian signed a Purchase Agreement to acquire
Meridian has defined an open 2,000m trend of shallow copper-gold mineralization centred on the Cabaçal Mine. This mineralization trends northwest-southeast, sub-crops along its northeast limits and dips to the southwest at 26° and is up 90m thick; presenting excellent open-pit geometry and mineral endowment. Meridian is currently focused on infilling this 2,000m zone.
Cabaçal's base and precious metal-rich mineralization is hosted by volcanogenic type, massive, semi-massive, stringer, and disseminated sulphides within units of deformed metavolcanic-sedimentary rocks ("VMS"). A later stage sub-vertical gold overprint event has emplaced high-grade gold mineralization truncating the dipping VMS layers. It was explored and developed by BP Minerals/Rio-Tinto from 1983 to 1991 and then by the Vendors in the mid 2000's. This historical exploration database includes over 83,000 metres of drilling, extensive regional mapping, soil surveys, metallurgy from production reports and both surface and airborne geophysics. The majority of Cabaçal's prosects remain to be tested.
Cabaçal has excellent infrastructure with access by all-weather road, industrial electricity provided by the adjacent hydroelectric power station supplying this clean energy grid, and local communities provide a large population to draw employees from. Cabaçal consists of 1 mining license, 1 mining lease application and 4 exploration claims which total 28,324 hectares. A further three licences totalling 15,941 Ha are awaiting formal transfer from the ANM following the licence auction system.
About Meridian
Meridian Mining UK S is focused on the acquisition, exploration, and development activities in Brazil. The Company is currently focused on resource development of the Cabaçal VMS copper-gold project, exploration in the Jaurú & Araputanga Greenstone belts located in the state of Mato Grosso; exploring the Espigão polymetallic project and the Mirante da Serra manganese project in the State of Rondônia Brazil.
On behalf of the Board of Directors of Meridian Mining UK S
Dr. Adrian McArthur
CEO, President, and Director
Executive Chairman
Meridian Mining UK S
Email: info@meridianmining.net.br
Ph: +1 (778) 715-6410 (PST)
Note
This metallurgical testwork has been undertaken at SGS Canada Minerals Lakefield which conforms to the requirements of ISO/IEC 17025 and is accredited by the Standards Council of Canada. Samples of half core were delivered and stage-crushed to -10 mesh (1.7 mm), blended, and rotary split into test charges. Head samples will be split from each of the sub-samples for assay and mineralogy. A master composite was generated by combining portions of the individual samples. Each of the variability samples and the master composite have been analysed by Cu by XRF, Au by fire assay, S by Leco, multi-elements by ICP scan, and specific gravity by pycnometer. Mineralogical review is conducted by QEMSCAN.
Qualified Person
Dr Adrian McArthur, B.Sc. Hons, PhD. FAusIMM., CEO and President of Meridian as well as a Qualified Person as defined by National Instrument 43-101, has supervised the preparation of the technical information in this news release.
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FORWARD-LOOKING STATEMENTS
Some statements in this news release contain forward-looking information or forward-looking statements for the purposes of applicable securities laws. These statements address future events and conditions and so involve inherent risks and uncertainties, as disclosed under the heading "Risk Factors" in under the heading "Risk Factors" in Meridian's most recent Annual Information Form filed on www.sedar.com. While these factors and assumptions are considered reasonable by Meridian, in light of management's experience and perception of current conditions and expected developments, Meridian can give no assurance that such expectations will prove to be correct. Any forward-looking statement speaks only as of the date on which it is made and, except as may be required by applicable securities laws, Meridian disclaims any intent or obligation to update any forward-looking statement, whether as a result of new information, future events, or results or otherwise.
Figure 1 Collar locations of core used in metallurgical program.
Figure 2 Rougher Grade-Recovery curves from Variability testing on Cabaçal's copper and gold mineralization reported today.
Table 1: Cabaçal Mine's Historical 1990 production results.
[1] Meridian news releases: December 13, 2021, January 31, February 7, March 22 and April 26, 2022
[2] Meridian news release August 26, 2020
SOURCE: Meridian Mining UK S
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https://www.accesswire.com/709068/Meridian-Reports-Initial-Metallurgical-Testwork-Results-from-Cabaal
FAQ
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