Cassini Resources Return Positive Metallurgy
THE INSIDE STORY: Cassini Resources (ASX: CZI) has made positive progress to the completion of ongoing Further Scoping Study (FSS) activities at the company’s West Musgrave project (WMP), located in Western Australia.
As part of the study, Cassini Resources has undertaken a detailed metallurgical testwork program, which represents the first stage of the Earn-in/JV Agreement the company has with OZ Minerals (ASX: OZL).
The testwork program has achieved the successful production of separate, saleable nickel and copper concentrates from all mineralised domains of the WMP, including the weathered ore-domains.
Cassini has interpreted the results to demonstrate metal concentrates produced from the WMP can be expected to be highly marketable with low impurities and a high iron:manganese-oxide ratio.
Metallurgical Testwork during Cassini’s 2015 scoping study focused on the relatively high head grade ore domains, which would be processed through a 1.5 million tonnes per annum treatment plant.
The scope of the FSS testwork program has been designed to cover whole ore composites and variability samples representative of the ore domains and average head grades aligned with the increased project size development options.
The work comprised 200 flotation tests and covered 17 variability composites from different mineralised domains covering a range of nickel and copper grades.
Two locked cycle tests on master composites, each representing typical run of mine material, of the early and later years of a likely mine schedule, were also tested.
The first of these, Master Composite A, comprised 10 per cent Nebo primary massive and breccia mineralisation, 30 per cent Nebo weathered massive and breccia mineralisation and 60 per cent Babel weathered disseminated mineralisation.
This composite approximates one of the potential processing streams during the first 2 years of operation.
The second, Master Composite B, comprised 50 per cent Nebo primary massive and breccia mineralisation, 48 per cent Babel primary disseminated mineralisation and 2 per cent Babel disseminated transition zone.
This master composite approximated potential processing streams in the latter years of operation.
Based on the results of Master Composite B, Cassini could reasonably target a final nickel concentrate grade of 10 to 12 per cent with recoveries in the range of 60 to 70 per cent.
The company considers the program to have made progress in de-risking the metallurgical component of the project by testing weathered mineralised domains, which usually result in lower nickel recoveries.
The copper recovery achieved appears to be only marginally lower in the weathered zones compared to primary zones while lower nickel recoveries in the weathered domains were determined to be primarily due to the effect on altered sulphide minerals, pyrite and violarite being the most dominant ones at NeboBabel.
“At the commencement of the FSS, there were two key technical outcomes we targeted to ensure the viability of the project,” Cassini Resources managing director Richard Bevan said.
“They were the identification of a near-by groundwater source, and confirmation that the metallurgy results we had previously achieved could be reproduced at lower nickel and copper grades and throughout the weathered zones.
“To have achieved positive outcomes in both of these is a fantastic result by the team and a significant step forward for the project.
“This metallurgical program confirms that there are no fatal flaws in the mineralogy and that the processing flowsheet will be comparable to other nickel and copper sulphide projects globally.
“We have now done a significant amount of metallurgical work for a scoping level study and are confident that we will continue to improve these outcomes as we progress through the next study phases.”
Further work is planned on the optimisation of concentrate grades and recoveries.
Additional locked cycle tests on multiple master composites, representing run of mine material across different ore domains and nickel and copper grades at various stages through the mine plan are to be conducted.
Recently a trial magnetic separation test on Nebo massive sulphide mineralisation was conducted as an alternative processing method aimed at improving nickel concentrate grade.
Results were encouraging, producing a 11.7 per cent nickel concentrate with greater than 80 per cent recovery, providing a proof of concept Cassini deems now needs to be applied to the disseminated styles of mineralisation, which if successful, could potentially lead to lower capital and operating costs.
Cassini Resources Limited (ASX: CZI)
…The Short Story
HEAD OFFICE
10 Richardson Street
West Perth WA 6005
Phone: +61 8 6164 8900
Email: admin@cassiniresources.com.au
Web: www.cassiniresources.com.au
DIRECTORS
Mike Young, Richard Bevan, Dr Jon Hronsky, Phil Warren, Greg Miles