Ardea Resources Limited (ASX: ARL) has presented an updated JORC 2012-compliant Mineral Resource Estimate completed for the Goongarrie Nickel Cobalt Project (GNCP).
Using a 0.8% Ni cut-off grade, Ardea’s updated Measured Indicated & Inferred MRE is 60Mt at 1.0% Ni and 0.07% Co and Contained metal 595kt nickel and 44kt cobalt.
Goongarrie nickel cobalt project
The GNCP forms part of the broader Kalgoorlie Nickel Project (KNP), which Ardea owns 100% and is located within one of the world’s most infrastructure-rich and stable mining jurisdictions.
The GNCP encompasses four deposits of laterite mineralisation hosted in the regolith above ultramafic olivine cumulate rocks of the Walter Williams Formation. The project includes from north to south the Goongarrie Hill (GH), Goongarrie South (GS), Big Four (BF), and Scotia Dam (SD) deposits. These were the focus of a PFS completed by Ardea in 2018 that concluded the potential for a robust mining project with an IRR of 25% based on a 1.5Mtpa mining operation over 25 years.
Data for updated MRE for the GNCP
Following the completion of the 2018 PFS, Ardea completed substantial infill RC drilling at the GS, BF, and SD deposits targeting high grade regions of the deposits identified in the PFS to be the focus of mining operations for the initial 25 years of production upon the development of the project.
The infill RC drilling was augmented with significant diamond and sonic drilling to secure pilot plant materials for metallurgical test work and also enabled verification of the results from the historical and recent RC drilling and provide samples for systematic bulk density determinations of all the mineralised and waste material types identified within the GNCP.
Substantial infill RC drilling augmented with diamond and sonic drilling, R&D Xray Diffraction (XRD) mineralogy analyses and historical sample pulp re-analysis programmes by Ardea provided a wealth of new information.
The company has now used this information together with the large historical GNCP database to produce updated Mineral Resource Estimates for the entire GNCP, including the Goongarrie Hill (GH), Goongarrie South (GS), Big Four (BF), and Scotia Dam (SD) deposits.
High-grade updated MRE
Ardea said that the data from the Ardea 2018 RC and diamond drilling programmes, XRD mineralogy studies, and re-assaying of historical drill sample pulps has been used together with the vast historical exploration database for the GNCP to report the new Mineral Resources for the GNCP.
The Measured Indicated & Inferred MRE based on 0.8% Ni cut-off grade is 60Mt at 1.0% Ni and 0.07% Co and Contained metal 595kt nickel and 44kt cobalt; based on 0.5% Ni cut-off grade is 259Mt at 0.7% Ni and 0.05% Co and Contained metal 1,817kt nickel and 119kt cobalt; and based on 0.5% Ni cut-off grade is 826Mt at 0.7% Ni and 0.05% Co and Contained metal 5,817kt nickel and 384kt cobalt.
The GNCP nickel, cobalt, and scandium Mineral Resources based on a 0.8% Ni cut-off grade are as shown below.
The company reported the GNCP maiden scandium component 74Mt at 35ppm scandium. ARL said that GNCP is dominantly premium goethite mineralogy with excellent mineralised zonecontinuity, low acid consumption and good plant rheology. The company also noted manganese credit, indicating potential for Precursor Cathode Active Material (PCAM).
ARL also noted significant alumina credit within Clay Upper Goethite, recent Ardea R&Dindicates potential for High Purity Alumina (subject to bench-scale testing)
The company said that although no further drilling is currently planned to further evaluate the nickel laterite resources within the GNCP, it is anticipated that further sonic and diamond drilling may be required to collect more material for metallurgical test work as the project advances.
Ardea’s Managing Director, Andrew Penkethman, said: “The GNCP R&D product studies and resource update is the culmination of 12 months’ work and demonstrates that the GNCP is one of the largest and most strategic nickel-cobalt deposits in the developed world.
With the GNCP located 70km north of the City of Kalgoorlie-Boulder and the 25km long line of resources on granted mining leases, the project is strategically positioned to provide sustainable and ethical mineral supply in the premier mining jurisdiction in the world, Western Australia.
Most importantly for future project development, using a 0.8% nickel cut-off grade, the MRE is 60 million tonnes at 1% nickel with strong cobalt, scandium and aluminium credits. This is a significant project advancement.
The Company is targeting leach feed grades to a 2Mtpa High Pressure Acid Leach (HPAL) plant exceeding 1% nickel for 25 years. Ardea uniquely within Australian laterites has resource optionality due to the large size and exceptional quality of the KNP resources for mine high grading and selective recovery of key geo-metallurgical mineralisation types.
The GNCP also has significant manganese credits and thus has potential for Precursor Cathode Active Material (PCAM) for use in lithium-ion batteries (LIB). Of significance, the nickel-cobalt-manganese for use in NCM811 cathodes – 8 parts nickel, 1 part cobalt and 1 part manganese – approximates the KNP in-ground metal ratio.”
* Image source: Ardea Resources Limited