Western Australian explorer Dreadnought Resources (ASX:DRE) has produced a concentrate at an 85.9% total rare earth oxide (TREO) recovery from its Mangaroon Project in the Gascoyne region of Western Australia.
The testwork produced a concentrate containing 31.22% TREO and a neodymium-praseodymium concentrate of 10.76%. The company says this is a 12-fold increase from the head grade of 2.36% TREO and 0.87% Nd2O3+Pr6O11.
The company reports the metallurgical testwork tested the performance of the Yin ironstones using the flowsheet proposed for use at the Yangibana Ironstones Project owned by Hastings Technology Metals (ASX:HAS). This flowsheet has seen extensive testing and development across similar ironstones by Hastings and provides a likely shortcut to Dreadnought’s own flowsheet.
Dreadnought reports ongoing testwork will look at further optimising the flowsheet. Additionally, there will be an increased intensity of testing of all Yin ironstones that are expected to become resources across a range of head grades.
The company also says a bulk concentrate is being prepared to send to ANSTO for further analysis, as well as leaching and cracking work to produce a mixed rare earth carbonatite.
Commenting on the testwork, Dreadnought Resources Managing Director Dean Tuck says: “As the level of metallurgical work becomes more detailed, the ability to produce a high-value concentrate is maintained. Our metallurgical studies will continue, as too will the level of engagement with parties interested in potential concentrates.”
“As the level of metallurgical work becomes more detailed, the ability to produce a high-value concentrate is maintained”
Dreadnought says a composite sample of outcropping ironstone from Yin was submitted for metallurgical testing using the Hastings flowsheet prior to the 2022 drilling campaign, and though this sample contained a lower head grade, it produced a ‘high-grade’ concentrate containing 15.31% Nd2O3+Pr6O11 with a neodymium-praseodymium-to-TREO ratio of 36.7% and a mass recovery of 92.8%.
The company reports the difference in performance and outcomes between this program and its latest testwork is likely due to natural variations in mineralogy within the ironstones. The 2021 rock chip samples had no reported apatite in mineralogical analysis, whereas the drill composite contained some apatite resulting in a lower concentrate grade, which is supported by an increase in phosphorus in the concentrate.
The drill core composite tested in this work incorporates samples from 2 drillholes that comprise the oxidised zone of the Yin Ironstone resource.
Dreadnought says metallurgical testwork will now be undertaken across all newly discovered ironstones, with results expected in August 2023.
This work will be undertaken in conjunction with ALS, IMO, Primero, ANSTO, and ANU as part of a research and development project that seeks to develop an optimised flowsheet for all ironstones within the Yin Ironstone Complex.
Dreadnought Resources is a Western Australian mineral explorer focused on its 4 core projects in Western Australia: the Tarraji-Yampi Nickel-Copper-Gold, Mangaroon Nickel-Copper-PGE Joint Venture (JV) and REE-Gold, Central Yilgarn Gold, Base Metals, Critical Minerals, and Iron Ore, and Bresnahan Heavy Rare Earth Element (HREE) and Gold projects.
The Mangaroon Project covers over 5,300km-square of the Mangaroon Zone in the Gascoyne region of Western Australia, and part of the project is targeting nickel-copper-PGE in a JV with First Quantum Minerals (ASX:FQM).
In December 2022, the company delivered an independent inferred resource of 14.36 million tonnes @1.13% TREO, covering only 3km of the 43km strike within the Yin Ironstone Complex.
Write to Harry Mulholland at Mining.com.au
Images: Dreadnought Resources Ltd