Core Resources recently conducted metallurgical testing for Australian Strategic Materials (ASM) as part of their Rare Earth Options Assessment (REOA) for the Dubbo Project in New South Wales.

View the full ASX announcement here or read the summary below.

Conducted at Core’s metallurgical testing laboratory, the bottle roll program evaluated three composite samples from the Toongi ore body, HLC-West, HLC-Central, and HLC-East, under varying crush sizes and hydrochloric acid concentrations. The work used intermittent bottle roll testing (IBRT) to simulate heap leach conditions and forms a key part of the project’s evolving process engineering design.

Key outcomes from the HLC-West composite (representing the first 8–10 years of mine life):

• 12.5 mm crush size and 50 kg/t acid dose achieved:
  • Up to 85% recovery of praseodymium (Pr)
  • Up to 80% recovery of neodymium (Nd)
  • Up to 44% recovery of terbium (Tb)
  • Up to 38% recovery of dysprosium (Dy)
• Coarser particle sizes (12.5 mm – 25 mm) confirmed optimal leach performance, reducing crushing requirements

The bottle roll test results highlight that the Toongi deposit at the Dubbo Project shows strong potential for heap leaching for the recovery of rare earth oxides – including those restricted by Chinese export controls. These promising results suggest the potential to adopt a simplified, cost-effective process flowsheet by avoiding traditional high-cost steps like roasting and flotation. This would significantly reduce both capital and operational costs for the project.

Further column leach testwork is scheduled to commence June 2025.

Want to learn more about how Core Resources supports rare earth and critical mineral projects like Dubbo? Visit our metallurgical testing services page.