Australia’s next rare earths producer Hastings Technology Metals Limited (ASX: HAS) is pleased to announce that ore sorting test work on samples sourced across the Yangibana Rare Earths Project (Yangibana), in Western Australia’s Gascoyne region, has confirmed its suitability within the beneficiation process, delivering early gangue mineral rejection and a significant upgrade of rare earths material prior to the higher-cost processing steps.
Test work on adding an ore sorter to Yangibana’s process flowsheet has delivered the following significant life of mine improvements including:
- 26% upgrade to the life of mine total rare earths oxide (TREO) grade;
- 96% overall TREO recoveries after ore sorting;
- 7.1% improvement in concentrate recovery on sorted Simon’s Find ore samples;
- 8.0% improvement in concentrate recovery on sorted Bald Hill ore samples;
- 24% upfront mass rejection of primary crusher feed, resulting in:
- 24% reduction of beneficiation plant reagent consumption;
- 24% reduction in required tailings storage facility size for the life of mine; and
- effective mitigation of the risk of mining dilution.
- Ore sorting test work continues to validate the positive impacts on the Yangibana process flowsheet:
- Engineering development is progressing to incorporate the ore sorting circuit into the beneficiation process flowsheet.
The ore sorting test results confirmed that the total rare earths oxide (TREO) recovery through the ore sorter is a linear function, where the lower the head grade the higher the mass rejection becomes. It is therefore forecast, based on the average content of alumina and silica for all Yangibana deposits, that 24% of the proposed crusher feed will be rejected by the ore sorters as waste at the expense of only 4% TREO volumes across the life of mine (LOM) schedule.
The variability test work program was completed testing 12 samples from across the Yangibana deposits. The performance of the ore sorters is closely linked to head grade, resulting in LOM mass rejection of 24% with a corresponding increase in average grade of TREO content of 26%.
Commenting on the ore sorter test work, Hastings Technology Metals Chief Operating Officer Andrew Reid said:
“These results are enormously satisfying and exceeded all our expectations – the introduction of ore sorting has removed waste or very low-grade material to deliver a significant overall improvement in the mine head grade that will be put through the more advanced stages of Yangibana’s process flow sheet.
“This, in turn, has the potential to reduce Yangibana’s processing operating costs and further enhance the value of the industry high levels of neodymium and praseodymium (NdPr) contained in our ore bodies.
“Importantly, the rejection of the waste or very low-grade material at the front end of the process has had almost no impact on Yangibana’s LOM, underpinning the potential win-win of adding the ore sorter to the overall process flow sheet.
“Hastings will now progress the detailed design for an ore sorting system that can process 100% of Yangibana’s LOM mine feed material.”