Rainbow Rare Earths Limited announced positive results from the ongoing phased test work programme at the Phalaborwa Project, in South Africa. The test work is being conducted in conjunction with ANSTO Minerals in Australia and K-Technologies Inc. The results of the test work are enabling Rainbow to develop an economic rare earths extraction flowsheet currently as part of the feasibility study for the Project. Results to date have provided the Company with additional optimization opportunities to explore, which can reduce both operating and capital costs for the Project.

The next phase of the test work programme is now underway, which includes a number of trade-off and project optimization studies. Strong recoveries and optimization opportunities: The test work at ANSTO has confirmed that a simple acid leaching process is expected to allow 65-70% of the rare earths contained in the Phalaborwa gypsum stacks to be recovered in solution, with an average 66% leach recovery reported from preliminary metallurgical variability test work; The K-Tech purification and separation desktop study has confirmed the ability to deliver separated rare earths with over 99% purity oxides from the leach solution. Phalaborwa will be unique in producing separated Neodymium and Praseodymium (NdPr) oxide, Dysprosium (Dy) oxide and Terbium (Tb) oxide on site.

This will allow the full value of the rare earths to be realised - a 47% increase in revenue over the expected sales price for a mixed rare earth carbonate; Trade-off studies have started at both ANSTO and K-Tech to determine the optimal method to maximise the grade of rare earth elements in the leach solution prior to the final K-Tech separation step, whilst managing the build-up of impurities present in the gypsum stacks that could impact overall rare earth recovery. Increasing the leach solution grade by recycling the leach solution will significantly reduce both operating and capital costs.