The junior said the tech "achieves the separation of rare earth oxides in fewer stages with greater flexibility leading to significant capital and operating expenditure savings compared to traditional technology, which uses numerous solvent extraction steps to achieve the same results".

The deal, which covers the use of the technology across Southern Africa for an initial four-year period, will see Rainbow pay a licensing fee of US$5.5 million on each project where the tech is deployed.

George Bennett, CEO of Rainbow, said he thought the agreement "provides Rainbow with a significant competitive advantage and that the IP is ideally suited to our Phalaborwa Project, where it would enable us to focus on the separation of only the most valuable rare earth oxides within the basket - Nd/Pr, Dy and Tb".

The rare earth hopeful published a maiden mineral resource estimate for Phalaborwa and said it planned to complete a preliminary economic assessment in Q3.

The JORC compliant numbers showed an inferred MRE of 38.3 million tonnes, higher than the 35Mt expected from the project's gypsum stacks.

"If the results of a successful PEA currently underway at Phalaborwa are achieved using this proven separation technology, the IP will bring considerable benefits," said Bennett.

"In addition to the anticipated capex and opex savings, when compared to a traditional separation circuit, the IP will enable Rainbow to participate efficiently in the downstream separation process, allowing us to capture the full rare earth oxide price for our material," he added.