Name of the Project
Phalaborwa rare earths project.

Location
Limpopo, South Africa.

Project Owner/s
London-listed Rainbow Rare Earths announced the signing of a binding agreement with Bosveld Phosphates for the co-development of the Phalaborwa rare earths project in November 2020.

On completion of a prefeasibility study (PFS), 70% of the project will be held by Rainbow and 30% by Bosveld, with a mechanism included to allow for Rainbow’s joint venture ownership to vary from 60% to 85%, depending on the results of the PFS.

Project Description
Rainbow Rare Earths and Bosveld Phosphates intend to jointly develop and process rare-earth elements (REEs) from the gypsum contained in two stacks at the project site.

Technical work undertaken to date has confirmed an inferred mineral resource estimate at Phalaborwa of 38.3-million tonnes at 0.43% total rare-earth oxides (REOs) contained within gypsum tailings stacked in unconsolidated dumps, derived from historical phosphate hard-rock mining.

High-value neodymium and praseodymium oxide represent 29.1% of the total contained REOs, with economic dysprosium and terbium oxide credits enhancing the overall value of the rare earth basket contained in the stacks.

Rainbow has determined it is possible to achieve strong recoveries through an acid leaching process, which will allow for between 65% and 70% of rare earths contained in the Phalaborwa gypsum stacks to be recovered in solution.

The company plans to use hydraulic reclamation of gypsum stacks, eliminating the costs traditionally associated with the primary mining, crushing and grinding of ore.

The reprocessing of these gypsum stacks carries significant environmental benefits, as it will redeposit clean, benign gypsum, which then has the potential for further use in the building and fertiliser industries.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
Not stated.

Capital Expenditure
Not stated.

Planned Start/End Date
Not stated.

Latest Developments
Rainbow Rare Earths has completed a process flowsheet to efficiently extract rare-earth elements from the phosphogypsum stacks at its Phalaborwa project.

The extraction process was developed alongside US-based K-Technologies, following extensive test work by the Australian Nuclear Science and Technology Organisation and at K-Tech’s facility.

The company says the rare earths extraction from phosphogypsum is impressive because it has historically proven to be technically, environmentally and economically challenging.

The extraction method delivers an overall recovery rate of between 65% and 70% of the contained rare earths, which compares favourably with the overall recovery of separated rare-earth oxides using standard processes.

Following the leaching of the phosphogypsum with sulphuric acid, and the subsequent rapid concentration of the rare earths in the pregnant leach solution, the concentrated rare earths solution is upgraded in K-Tech's proprietary continuous

ion-exchange and continuous ion-chromatography process to deliver high-purity oxides of the target magnet rare earths, namely neodymium, praseodymium, dysprosium and terbium.

Rainbow and K-Tech plan on jointly patenting the process and applying it to more rare earth projects in future.

With this milestone achieved, Rainbow will now focus on completing the technical feasibility study on the Phalaborwa project.

Key Contracts, Suppliers and Consultants
ANSTO Minerals (flowsheet process optimisation); and ANSTO Minerals K-Tech (testwork programme).

Contact Details for Project Information
Flagstaff Strategic and Investor Communications on behalf of Rainbow Rare Earths, tel +44 207 129 1474 or email rainbowrareearths@flagstaffcomms.com.