Name of the Project
Phalaborwa Rare Earths Project.

Location
Limpopo, South Africa.

Project Owner/s
London-listed Rainbow Rare Earths, which holds an 85% interest in the project.

Rainbow signed an agreement with phosphate mining company Bosveld Phosphates in June 2023 to acquire the remaining 15% interest in the project. Upon completion of the definitive feasibility study (DFS), the unincorporated joint venture (JV) will be transferred into an incorporated JV company and, at Rainbow’s election, Bosveld will transfer the assets required for the project into that company.

Project Description
The project is a near-term rare earths development project, based on the recovery of rare-earth elements (REEs) from phosphogypsum stacks generated from historic phosphate hard-rock mining and phosphoric-acid production. The project has a Joint Ore Reserves Committee-compliant mineral resource estimate of 35-million tonnes at 0.44% total rare-earth oxides (TREO) contained in two unconsolidated phosphogypsum stacks.

The project is being developed as a chemical processing operation rather than a conventional mine. Rainbow says the resource is already at surface and in a chemically cracked form, which eliminates the need for hard-rock mining, crushing, milling, flotation and cracking. This is expected to give Phalaborwa a lower operating-cost profile than traditional rare earths mining projects.

An updated interim economic study, released in December 2024, proposed a 16-year project life, based on the processing of an average of 2.2-million tonnes of phosphogypsum a year. The overall recovery rate is estimated at about 65%. The project is expected to produce about 1 850 t/y of separated neodymium/praseodymium (NdPr) oxides, as well as about 80 t/y of dysprosium and terbium, and about 140 t/y of yttrium within a samarium, europium and gadolinium-plus (SEG+) mixed rare-earth carbonate.

Rainbow’s process flowsheet provides for mechanical reclamation of the gypsum, followed by hydrometallurgical processing to recover the rare earths and produce a high-grade mixed rare earth product (MREP) for solvent extraction (SX) separation. Rainbow has selected SX as the final separation route. The company expects to produce separated NdPr oxide and a SEG+ mixed rare-earth carbonate, which will include dysprosium, terbium, samarium, europium, gadolinium and yttrium.

The flowsheet has been simplified through optimisation work, including the reduction of the leach process from three stages to two, a reduction in residence time from 32 hours to eight hours, and lower leach-heating requirements. Rainbow has also incorporated a purification process combining continuous ion-exchange and precipitation steps, as well as cerium depletion, to produce a high-grade feed stream for separation.

Phalaborwa is also expected to have environmental benefits, as the project will reprocess legacy phosphogypsum and associated acid water. The clean gypsum by-product will be deposited on newly lined stacks designed to International Finance Corporation and Equator Principles standards, with the potential to be sold into agricultural and industrial markets over time.

Potential Job Creation
Not disclosed in the interim study.

Net Present Value/Internal Rate of Return
The December 2024 interim economic study estimated an after-tax net present value, at a 10% discount rate, of $610.9-million, an after-tax internal rate of return of 38% and a payback period of two years. Average earnings before interest, taxes, depreciation and amortisation are estimated at $180-million a year over the 16-year project life.

Capital Expenditure
Capital costs are estimated at $326.1-million.

Planned Start/End Date
Rainbow expects to publish the DFS in 2026. On completion of the DFS, final permitting is expected to run in parallel with the project-finance process, allowing for construction to start by the end of 2027. First production is targeted for 2028, subject to completion of the DFS, permitting and financing.

Latest Developments
Rainbow reported in its interim results, published on March 31, 2026, that Phalaborwa had been established as a proven producer of REE, with the large-scale pilot plant in Johannesburg running the optimised primary flowsheet and producing a high-grade MREP.

The pilot plant initially produced a 55% TREO high-purity mixed rare-earth hydroxide, with subsequent improvements delivering a 78% TREO product. Rainbow expects the pilot-plant data to underpin the DFS, including mass balance, equipment sizing, capital and operating costs, as well as third-party validation for project finance.

The company remains focused on delivering the DFS for Phalaborwa in 2026. Rainbow completed an equity subscription on March 31, 2026, raising about $14.6-million from strategic investors, providing funds to complete the Phalaborwa DFS, the prefeasibility study for the Uberaba project, in Brazil, and general working capital beyond the end of the second quarter of 2027.

On May 5, 2026, Rainbow announced that it was evaluating a potential US stock exchange listing. The company said its core priorities remained the delivery of the Phalaborwa DFS in 2026 and the start of a prefeasibility study at Uberaba. Rainbow also noted continued support from the US International Development Finance Corporation, which has a $50-million option to provide project equity financing for Phalaborwa through strategic shareholder TechMet.

Key Contracts, Suppliers and Consultants
ANSTO Minerals (SX modelling and mineral testwork); K-Tech Inc (REO separation technology and back-end pilot plant work); Mintek (pilot plant and front-end testwork in South Africa); METC Engineering (PEA and DFS engineering work); and NEXUS Intertrade (letter of intent for benign gypsum offtake).

Contact Details for Project Information
Rainbow Rare Earths investor relations, Cathy Malins, tel +44 7876 796 629 or email cathym@rainbowrareearths.com. 
Tavistock Communications, on behalf of Rainbow Rare Earths, tel +44 20 7920 3150 or email rainbowrareearths@tavistock.co.uk.