Rainbow Rare Earths has officially transitioned its flagship Uberaba project in Minas Gerais, Brazil, into the pre-feasibility study phase alongside fertilizer giant The Mosaic Company. The strategic joint initiative aims to process industrial phosphogypsum byproduct stacks into high-value critical magnet materials. Official corporate disclosures confirm that the comprehensive engineering assessment and resource evaluation are scheduled for completion during the second half of 2027.
Transforming Industrial Byproducts into Strategic Raw Materials
The newly initiated pre-feasibility study focuses on designing an advanced on-site processing facility engineered to treat approximately 2.7 million tonnes of phosphogypsum stack material annually over an initial 30-year operational lifecycle. By utilizing existing industrial byproduct stacks rather than conventional hard-rock open pits, the project significantly reduces upfront land disturbance while successfully reclaiming high-value raw materials from vast surface accumulation sites across the region.
Preliminary geological modeling demonstrates a consistent baseline head grade averaging roughly 5,100 parts per million total rare earth oxides contained within the targeted phosphogypsum stacks. Project engineers highlight that because feedstock is continuously generated by Mosaic’s active fertilizer production facility, the Uberaba processing hub possesses operational scope to extend its active production lifetime well beyond the initial three-decade economic projections.
Pilot Testing Programs and Proprietary Chemical Flowsheets
To thoroughly validate processing performance and metallurgical recovery rates, Mosaic is currently shipping approximately six tonnes of raw phosphogypsum bulk material to Rainbow’s specialized laboratory and pilot plant facility in South Africa. This extensive physical testing program will stress-test continuous processing circuits, optimize chemical reagent consumption, and refine process flowsheets tailored specifically to the unique mineral composition of the Brazilian deposit.
The extraction circuit relies directly on proprietary processing technology originally developed and proven for Rainbow’s Phalaborwa asset. This specialized chemical flowsheet bypasses complex conventional cracking stages, allowing direct output of separated high-purity neodymium-praseodymium oxide alongside a refined SEG+ mixed rare earth carbonate. Technical specifications require these commercial-grade end products to consistently meet an extraordinary 99.5 percent industrial purity threshold.
Independent Resource Audits and Maiden JORC Estimates
International geological consultancy SRK Consulting has been formally appointed to prepare the maiden JORC-compliant mineral resource estimate for the Uberaba asset. Establishing an internationally accredited resource classification represents a crucial regulatory milestone, providing the standardized verification required to secure project-level debt financing, attract institutional equity, and structure binding off-take agreements with major industrial end-users globally.
The transition to pre-feasibility work builds on compelling economic metrics established in an initial economic assessment published earlier this year. Technical filings indicated a post-tax net present value discounted at ten percent of US$916 million, alongside a post-tax internal rate of return of 45 percent, utilizing benchmark commodity spot prices compiled in March 2026 for magnet-grade rare earth oxides.
Financial Metrics Point to Rapid Capital Recovery
Under baseline operational modeling, the Uberaba processing plant is projected to generate an average annual EBITDA of approximately US$217 million over its initial 30-year operational life. Furthermore, economic evaluations highlight an exceptionally short capital payback period of just 1.7 years, emphasizing the inherent structural cost advantages of secondary processing over conventional mining assets that require energy-intensive blasting, crushing, and milling operations.
Chief executive George Bennett noted that advancing the Brazilian asset demonstrates the commercial scalability of applying Rainbow's proprietary extraction intellectual property across phosphogypsum deposits worldwide. By establishing direct operational partnerships with established global fertilizer producers, the enterprise aims to construct a diversified, low-cost portfolio of critical mineral recovery facilities without incurring traditional exploration overhead or geological risks.
Strengthening Western Supply Chain Resilience for Magnet Metals
The expansion in Brazil arrives amid intensifying efforts by Western industrial nations to build resilient, transparent supply chains for magnet-oriented critical minerals. Neodymium and praseodymium are vital raw materials required for manufacturing high-strength permanent magnets, which drive electric vehicle propulsion systems, offshore wind turbines, advanced robotics, defense technologies, and specialized high-efficiency industrial motors essential for the global economy.
Extracting high-purity critical elements from existing industrial residue offers a significantly lower environmental and carbon footprint compared to standard greenfield hard-rock extraction operations. Industry analysts emphasize that recycling legacy phosphogypsum waste stacks simultaneously remediates historical industrial byproduct stockpiles while delivering a reliable secondary supply of strategic critical raw materials necessary to support international clean energy transition objectives.
Project Engineering Timeline and Long-Term Outlook
Over the next two years, joint technical teams will prioritize executing comprehensive environmental permitting programs, refining facility engineering schematics, and finalizing infrastructure access logistics. Concurrent commercial initiatives will focus on establishing binding off-take agreements with international magnet manufacturers, clean technology firms, and automotive original equipment manufacturers seeking transparent, non-monopolized critical material supply channels outside traditional dominant regional markets.
Market observers view the strategic collaboration between Rainbow Rare Earths and The Mosaic Company as a potentially transformative development for South America’s emerging critical minerals processing sector. If the upcoming pre-feasibility study successfully confirms technical and financial parameters in late 2027, the Uberaba plant will serve as a commercial model for sustainable secondary mineral extraction projects globally.