Mosaic and Rainbow Rare Earths Launch Pre‑Feasibility Study on Uberaba Rare Earths Project

The Mosaic Company (NYSE: MOS) has taken a concrete step into the rare‑earth elements space through its partnership with Rainbow Rare Earths. On September 7, Rainbow announced the commencement of a pre‑feasibility study (PFS) for the Uberaba project in Brazil, in collaboration with Mosaic. The study, early in development, is expected to be completed by the second half of 2027.

Details of the Collaboration

Under the Joint Development Agreement, SRK Consulting Ltd has been appointed to prepare the maiden JORC‑compliant Mineral Resource Estimate (MRE) for the Uberaba project. Mosaic is providing approximately six tonnes of phosphogypsum feedstock to Rainbow’s laboratory and pilot plant in South Africa for further testing. The project explores the recovery of rare‑earth elements from phosphogypsum, a by‑product of fertilizer production.

The initiative represents Mosaic’s strategic diversification, leveraging its existing phosphate operations in Brazil to explore value extraction from fertilizer by‑products.

Why It Matters

For Mosaic, this collaboration extends its vertical integration beyond fertilizers into critical minerals that are essential for energy transition and defense technologies. The Uberaba PFS potentially opens a pathway to monetize phosphogypsum, aligning with sustainability and circular economy trends.

The PFS is still in its early stages; though neither resource size nor potential economic viability are yet established, the move confirms Mosaic’s interest in tapping into rare‑earths as a new material opportunity.

Next Steps and Considerations

Interest in rare‑earth elements has been rising globally due to supply vulnerabilities and importance in high‑tech applications. However, the Uberaba project faces a multi‑year timeline and technical and regulatory hurdles before scale‑up. The PFS will determine whether the project advances to full feasibility, construction, or pilot stage.

While intriguing, this is not a near‑term earnings or production catalyst for Mosaic. It should be viewed as a strategic long‑term initiative that complements, rather than replaces, the company’s core fertilizer business.

Stock Perspective (MOS) – for Context

As of September 4, Mosaic’s stock price stood at $25.85, reflecting a +3.4% change. Investors should note that this share performance may not be directly linked to the Uberaba rare‑earths study—no immediate market reaction tied to the announcement has been established.

The PFS news offers a meaningful signal of Mosaic’s interest in rare‑earths and sustainability-driven projects, which may shape investor interest in the medium to long term.