Rare Earth Elements (REEs) are critical for developing 'green' technologies and renewable energy supplies, as well as various high-tech, civil, and military applications. Their growing demand, particularly for Heavy REEs (HREEs) like dysprosium, is outstripping current global supply, leading to a worldwide search for new sources.Phosphorites, which are phosphate-rich sedimentary rocks containing over 18–20% P2O5, are currently the world's principal source of phosphorus for fertilizer. The primary phosphate mineral in phosphorites is carbonate fluorapatite (CFA), also commonly known as francolite. Recent research has identified phosphorites as an important potential source for industrial REE supply.The Georgina Basin Discovery – A Game Changer:Location and Age: Our focus is on the Cambrian (approximately 505 million years old) phosphorites located along the eastern margin of the Georgina Basin in northern Australia, an intracratonic basin covering about 330,000 km².Unexpectedly High REE Concentrations: These Georgina Basin phosphorites can contain up to 0.5 wt% REE, classifying them among the most REE-enriched phosphorites globally. This finding contradicts earlier global assessments that suggested Cambrian phosphorites generally had poor REE endowment.Regional Variations: REE concentrations in the Georgina Basin vary by orders of magnitude across its northern, central, and southern parts.Southern Prospects (Ardmore, Duchess, Phosphate Hill) exhibit significantly higher REE concentrations (mean 563-1689 ppm) and are enriched in elements typically found within the carbonate fluorapatite lattice, such as P2O5, CaO, Na2O, Sr, and possibly Ba. Ardmore, in particular, shows the highest total REE content, ranging from 809 to 5333 ppm.Central and Northern Prospects (Lily, Sherrin Creek, Barr Creek, DTREE, Paradise South, Paradise North) generally have lower average REE concentrations (mean 175-583 ppm) and a greater contribution of terrigenous material, characterized by higher concentrations of elements like SiO2, TiO2, Al2O3, and K2O.Seawater-Like REE Patterns: Despite the concentration differences, phosphorites from all prospects display REE patterns similar to modern seawater, featuring negative Ce anomalies, positive Y anomalies, and enrichment of MREE and HREE relative to LREE. This suggests that seawater was the major supply of REEs into these phosphorites.Conclusion and Future Outlook: The Georgina Basin phosphorites represent a significant and easily extractable source of REEs, particularly HREEs, which are highly critical for emerging technologies. The ease of REE extraction using processes similar to existing phosphate fertilizer production makes them highly attractive, presenting fewer technological and environmental challenges than many conventional REE deposits. The studies highlight that local geological conditions and depositional environments are key indicators for prospectivity, emphasizing the need to look beyond global secular seawater chemistry for exploration. Other contemporaneous deposits in the Georgina Basin, especially along the Alexandria-Wonarah Basement high, may also hold similar REE mineralization potential.Sources:The aqueous geochemistry of the rare earth elementsREE enrichment of phosphorites: An example of the Cambrian Georgina Basin of AustraliaRare earth elements in sedimentary phosphate deposits: Solution to the global REE crisis?Extraction of rare earth elements from waste products of phosphateCarl Spandler presents 'Rare Earth Element potential of phosphorites of the Georgina Basin'Recovery of Rare Earth Elements in The Hydrometallurgical Processes of Phosphate Rock- A Critical ReviewGeochemical and Isotopic (Nd, Sr) Tracing of the Origin of REE Enrichment in the Cambrian Georgina Basin PhosphoritesDisclaimer:AI generated content created using Google's NotebookLM.

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