Experimental evidence reveals the mobilization and mineralization processes of rare earth elements in carbonatites
Abstract
Whereas the genesis of carbonatitic rare earth element (REE) deposits has long been a focus of study, the controls on mobilization and mineralization of REEs during magmatic-hydrothermal processes still remain open to debate. Here, we present our investigation of the dissolution and crystallization of REE (fluor)carbonate minerals in alkaline carbonate brine-melts up to 850°C and 11.6 kbar. Our results show that REEs are soluble in Na2CO3 brine-melts, achieving concentrations exceeding 8 weight % at temperatures above 650°C. The addition of calcium and/or fluoride has minimal impact on REE mobilization, whereas introduction of silica suppresses REE solubilities by half, due to britholite formation above 550°C. Upon cooling, sodium and REEs combine to crystallize in burbankite or carbocernaite in sodium-enriched brine-melts, even at fluoride saturation. However, while the brine-melts contain substantial ferro-or aluminosilicate, REE mineralization in fluorcarbonates occurs after sufficient sodium precipitation in alkaline silicate minerals, hence revealing how silicate and sodium carbonate govern REE mineralization.
Department(s)
Physics, Astronomy, and Materials Science
Document Type
Article
DOI
10.1126/sciadv.adm9118
Publication Date
7-5-2024
Recommended Citation
Mayanovic, Robert A.; Yuan, Xueyin; Yang, Zhiming; and Hou, Zengqian, "Experimental evidence reveals the mobilization and mineralization processes of rare earth elements in carbonatites" (2024). Faculty Scholarship. 342.
https://bearworks.missouristate.edu/articles00/342
Journal Title
Science Advances
