Enrichment characteristics and sources of the critical metal yttrium in Zhijin rare earth-containing phosphorites, Guizhou Province, China

Yttrium (Y) is a critical metallic element that is used widely in modern scientific, technological, and industrial applications. Phosphorites in the Zhijin area of Guizhou Province, China, are famous for Y enrichment, but the enrichment characteristics and sources remain unclear. Previous studies suggested that the sources of rare earth elements (REEs, La–Lu) and Y (REYs, La–Lu+Y) were related to hydrothermal deposition. However, this study presents evidence refuting that hypothesis, with major and trace elemental data collected with quadrupole–inductively coupled plasma–mass spectrometry (Q–ICP–MS) analysis. These data show that Y in Zhijin REYs-containing phosphorites has a normal distribution and is particularly enriched relative to other REYs. The Y enrichment degree is different at different ∑REY intervals. Specifically, the Y enrichment degree is higher at lower ∑REY values and lower at higher ∑REY values. The REYs-containing phosphorites show features of primary phosphorites. Both REEs and Y have good correlations with P 2 O 5 in the phosphorites with low REYs contents (total REYs