The Lanthanide “Tetrad Effect” as an Exploration Tool for Granite-Related Rare Metal Ore Systems: Examples from the Iberian Variscan Belt

Highly fractionated granites and related magmatic-hydrothermal ore-forming processes can be traced by elemental ratios such as Nb/Ta, K/Rb, Y/Ho, Sr/Eu, Eu/Eu*, Zr/Hf, Rb/Sr. The lanthanide “tetrad effect” parameter (TE1,3) also a useful geochemical fingerprint of highly granites. This work assesses its application an exploration vector for granite-related mineralization in the Central Iberian Zone examining TE1,3 variations with different concentrations rare metals fluxing elements (such F, P, B). multi-elemental whole-rock characterization main Cambrian–Ordovician Carboniferous–Permian granite plutons late aplite–pegmatite dykes exposed across Segura–Panasqueira Sn-W-Li belt show that increase values co-vary magmatic differentiation metal-enrichment, being rocks most differentiated, metal specialized. Argemela Li-Sn-bearing Segura Li-phosphate-bearing deviate from this trend, displaying < 1.1, but high P2O5 contents. results suggest mineralized to peraluminous-high-phosphorus Li-Sn systems are typified whereas those associated (lepidolite) peraluminous-low-phosphorus Sn-Ta-Nb display > reaching 1.4 2.1, respectively.