47 uncertain due to the inadequacy of REE resources and various geopolitical issues. Therefore, explor- ing new and alternative REE resources worldwide is extremely important to maintain a reliable and steady REE supply. Currently, the global demand for REEs is skyrocketing, owing to their immense consumption in the advancement of modern high-tech and green technologies. EXPLORATiON FOR RARE EARTH ELEMENTS (REES) iN DiFFERENT GEOLOGiCAL FORMATiONS OF SRi LANKA AND THEiR RECOVERY POTENTiAL Rare earth elements (REEs) are widely attract- ing global attention due to their crucial role in the modern lifestyle, especially in the industrial advancement towards a green economy through renewable technologies. This particular group of metals consists of the 15 lanthanides, yttrium (Y), and scandium (Sc). There are two subgroups, namely light rare earth elements (LREEs) from lanthanum (La) to europium (Eu) and heavy rare earth elements (HREEs) from gadolinium (Gd) to lutetium (Lu) and Y (Fig. 1a). Generally, LREEs are more abundant in the mineral deposits when com- pared to more priced HREEs [1]. Currently, the global demand for REEs is skyrock- eting, owing to their immense consumption in the advancement of modern high-tech and green technologies. Global demand for rare earth oxides (REOs) has increased approximately from 156 to 208 thousand metric tonnes over the period 2017 to 2019, and it is forecasted to increase to over 304 thousand metric tonnes by the year 2025 [2] (Fig. 1b). However, the global REE supply is unstable and https://doi.org/10.31705/BPRM.v2.2021.4 Research Feature https://doi.org/10.31705/BPRM.v2(1).2022.13