The Significance of Discovery of Ion-adsorption Heavy Rare Earth Ore in Southern China

In recent years, China has made substantial progress in the exploration of ion-adsorption rare earth ores. Key advances include the identification of such deposits within weathered crusts developed on metamorphic bedrock, as well as the documented co-occurrence of light and heavy rare earth ores in granite-derived regolith. District A in southern China displays extensive geochemical anomalies in the rare earth elements lanthanum (La) and yttrium (Y), which have led to the identification of several light rare earth element ores. To assess whether light and heavy rare earth element (REE) fractionation occurs in ion-adsorption REE ores of District A in southern China, systematic sampling was carried out across weathering profiles developed on granite and gneiss bedrock in both district A and district B. Subsequent geochemical analysis characterized the vertical distribution patterns of REEs within these profiles. Research findings indicate the co-occurrence of ion-adsorption light rare earth element (LREE) and heavy rare earth element (HREE) mineralization within granite-derived weathering profiles at both study sites. A systematic vertical shift from LREE-enriched to HREE-enriched zones along individual regolith profiles demonstrates pronounced geochemical stratification between light and heavy rare earth elements. Within the study region, the identified heavy rare earth element (HREE) ores are predominantly enriched in yttrium, lanthanum, neodymium, gadolinium, and dysprosium oxides—Characterizing a high-yttrium, low-europium HREE mineralization signature. This finding refines the regional rare earth exploration paradigm, with particular implications for the targeting of ion-adsorption heavy rare earth ores.