The study of lithium (Li), gallium (Ga), and rare earth elements (REY) within coal-bearing strata represents a cutting-edge concern in coal geology, ore deposit studies, and metallurgy research. With the rapid advancement of technology and emerging industries, the global demand for Li-Ga-REY has significantly escalated. Several countries worldwide are facing immense pressure due to shortages in Li-Ga-REY resources. Coal-associated Li-Ga-REY depositions have emerged as a pivotal direction for augmenting Li-Ga-REY reserves. To ascertain the enrichment distribution patterns and genetic mechanisms of Li-Ga-REY within the coal-bearing strata of the late Permian Heshan Formation in Wanfu mine, Xian’an Coalfield, Guangxi Province, this study carried out comprehensive testing and analysis on Li-Ga-REY enriched in the mineralized layers within the strata. The Heshan Formation in Wanfu mine presents four layers of Li-Ga-REY-enriched mineralization, labeled from bottom to top as mineralized layers I, II, III, and IV, corresponding to coal seams K5, K4, K3, and K2. These critical metals are predominantly hosted within clay minerals (kaolinite, illite/smectite, and chlorite). The enrichment of critical metals within the Heshan Formation is closely related to terrigenous detrital materials from the Daxin paleocontinent, volcanic detrital materials induced by the Emeishan mantle plume and the Yuenan magmatic arc. The accumulation of Li-Ga-REY and other critical elements within the mineralized layers is the result of inputs from terrestrial and volcanic detrital sources, interactions between peatification and diagenesis stages, and occasionally the input of metal-enriched fluids. In the mineralized layers I, II, and III, the content of lithium oxide (Li₂O) surpasses the boundary grade, and the levels of REY, Ga, and (Nb,Ta)₂O₅ are close to boundary grades, indicating promising exploration prospects. The Wanfu mine in the Xian’an Coalfield can be considered a primary target zone for the exploration and development of coal-associated critical metal resources in Guangxi.

As a rare metal, lithium plays a pivotal role in strategic critical metal mineral resources and is one of the critical metals for developing the contemporary social economy. The Li-rich layers in the Xian’an coalfield in Guangxi Province were taken as a typical study area in this research, the material sources of Li-rich strata were discussed, and the enrichment process of Li-rich layers was revealed through geochemical research methods. The coal seams in this area have abnormal enrichment points with high lithium content, but there is a certain inhomogeneity in the plane and longitudinal distribution. This research studies the causes and material sources around the multi-layer lithium-extruded layers in the longitudinal distribution of coal-based strata. Through mineralogy and geochemical research methods, this research shows that Li-rich mineralization results from the combined action of terrigenous material and volcaniclastic source inputs, water–rock processes, and fluid inputs. The Li-bearing rocks formed over three periods, which are the weathering, sedimentation, and diagenesis stages. Based on factors such as provenance and geological processes, this study analyzes the genesis of Li-rich layers and provides a theoretical basis for the future prospecting of lithium ore deposits.