LA-ICP-MS U-Pb dating, chemical composition and evolution of oscillatory zoned andradite from the Chengmenshan Cu-Au deposit, Jiangxi province

•Incorporation of REE and U into andradite mainly follows coupled YAG-type substitution mechanism and the coupled substitution of [U4+]VIII + 2[Fe3+, Al3+]Ⅳ – [Ca2+] – 2[Si4+]Ⅳ in the dodecahedral position, respectively.•During skarn formation, the fluid evolved from pore fluid-mixed, through magmatic-hydrothermal dominated, to meteoric water influx.•The ages of andradite samples indicate that the skarn ore formation is coeval with associated granodiorite intrusions.