Dear Colleagues, The abstract deadline for Goldschmidt 2024 is March 29 (two weeks from now). We welcome your abstracts to the following special session Theme 4b: “Diffusion and kinetics in minerals and melts: new approaches, isotope diffusion, and diffusion chronometry” Please bring your new ideas (controversial ideas are welcome!), new data, new modeling, and new synthesis for a lively discussion! The description of the session: Diffusion studies are entering a new phase with the advancement of experimental, analytical, and theoretical techniques. For example, in addition to studies on elemental diffusivity, investigation of diffusive isotope fractionation in both melts and minerals is becoming more and more popular. In silicate melts, treating multicomponent diffusion in eigen-component space is being explored. More diffusion chronometry models have been developed and also debated. The purpose of the session is to bring together the community to discuss recent advances in diffusion and kinetics and to explore future directions. We welcome contributions around the general topics of the determination of diffusion data, diffusion modeling, kinetic data and modeling, and the implications for understanding processes and time scales of natural systems. Abstract contributions from early-career scientists and traditionally under-represented groups are especially encouraged. All the best, Conveners: Youxue Zhang Fidel Castro Megan Newcombe Peng Ni James Watkins