Diffusion-driven Li isotope fractionation dataset

This dataset accompanies the manuscript “Kinetic isotope fractionation of lithium in granite–pegmatite systems: The role of diffusion at crystal–melt interfaces.” It includes compiled lithium concentrations and δ⁷Li values from granites and pegmatites worldwide, together with model outputs from equilibrium and fractional crystallization calculations and from diffusion-based boundary layer simulations. The dataset is intended to evaluate the origin of the globally observed inverse δ⁷Li–Li relationship in evolved felsic magmas and to test whether crystallization alone can reproduce this trend. These data provide the basis for the figures and quantitative interpretations presented in the manuscript.