This data packages contains the data from Umo et al. (2021), The Influence of Chemical and Mineral Compositions on the Parameterization of Immersion Freezing by Volcanic Ash Particles, J. Geophys. Res. Atmos.. The data as shown in Figures 4,5,8,9, and Tables 1,2, and Supplement Tables 1,2 are formatted in comma-separated values (csv).