Abstract: The article provides an empirical method for using the number of violating reflections for the P4/nnc space group to estimate the formation temperature of different polytypes (P4/nnc, P4/n, and P4nc) of vesuvianite group minerals. For this purpose, a statistical approach based on an instrumentally investigated 197 samples of vesuvianite group minerals was used. As an example, the results of a study of a number of vesuvianite group samples from skarnoids of the Kovdor alkaline massif are considered. Crystal and chemical limitations of the proposed approach that are associated with the chemical composition and kinetics of crystallization of vesuvianite group minerals are also discussed. © 2025 Elsevier B.V., All rights reserved.