Results of a comprehensive study of the material microstructure of refractory samples after service in a blast furnace with a useful volume of 2200 m3 for 14 years are presented. Structural and genetic analysis establishes a typical sequence of degeneration and wear processes of the ceramic furnace skull, including six stages: formation of micro-and macro-cracks; condensation of zinc vapor; zinc oxidation with formation of fire-resistant ZnO zincite and deposition of carbon black; chemical interaction of zincite with mullite and corundum to form ganite ZnAl2O4 and willemite 2ZnO·SiO2; partial oxidation of silicon carbide with the release of silica glass SiO2, eutectic melt of complex composition, and willemite. Due to intense accumulation of capillary pores, infiltration of molten slag into the volume of refractories does not occur. Wear of refractories within the furnace is a complex, mainly thermochemical mechanism, and a slow rate due to formation of a garnish containing refractory compounds. © 2023, Springer Science+Business Media, LLC, part of Springer Nature.