Gray cast iron production is a complex process involving all branches of metallurgy and a wide range of activities. According to the market needs and the qualitative and quantitative requirements of the final product, the strategy of production is systematically planned and therefore material quality, the economically justified production technology, the composition of the charge material, the technological elaboration of the casting process and the final surface treatment of the castings. In the experimental part, the casting process and product properties were followed: the cast iron frame of gray cast iron quality EN GJL-200. The characteristics of the mould mixture used for the DISAMATIC® moulding line, the chemical composition of the melt, casting parameters, as well as mechanical and microstructural properties of castings in the raw (as-cast) and surface treated (enamelled) state were observed. The influence of high temperature in the enamelling process on the microstructure change and obtained mechanical properties of gray cast iron EN GJL-200 was determined.Enamelling results in an increase in the ferite ratio in metal matrix, part of perlite transform into ferrite and carbides experience decomposition. Such microstructural transformation resulted in reduced tensile strength and hardness of enamelled samples, as well as mixed tough – brittle fracture. Non-enamelled samples show a brittle fracture across the graphite lamellas andpartially across the mostlyferritic metal matrix.