<p>The growing demand for clinker ceramics in Russia, driven in part by import substitution policies, has intensified research into raw material compositions and processing conditions. Clinker ceramics are designed for use in aggressive environments and exhibit properties comparable to high-strength concretes. This research investigates the relationship between raw material composition, granulometry, and firing regime on the mechanical performance of clinker ceramics. The ceramics were produced under laboratory conditions from Siberian fusible and refractory clays with the addition of albitophyre as a sintering aid. The objective was to develop a composition for clinker ceramics with a water absorption index of 4%. Results demonstrate that the granulometric fraction of albitophyre significantly influences density, porosity, and sintering quality. Fine fractions (&lt; 0.5 mm) promoted the formation of a stable framework structure, reducing porosity and improving compressive strength, while coarser fractions (0.5 – 2.5 mm) increased water absorption and reduced strength. The findings highlight the importance of optimizing additive granulometry and firing parameters to achieve clinker ceramics with low water absorption and high mechanical reliability.</p>