The aim of this project is to definitely demonstrate the possibility of synthesizing clinkers, a type of “yellow" pavers, which fully resemble the original historical pavement in Sofia in terms of composition, structure, appearance and mechanical properties. It is foreseen, after studying and characterizing different marl deposits in the country, to add up to 10% of suitable natural raw materials or industrial waste, rich in MgO and iron oxides, to the main marl clay. This will ensure the formation of the desired quantities and type of pyroxene and anorthite crystal phases, which explains the very good mechanical properties of this unique pavement…