OPERATIONAL COST ANALYSIS OF AN ELEMENTARY EXTRACTION CYCLE IN A MARBLE QUARRY OF THE APUAN ALPS

The present study aims to define a new cost indicator related to the extraction and handling of marble in a quarry located in the Apuan Alps, northern Italy. The analyzed cycle includes all operations required to extract a standard block volume, cutting with wire saws and chain saws, overturning the bench, block squaring, and transport to the yard, carried out using six machines, both for cutting and material handling. The adopted methodology considers costs related to fuel and energy consumption, maintenance, operator wages, and depreciation, assessed for each machine based on their contribution to the extraction of 60 cubic meters of processed marble. Knowing the annual productivity of the quarry, it was possible to determine a unit cost index representing the total cost associated with the elementary cycle of extraction and handling. This indicator is proposed as a practical tool to assess the impact of each phase, identify inefficiencies, and support cost-reduction strategies, especially relevant in the transition toward more efficient and digitalized mining practices aligned with the principles of Industry 4.0.