Waste porcelain tile polishing sludges result from sediments of the treatment plants of tile manufacturing industrial wastewater. These polishing by-products are essentially a mix of fine residues of the specific ceramic body and a coarse residue of the abrasive used for polishing the surface of the tiles. In the present work, it was studied the use of porcelain tile polishing sludges, as a raw material in manufacturing of aluminosilicate fireclay bricks to be used in fireplaces. In order to establish the feasibility of the process and to develop the addition conditions, a set of appropriate ceramic compositions of white and red fireclays was studied. Results showed that up to 10 % in weight of the basic raw materials could be preplaced by tile polishing dry sludges, without significant changes in the ceramic process and the resulting materials properties.