This work presents the possibility of using a mixture of different mining and industrial wastes (fly ash, waste rock, glass cullet and waste solution as a binder) for ceramic aggregate production with the application of microwave radiation. The effect of the chemical composition of the raw material mix reflected by F/SA ratio (flux oxides/SiO2 + Al2O3) on the mechanical and microstructural properties of the aggregates was evaluated using X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), and X-ray nanotomography (nCT). A higher proportion of fly ash relative to waste rock in the mixture composition led to an increase in the F/SA ratio. The greater the F/SA, the higher the values of particle density and compressive strength, ranging from 1.72 to 1.87 g/cm3 and 6.31–7.31 MPa, respectively. Moreover, higher F/SA led to lower water absorption and porosity, which oscillated between 2.12 - 3.44% and 3.22–5.00%, respectively. X-ray nanotomography studies revealed an increasing contribution of larger pores with a radius of and an overall increase in porosity as the F/SA ratio rose. This finding was further confirmed by SEM investigations. TG-QMS analysis showed that organic matter could act as a pore-forming agent. The basic physical and mechanical paramaters of the obtained ceramic aggregates indicate the suitability of the studied wastes for the production of valuable construction materials.