In this paper, we present results of a study about the possibilities of utilizing talc ore mining tailings as a refractory raw material aiming at magnesium aluminate MgAl2O4 spinel composition. The mine tailings are rich in magnesite but contain also other minerals such as talc, chlorite, dolomite, and iron sulphides. As alumina source for spinel synthesis, we studied also another secondary raw material, an aluminium hydroxide precipitate, a by-product generated from the pickling process of aluminium anodizing. The goal of this paper is to study and compare a pure Mg–Al–O system and the corresponding Mg–Al–O system with some impurities. The formed phase and microstructures were examined by XRD, FESEM, and EDS studies. The thermal behaviour was studied using thermogravimetric analysis.
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