A process for upgrading waste powders of the mining industry containing iron oxides is described, which includes preparing a mixture containing powder based on iron oxides, an aqueous dispersion of a thermosetting resin and optionally carbon powder, and a catalyst of acidic nature; kneading the mixture at a temperature between 5 and 100° C. to form a homogeneous paste, and granulating such homogeneous paste at a temperature between 100 and 300° C., thus obtaining granules of powder based on iron oxides and optionally carbon powder bound by the resin that has been polymerized.