“…A variety of natural minerals, such as amethyst [94], sapphire [95], stilbite [96], calcite, dolomite, quartz [97], clays [98], mordenites [99,100], cretaceous strata [101], and synthetic solids, such as ceramics doped with CuO, FeO and TiO 2 [102], silicas, silicates and other compounds with silica [103][104][105][106], different crystals [107][108][109][110][111][112] and polycrystalline structures [113,114], disordered materials [115], thin films [116][117][118][119][120][121], ferrites [122], metal fluorides [123][124][125][126][127][128][129] and solid solutions based on fluorides [130][131][132][133][134][135], was investigated by the TSDC method.…”