Amorphous structure and thermoluminescence characteristics of moldavites from Lower Silesia (Poland) and an indochinite from China

• Comparative structural and luminescence analysis was performed on Moldavites and Indochinite using XRD, FT-IR, 29 Si MAS-NMR, LIBS, and TL techniques. • Moldavites exhibit higher potassium and aluminium content, while Indochinite contains more silica and hydroxyl groups, affecting structural organization. • Beta irradiation induced significant changes in vibrational bands, revealing the formation of non-bridging oxygens in the tektite glass network. • Moldavite_2 and Indochinite show shell fractures typical for glass, while Moldavite_1 exhibits a mosaic texture. • The investigated tektites exhibit sub-linear thermoluminescence response in the range 0.5 – 100 Gy. Tektites provide distinctive evidence of the intricate mechanics involved in impact processes, even though the exact mechanisms behind their formation are still not fully understood. To expand knowledge about the types and differentiation of tektites, we conducted comparative studies of the texture, chemical composition, structure, and luminescent properties of tektites from Central Europe and China. We studied two Moldavites and Indochinite using XRD, FT-IR, microscope with element analysis (LIBS) and 29 Si MAS-NMR. Thermoluminescence (TL) glow curves were measured after beta radiation up to 200 Gy. The analysis focuses on differences in texture, chemical composition, and structure. The structural studies show the presence of water (-OH groups) in Indochinite and its lack in Moldavites. The higher content of silica in Indochinite induces the partial coordination Q 4 units which are not obserwed for Moldavite.