The Effect of Accelerated Alteration on the Discrimination between Baltic and Romanian Amber

Ten geological samples (five from each source—Romanian amber and Baltic amber) in duplicate for five different media (air, water, saline, acid and basic) were subjected to thermal alteration at 80 ± 2°C for 12 weeks, in the dark. The samples were analysed before and after the accelerated alteration experiment by Fourier transform infrared spectroscopy, both in transmittance and reflectance mode, and the acquired spectra were statistically processed by multivariate data analysis, mainly using principal component analysis. The results of the experiment are useful in giving a better picture of how to discriminate between archaeological amber artefacts.