Abstract Introduction An optimised analytical technique based on pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS) and derivatisation in situ with hexamethyldisilazane (HMDS) was used to study several archaeological and artistic amber objects. The aim was to verify the authenticity of the objects and to provide historical information regarding the geographical origin of the ambers, and thus reveal the trade routes between different ancient civilizations. Results Py-GC/MS using HMDS as a silylating agent enabled us not only to identify the geographical origin of the archaeological and artistic ambers as succinites, but also highlighted the degradation of amber objects revealing a lower abundance of free diterpenes on the surface. Conclusion This work demonstrates the capability of Py-GC/MS with silylation in situ to identify the geographical origin of archaeological ambers and to provide crucial information regarding their degradation process. The porous and rough appearance of the outer layer can be correlated with the higher lixiviation and to the evaporation of free diterpenes from the surface. The knowledge of the amber degradation mechanisms is crucial to select proper conservation-restoration methods.