A depth profile‐scanning study of an 18th‐century gun‐powder horn as well as reference Baltic amber samples was performed using a Raman confocal microscope equipped with a 785‐nm laser. It was found that spectra collected from the surface are different than those from the bulk. The main changes are observed in the 1,700–1,400 cm−1 range and are caused by degradation of the amber. The degraded layer was characterized mainly by an increase of the 1,615 cm−1 band ascribed to the ν(CC) characteristic of aromatic rings and a decrease of the 1,645 cm−1 band ascribed to the ν(CC) of nonconjugated structures. The degraded layer is estimated at 100–150 μm, where the spectra gradually resembled the spectrum of nondegraded amber. Analogous changes were observed both for the reference samples and for the abovementioned historical object. The observed spectral changes suggest that this technique could be utilized for studying the degradation of amber artifacts in museum collections.

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