Application of Fourier transform Raman spectroscopy to the characterization of parchment and vellum. II—Effect of biodeterioration and chemical deterioration on spectral interpretation

Raman spectra of ancient parchment and vellum were recorded and used to characterize materials used in early mediaeval (10th century) and later works. These studies support work on the characterization of pigments used on historiated manuscripts and provide the basis for future studies of the interaction between pigments, binders and parchment or vellum. Examination of the undecorated parts of manuscripts or books has been undertaken to ascertain if there are traces remaining of the procedures used to prepare the materials; in several cases, there is spectroscopic evidence for the presence of sulfates and slaked lime, which were used in the preparation of vellums for scriptoria. The deterioration of vellums and parchments has been related to spectroscopic observation of changes in the protein CONH structures and to the chemical destruction of the CSSC bonds of cysteine. Band broadening resulting from the chemical reactions at these sites was analysed.