Raman spectroscopy is presented as a suitable and fast non-destructive technique to obtain qualitative information about
glass samples of various origins (ancient and modern/industrial glass).
A first application is the broad corpus of archaeological window glass that still needs to be investigated. For many sites,
archaeologists have to deal with large collections of excavated glass samples and a selection of the most appropriate
samples for chemical analysis is necessary. A fast classification can be made based on Raman spectra: different kind of
glasses (Alkali-glass, High Lime-Low Alkali glass (HLLA)) have their own typical Raman signature. Even for glasses
giving strong fluorescence, a classification is possible after a simple treatment of the Raman data.
Raman spectroscopy has also been utilized to identify iron containing glasses. The effect of the iron content in glass
samples is reflected on the topology of the Raman spectra: a strong link between the ratio of the Q2/Q3 vibration units of
the silica tetrahedral structure is seen. Even (semi-) quantitative results can be determined from calibration lines if
matrix effects are taken into account (similar glasses). In amber colored glasses, an extra peak ~415cm-1 in the Raman
spectra indicates the presence of a Fe-S chromophore. Finally, in the fluorescent signals of some yellow and red glasses
two peaks of Zn-Se-Cd-S nanocrystals have been identified.
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