In this publication optical spectroscopy is considered to be a supplementary technique to study ancient colored glass. It
results from a systematic study of the UV-VIS-NIR transmission spectra of intentionally colored glass fragments from
various archaeological and historical sites and dated from the Roman period to the 21th century AD. The main goal
consists of defining optical sensing parameters for this type of material. The considered colorants are iron, cobalt,
manganese, copper and chromium.
It is proved that many cases exist where optical spectroscopy can be seen as a straightforward, non-destructive, low-cost
and in-situ applicable technique in identifying authentic material or to obtain information about the origin of the material.
Possible sensing parameters are defined as the absence/presence of absorption bands characteristic for a specific coloring
metal oxide and the spectral position of these bands. These parameters could reveal information about the applied
furnace conditions and/or to the composition of the glass matrix. It is shown that the cobalt absorption band situated
around 535 nm for soda rich glasses (Roman and industrial times) is shifted towards 526 nm for potash rich glasses
(medieval and post-medieval times).
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