Colourless glass was popular during the Roman period from the late first century Ad and into the second century with production in volume for good quality tablewares. Its popularity declines in the late third century [1]. Antimony and manganese were used as decolorizers and four groups of colourless glasses are usually depicted in literature [2] those naturally decolored, those with the used of antimony, or manganese or those containing both Sb and Mn meaning recycled glass. We are developing a method based on photoluminescence to be able to sort quickly the colourless glasses according to the nature of decolorizers. The emission of Sb³⁺, Mn²⁺ and Fe³⁺ ions arises between 400 and 700 nm under the 266 nm excitation. Specific time resolved conditions were used to isolate the species. Our method was fixed and optimized by using as references some Roman glass samples analyzed by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICPMS) and reported in [3]. One interesting feature is that in addition to Sb³⁺, Mn²⁺ and Fe³⁺ emission, we can also detect Cu⁺ ions and Pb²⁺ ions. The identification of Pb²⁺ and Cu⁺ can be helpful for the recycling process study.
Some results will be given on colourless Roman glasses found in Reims in several worshops (mainly from the third century AD).
 
[1] Jackson C. M Archaeometry 47, 4 (2005) 763–780.
[2] Gliozzo E. Archaeol Anthropol Sci 9 (2017) 455–483
[3] Foy  D. et al. Archaeopress (2018) Roman Archeology 42 vol 2.