Fourier transform infrared spectroscopy (FTIR) investigation focused on Italian postage stamps in the course of time

Abstract

From the inscription of the General Post Office in Washington DC: “The stamp is the propagator of news, links between distant families, messenger between friends, solace in solitude, a vehicle for commerce and industry, an element of human progress, promoting brotherhood, peace, goodwill among men and nations”. It’s hard to imagine how much history can be held in a small piece of paper and how many purposes this little object was destined to have. This is why postage stamps have reached so much importance and interest, which they began to be considered as work of art actually. In order to see beyond the careful eye of the philatelist, FTIR (Fourier Transform Infrared Spectroscopy) in ATR (Attenuated Total Reflection) mode has been successfully employed in material characterization of many stamps. Samples since 1861, year of the unification of the Kingdom of Italy, until to date, across a vast philatelic collection, has been characterized in this study. The immediate response of this type of spectroscopic technique let to achieve significant data information, which led to design history changes in paper making technologies. The first mail stamps published in Italy portrayed King Vittorio Emanuele II and it showed to be made of sheet of cellulose paper. Going forward in years, many differences were detected in paper composition. The mail stamps were also observed by fluorescence microscopy, in order to determine differences in the application of fluorescence. The analyses were performed without any alteration of the samples and no removal of material was needed, which represents the “conditio sine qua non” for investigations on these kinds of Cultural Heritage.