The damaging effects of mixed light-thermal ageing on parchment were studied by exposing mock-ups to artificial light (162 W/m 2 irradiance) at controlled temperature and relative humidity (52 °C, 30% RH) for up to 748 h, with testing being made during this time incrementally. The physical-chemical changes (deterioration) resulting from these conditions were analysed by applying FTIR-ATR and Raman spectroscopy, colorimetric measurements and MHT. The deterioration found includes the formation of collagen-destabilised intermediate states which then progressively convert to disorganised structures, e.g. pregelatinised collagen and gelatin. The process is characterized by molecular changes of collagen associated with its photo-oxidation. These are shown by changes in the position and intensity of the main FTIR absorption bands of collagen, namely those of Amide I, Amide II, and Amide III, as well as by the occurrence and the increase of a shoulder at 1740 cm −1. The shrinking activity of the collagen fibres in the parchment mock-ups was measured by the micro-hot-table (MHT) method, which revealed the presence of multiple collagen populations with distinct thermal stabilities and confirmed the deterioration pattern suggested by the molecular changes.
Two precious Carolingian manuscripts kept in the library of Kremsmuenster Abbey in Upper Austria were subject of investigation. The well-known Codices Millenarius Maior (Inv. No. CC Cim 1, Fig. 1a) and Millenarius Minor (Inv. No. CC Cim 2, Fig. 1b) were studied within the framework of the Centre of Image and Material Analysis in Cultural Heritage (CIMA) in Vienna. The manuscripts are especially famous for their precious and colorful miniatures of a very early medieval period. The aim of the work was the material identification (colors and inks) used for the make-up of the two codices in order to gain a better understanding of their evolution and their provenance. The instrumentation available in the CIMA laboratories allowed performing in situ measurements using non-destructive and non-invasive analytical methods. The investigations comprised a combination of three complementary methods: X-ray fluorescence analysis (XRF), Fourier transform infrared spectrometry in the reflection mode (rFTIR) and Raman spectrometry. In addition to the identification of the pigments and inks also a detailed characterization of the parchment concerning its manufacturing process was achieved by that combination. The identification of calcium carbonates on the surface of the parchment is an indicator for the liming or whitening of the animal skin, whereas the polishing process of the parchment surface with pumice stone, left traces of silicates, detected by rFTIR. The combination of XRF and Raman spectrometry enabled the characterization of black/brown inks in the text revealing the usage of iron gall inks. For the red inks applied for text and initials vermilion and red lead were applied in both codices. Furthermore, the pigment palette used for the illumination included: lead white, orpiment/realgar, red lead, vermilion and red iron oxides as well as azurite and indigo, together with the rather rare copper chloride hydroxide. Furthermore, in both gospels the application of metal leaves as well as powders made of silver-copper and gold-copper alloys could be determined by XRF on several folios.
Within an interdisciplinary project, preliminary results of which were published in 2007, a group of 65 silver coins (denarii) of Trajan, evenly distributed over the entire span of his reign (2nd to 6th consulate), as well as 3 coins from the reign of his predecessor, the emperor Nerva (AD 96-98), had been acquired on the coin market. These pieces could be cross-sectioned in order to carry out analyses. Measurements were performed with m-XRF and m-SRXRF to check the fineness of the denarius alloy as well as to investigate if the coins of the different consulates showed distinct traits concerning the main impurities which could suggest a change of ore sources. Furthermore, it was examined whether the influx of precious metals into the Roman treasury after Trajan's Dacian campaigns (AD 101/102 and 105/106) could have had any repercussions on the composition of the denarius alloy; comparative data was provided by the analysis of nine imitations of Roman Republican denarii presumably struck in Dacia. Documentation of the cross-sections was performed with SEM/EDX in order to clarify details concerning the specific microstructure of the coins. An enrichment of Ag of approx. 100 to 200 mm in the near surface regions of most of the coins could be observed, which is due to corrosion effects. Previous metallographic analyses done by several scholars had been inadequate to clarify the central numismatic and economic questions. With the presented analyses, it was possible to correct the results of the earlier research and to provide, for the first time, a secure basis of data for the investigation of the development of the silver alloy used for denarii in Trajan's reign.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.