Seite - 144 - in The Vienna Genesis - Material analysis and conservation of a Late Antique illuminated manuscript on purple parchment

144 The silver inks of the Vienna Genesis Table 2: Samples for SEM/EDX. Sample num- ber Origin Description T2 a–c Vienna Genesis Silver ink, f4 T5 Vienna Genesis Silver ink, f4, page 8, line 1 right T6a, b Vienna Genesis Silver ink, f5, page 9, line 4 right T11 Codex Purpureus Petropolitanus f25, page 50, last line T17 Vienna Genesis f22, page 43, cross-section: parchment with silver ink Pe1 Vienna Genesis f22, page 43, parchment without ink from inner edge P1 Reference ink ST1_B LA-parchment, purple dyed, silver ink with sodium chloride and copper(1)oxide, polished, aged P2 Reference ink ST1_B See above P3 Reference ink ST1 See above, polished, unaged All samples were investigated in a FEI Quanta FEG 250 SEM in high vacuum mode (if not specified otherwise). X-ray micro analyses were performed with an EDAX system equipped with an Apollo X SDD detector. The samples were investigated in their state as delivered, no sample preparation was applied. Since in all samples from the Vienna Genesis the surface of the silver ink was contaminated with material consisting mainly of organic matter mixed with mineral particles, only point analyses were performed on spots where the surface of the silver ink appeared to be clean in BSE images. Results of EDX analyses containing all elements detected from three samples are pre- sented in Table 3 (normalized to 100 wt%, all figures are given in percentage by weight), the element patterns of these samples are representative of all other samples. The EDX results, which are only partly listed in Table 3, show that chlorine is present at each sample position in a percentage ranging from about 1 % to 20 %. Sulfur is present only at about 2/3 of total positions and in half of these positions with a percentage of less than 1 %. Therefore, it seems reasonable to assume that the corrosion of the silver ink is predomin- antly of chloridic nature. Table 3: EDX results containing all detected elements for three samples (point analyses), percentage per weight, normalised to 100 wt%. Pos C N O Na Mg Si S Cl Ag Ca Fe Cu Au T2 b 1 7.24 1.00 5.20 1.04 0.86 0.33 7.04 73.84 2.09 0.83 T2 b 2 8.74 1.44 5.82 1.09 0.30 1.35 4.12 75.07 0.55 0.66 0.64 Open-Access-Publikation im Sinne der CC-Lizenz BY 4.0