Seite - 146 - in The Vienna Genesis - Material analysis and conservation of a Late Antique illuminated manuscript on purple parchment

146 The silver inks of the Vienna Genesis To evaluate the composition of an alloy possibly used in the production of the silver ink, the EDX analyses were recalculated excluding all elements that are not potential alloying partners of silver; the corresponding results for all sample positions are listed in Table 4 (normalized to 100 %). The potential alloying partners of silver – copper (Cu) and gold (Au) – are present only in some of the analyses (in 14 of 72 point analyses both Cu and Au, in 9 only Cu, in 7 only Au). All EDX analyses of silver ink up to now are surface an- alyses on samples whose surfaces are not clean but more or less contaminated by dust and organic matter. It seems likely that the presence of copper and gold might be due to con- tamination at the location of the respective analysis position. If a silver-copper alloy with low copper content was used for preparing the silver ink, the copper as the less noble metal could have been removed from the alloy by the corrosion process. Table 4: EDX results recalculated using only potential alloy partners of silver, percentage per weight, normalised to 100 wt%. Pos Ag Cu Au Pos Ag Cu Au Pos Ag Cu Au T2 a 1 100.00 T5 9 100.00 T6 b 3 100.00 T2 a 2 100.00 T5 10 100.00 T6 b 4 98.30 1.70 T2 a 3 100.00 T5 11 100.00 T6 b 5 98.28 0.80 0.92 T2 a 4 98.19 0.75 1.07 T5 12 100.00 T6 b 6 98.72 1.28 T2 a 5 100.00 T5 13 100.00 T6 b 7 97.93 0.88 1.19 T2 a 6 100.00 T5 14 100.00 T6 b 8 100.00 T2 b 1 98.85 1.15 T5 15 100.00 T6 b 9 100.00 T2 b 2 99.09 0.91 T6 a 1 100.00 T6 b 10 100.00 T2 b 3 98.11 0.95 0.94 T6 a 2 99.26 0.74 T11 2 97.82 0.35 1.84 T2 b 4 100.00 T6 a 3 98.26 1.10 0.64 T11 3 100.00 T2 b 5 100.00 T6 a 4 98.24 0.96 0.80 T11 5 100.00 T2 c 1 97.70 1.37 0.93 T6 a 5 97.22 0.95 1.84 T11 6 97.40 2.60 T2 c 2 98.16 0.92 0.92 T6 a 6 99.31 0.69 T11 7 100.00 T2 c 3 98.52 1.48 T6 a 7 100.00 T11 8a 98.63 1.37 T2 c 4 97.77 0.84 1.38 T6 a 8 100.00 T11 8b 100.00 T2 c 5 100.00 T6 a 9 100.00 T11 8c 96.70 3.30 T5 1 100.00 T6 a 10 100.00 T11 8d 99.01 0.99 T5 2 100.00 T6 a 11 98.55 0.87 0.58 T11 9 100.00 T5 3 100.00 T6 a 12 100.00 T11 10 100.00 Open-Access-Publikation im Sinne der CC-Lizenz BY 4.0