Seite - 46 - in The Vienna Genesis - Material analysis and conservation of a Late Antique illuminated manuscript on purple parchment

46 The parchment of the Vienna Genesis: characteristics and manufacture Thin sheep parchment prepared by the Late Antique method is very suitable for the application of different dyes. Both sides of the parchment accept the colour well. Cross-sec- tions of new parchment dyed with orchil demonstrate that the colorant penetrates the parchment, see chapter on purple dyeing. However, there are noticeable differences be- tween the way that the hair and flesh sides absorb the dye. The hair side has a slightly richer hue while the flesh side is often pale in colour and has a milky appearance (Fig. 11 in chapter on purple dyeing). Purple dye can be applied only to dry parchment that has been completely processed. Most likely, the finished parchment was roughly cut to size in order to avoid wasting precious purple dye on edges that would later be removed (Fig. 6). In this first step, the size of the sheet was kept larger than the final size of the manuscript bifolios. Purple dye can either be applied to the parchment surface in liquid form using a brush or the parchment can be immersed in a vat with the colorant, see chapter on purple dyeing. When the colour is sufficiently saturated, the wet parchment must be immediately re-stretched, otherwise it will become transparent and shrink. It is likely that pieces of dyed Fig. 6: The dyeing workflow. Newly made parchment is cut off the frame and roughly trimmed. Coloured parchment is stretched after application of purple dye and, after drying, cut to the final dimensions of the bifolio. (Depending on the quality of sheepskin one or two bifolios can be obtained from one skin.) Open-Access-Publikation im Sinne der CC-Lizenz BY 4.0