Textile conservation experts from the University of Bonn have been preserving the fragile silk textiles believed to have belonged to Saint Ambrose, the 4th century archbishop and patron saint of Milan, since 2014. Considered holy relics of the saint, the ancient silks are so delicate the team created a mobile conservation lab so they could be preserved in situ at Milan’s Basilica of Saint Ambrose. The process of cleaning damaging dust from the silk fibers using small brushes and miniature vacuum cleaners has taken years.
Now conservators have taken on the most daunting project of all: raising a pane of glass weighing 80 kilos (176 pounds) from the silk tunic it was meant to protect. The pane was supposed to keep the silk threads clean and allow the tunic to be displayed without damage, but instead the fibers formed undulations under the massive weight of the glass. The fine threads also adhered to the glass over the years, making it extremely difficult to remove the pane without tearing the tunic. Even simply moving the tunic still under glass into a space where it could be conserved required elaborate planning.
The silk tunic measuring an impressive approx. 170 x 280 centimeters was stored in a drawer cabinet in the gallery of Sant’Ambrogio. However, this room was unsuitable for the preservation work. The transporters thus packed the glass panes with the valuable cargo between two large wooden boards, and the huge artwork was then carried vertically along the narrowest, winding corridors into the basilica’s archive, which was transformed into a workshop for a month. “This transportation was highly risky,” reports the restorer Ulrike Reichert. In some places, the art transporters had to proceed millimeter by millimeter to ensure the transit was ultimately successful.
Once they arrived in the workshop, the six art transporters heaved the glass, silk tunic and wood sandwich onto a large table. The most dangerous moment of the preservation was now imminent. While the art transporters lifted the glass pane very slightly using suction handles, Ulrike Reichert used a flat stick to very carefully separate adhering parts of the silk tunic from the glass pane square centimeter by square centimeter. “This work took a long time – for the helpers, it was a feat of strength to keep the heavy pane in the air the whole time,” says Schrenk.
Once all the silk fibers were separated from the pane, the transport crew lifted the heavy glass slowly a centimeter at a time. If the suction cups had failed or the glass had broken, the tunic could have been irreparably damaged. Thankfully nothing went wrong. The glass lifted clean and the silk didn’t budge. The crew was able to quickly move the pane off the tunic and put it down.
The tunic can now be painstakingly cleaned as its brethren were. Once it has been fully cleaned and stabilized, it will be covered with a lightweight acrylic pane which will preserve the silk textile without forcing it to bear the weight of a grown man sitting on its chest for decades.