Silk-facing Fungi

Silking, a conservation technique which involved gluing a silk gauze over the face of a manuscript, was popular in the mid-20th Century, especially for treating early Chinese documents. The method is now little used, and the question as to whether silking interventions should be reversed is controversial, given the high economic cost of active intervention, and there are few scientific studies as to the long-term consequences of the technique. To start addressing this problem, silk-facing materials from documents of the Stein collection were analysed using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy. The diversity of contaminating microbes was unravelled through the combination of culture dependent methods and amplicon sequencing analyses. Here, we show that the silking method is affecting the overall integrity of the silk-faced manuscripts, principally due to physical abrasion and significant fungal contamination. Unless the silk facing is removed, irreversible damage to the documents is highly probable.