THE USE OF NEAR INFRARED SPECTROSCOPY AS A DIAGNOSTIC TOOL FOR HISTORIC SILK ARTEFACTS

As a prestigious and expensive textile, silk is found in many historic artefacts of cultural importance. However, as silk ages it becomes increasingly fragile and thus prone to damage through handling, display or even conservation treatment; these problems are exacerbated by some of the processing methods traditionally applied to such materials. Therefore, in order to minimise the danger to these objects, it is vital to have a good understanding of the physical state of the silk component. It is shown that near infrared spectroscopy, in combination with multivariate analysis, provides a method of assessing the stresses within a silk artefact, thereby highlighting areas at particular risk and allowing informed decisions to be made as to the potential dangers of intervention. As near infrared spectroscopy may readily be used with a fibre optic probe, these analyses can be performed in situ, rapidly and in a non-invasive manner, thus allowing assessment to be carried out in collections and displays without requiring samples to be taken, limiting the disturbance to artefacts. Therefore, the technique provides a valuable tool to gain a practical understanding of the condition of silk artefacts, and a means of informing conservation, display and storage strategies.