In this special column highlighting artefacts from the diverse National Collection, four conservators and one conservation scientist from the Heritage Conservation Centre share with us an artefact that speaks to them and the conservation process required for each unique item.
MUSESG Volume 14 Issue 1 – July 2021
Text by Berta Manas Alcaide, Senior Conservator (Objects)
Read the full MUSE SG Vol 14. Issue 1
This grindstone and roller set is part of the Tang dynasty (618–907) cargo found in 1998 in a shipwreck off Belitung Island, Indonesia. The artefact was possibly from the Dvaravati culture (6–11th century) in central Thailand. This indicates that the ship likely made landfall at ports in this region during its voyage. It also suggests that some of the crew might be Southeast Asian in origin.
After spending more than a millennium underwater, a lot of salt had accumulated on the items. The Tang Cargo Collection, as it is known now, was desalinated in 2003 before being donated to the Asian Civilisations Museum in 2013.
Despite the previous desalination treatment, however, soluble salts continued to crystallise, forming a distinctive white residue that was attached strongly to the stone surface. As the salts were visually distracting and the recurring salt crystallisation might lead to the disintegration of the stone, desalination was repeated in early 2021. Much like receiving a clay mask treatment, a wet paste was applied to the stone surface. As the paste dried, it absorbed the soluble salts close to the surface—a technique known as poulticing.
Desalination is a major topic of study for me, so I was very excited to work on the Tang Cargo Collection. The practical experience has been enlightening, continually challenging me to improve the desalination treatment of these artefacts.