Stabilizing a Ceramic Jug

This small ceramic jug had been partially reconstructed in the past. However, it was sent to us for conservation because unfortunately one of the previous joins had failed, causing a large sherd to detach.

Before Conservation

As we can see from the photos below, this sherd only connects to the rest of the jug along one edge, as there is a gap along the top where other fragments are missing. Joins like this, where all the weight is placed on one join, and the gravity force is perpendicular to the direction of the join, are generally more prone to failure compared to joins at the top or bottom of sherds, where gravity is parallel to them. This is due to the fact that most adhesives are stronger when pulled across, then if they are slid along or twisted.

For this reason, our conservators decided that simply re-adhering the sherd via the the old join would not provide enough support, as the same issue may occur again the future. A fill was therefore constructed, allowing the sherd to join to the sherd above, and providing additional support from another direction. To do that, our conservator first re-adhered the sherd to the jug via the old join; she then applied dental wax to the back of the gap at the top of the sherd, creating a backing mould. An adhesive mixture was then poured into the gap to fill it and create a strong bond.

After drying, the dental wax was removed, and the fill was shaped using solvents and small hand tools to match the thickness and texture of the jug, and coloured to blend with the rest of the jug.

After Conservation