Conserving Beirut's Shattered Glass

Stage three – beginning the restoration

Starting to dry reconstruct one of the vessels using Scotch tape.

Claire started with the Tier 1 objects. Before each reconstruction, Claire, who was already very familiar with the vessels, carried out additional puzzle work to make sure that she did not miss out any fragments for each individual vessel. This was a painstaking process. It was also important to clean the edges and surfaces with a 50/50 alcohol and deionised water solution to remove all the dirt, grease and previously applied conservation adhesives before the fragments could be dry reconstructed, first with Scotch tape. Dry reconstruction helps us see how well the fragments join together, as well as enabling us to gauge the number of missing fragments. However, we could only tape the fragments when the surfaces didn’t contain any archaeological deposits or layers of deteriorated ‘iridescence’ (where the surface of the glass has a rainbow-like effect).

Applying conservation adhesive to a fragment.

At the final stage, the fragments were adhered with a conservation adhesive. This part is particularly challenging. When glass breaks, original shapes and internal tensions that occur during manufacturing become severely affected. This means that when conservators reconstruct glass objects, internal tensions change, and the fragments may resist joining each other as they did in its original form. This is called 'springing'. The conservator needs to be extremely focused to achieve the best joins against all the stresses which glass fragments may present. Once this challenge is completed and the conservator is happy, then the objects are left for the adhesive to fully set before they can be handled again.

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