Behind the scenes at Chippenham Museum: Reconstructing Roman Ceramics
A number of Roman finds were recently uncovered in the back garden of Marc Allum, a specialist on the Antiques Roadshow, during excavations organised by Chippenham Museum volunteers Clive Green and Mike Stone.
Mr Allum kindly donated the finds to Chippenham Museum. The Friends of Chippenham Museum worked hard to raise funds for the conservation of one of the finds - a fine Samian ware bowl - and conservators at CMAS were privileged to undertake the reconstruction of this beautiful piece.
The Samian ware is an example of a Dragendorff type 37 bowl, suggesting it is Gaulish dating from c. AD 70-130. The bowl has intricate decorative panels with repeating motifs of Gladiators battling wild cats and a more risqué scene thought to depict the deity Bacchus.
The Samian ware was found in 51 fragments forming almost half the bowl. Due to the fine nature of the form and decoration it was decided to fully reconstruct the piece, replacing lost areas to give more complete impression of its original form.
The conservator worked hard to piece together all the fragments. Interestingly the way the ceramic had broken into layers reveals its method of construction. Samian ware with such detailed patterns was formed by pressing clay into preformed moulds. The ceramic has split along the lines of the layers that were built up.
Graham Taylor of Potted History (@Pottedhistory) has created replica moulds for the vessel and its decorative features in order to produce a facsimile using the same techniques.
Once the form of the original ceramic was determined it was possible to create an accurate profile from base to rim using measurements of the thickness of the ceramic fragments and the diameter of the base and rim, comparing these with known examples.
The profile was used to form an accurate core in clay to which the original ceramic could be secured. Plaster replacement fills were then ‘spun’ using the profile as a guide. It was decided to only replace larger areas and those smaller areas required for strength.
The profile required a little tweaking as the ceramic had sprung slightly. Clay shrinks when fired placing the vessel under tension. When a vessel is broken the pressure is released and some fragments may flatten out from their curved form. Pressure in the burial environment can also cause distortion of softened clay vessels. In reconstructing the Samian ware an average was approximated between the two sides of the original ceramic to provide a more balanced form.
Numerous drill holes were present through many fragments as well as part of a lead ‘staple’. These show that the item had been repaired a number of times in antiquity and imply that the bowl was a treasured item. These signs of repair were preserved without alteration.
Colour matching was a careful process with layers of a subtly gloss glaze built up to replicate the depth of the original Samian red. A block colour was used to provide a more sympathetic appearance for the fills while the decorative elements were not replicated to ensure the original material was clearly discernible.
The bowl along with other treats from the stores will be on display in the exhibition What’s in Store: Behind the Scenes at Chippenham Museum until April 23rd moving to permanent display later in the year.
Beth Baker, Senior Conservator
- Tags: Antiques Roadshow, archaeology, Bacchus, bowl, ceramic, Chippenham Museum and Heritage Centre, clay, CMAS, conservation, decorative, Dragendorff, firing, Gaul, Gladiator, Graham Taylor, Marc Allum, plaster replacement fill, Potted History, reconstruction, Roman, Samian Ware, Wiltshire, Wiltshire and Swindon History Centre