Conserving 20 Chinese dragon tiles
In 2006, 20 large Ming Dynasty tiles were donated to the British Museum. They required conservation and mounting prior to going on display in the Great Court. In 2007 a team of 10 conservators spent four months on this project.
The tiles were dirty, as they had been originally displayed outside, exposed to the elements. There were a number of missing petals and corners, as well as loss of glaze on the front. Cement from previous mounting was stuck to the back of each tile and had to be removed. It took a team of six conservators two weeks, working in rotation, to do this. Remnants of cement on the glazed surface had to be delicately removed using scalpels.
Some of the larger missing areas on the corners and petals were filled with dental plaster, using dental wax as a mould. All the fills are removable, and were stuck into position using an adhesive that conservators know can be removed easily at a later stage if required. The fills were then painted using acrylic paints that closely match the original colouring.
The back of each tile was consolidated (strengthened) with an acrylic resin and an extra layer of scrim cloth was added to allow easier release if the backing has to be removed in the future. Conservators will be able to inject a solvent along the edges of this layer, which would work into its centre and create a localised solvent atmosphere to help lift the tile away from the backing. Reversible conservation treatments like this are designed to preserve the original object until such time as the treatment materials fail or knowledge of materials and methods has advanced.
Each tile weighs 25-30 kilograms (between 55 and 65 lbs). They were mounted on to individual aluminium plates, which are light but strong, and adhered with an epoxy resin. Threaded holes were drilled into the plates for bolts to be attached, so that finally the whole tile sequence could be mounted on to a steel frame for display.