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Cyflwynir y tudalen hwn yn Saesneg am nad yw wedi'i gyfieithu i'r Gymraeg hyd yn hyn.

Os hoffech i’r dudalen hon gael ei chyfieithu fel mater o flaenoriaeth, anfonwch gyfeiriad y dudalen hon at

Fresh light on stained glass window

03 Ebrill 2007

Cardiff archaeologists are to use modern technology in a study which could provide valuable new evidence in preserving medieval stained glass windows.

Professor Ian Freestone, of the School of History and Archaeology, has won a £130,000 grant to study the origins, composition and corrosion of York Minster’s Great East Window. The study could yield new insights into the composition of stained glass and help with conservation work across the world.

The researchers are taking advantage of a rare opportunity to study the Great East Window, one of the largest expanses of medieval glass in Europe. The window, which has 287 panels each containing hundreds of pieces of glass, is currently being dismantled for cleaning and repair.

Stained glass is under continual threat from the atmosphere. It can dissolve away over the centuries through the action of rain and condensation.

The research team will use a scanning electron microscope to study rates of corrosion in different colours of glass. They will also use state-of-the-art laser ablation plasma spectrometry from the School of Earth, Ocean and Planetary Sciences to examine the elements in the glass. This should help determine where John Thornton, the medieval craftsman who created the window, obtained his glass.

Professor Freestone said: "The dismantling of the Great East Window provides us with a unique opportunity for study. We hope to learn how the make-up of the glass affects the rate of deterioration. We also hope to link particular types of glass to particular sources and glaziers, and thus predict which windows are most at risk. In this way, we can help conservators around the world draw up a priority list of church windows most in need of attention."

The research project is a collaboration with the Department of the History of Art at the University of York and is funded by the Leverhulme Trust.