light made solid

Here is an article with photos of a restoration project of windows from the Marienkirche in Frankfurt an der Oder.

During 2001 - 2002 the Laboratory for Scientific Restoration of Works of Applied Art restored 15 of 111 14th-century panels that made up three stained-glass windows in the Marienkirche (Church of the Virgin Mary) in Frankfurt an der Oder. Six centuries of pernicious atmospheric conditions, vandalism and war took their toll on the stained glass. In 1943 the panels were removed from the windows by the Germans to save them from bomb damage. They were placed first in the church itself and later in storage in Potsdam. From there they were removed to the Soviet Union and given for keeping to the Hermitage where they remained from 1946 to 2002. All the damage to the glass and lead came was recorded when they came into the museum.
The Hermitage had created in 2001 a Laboratory for the Restoration of Stained Glass with a team of three specialist restorers, three research workers specializing in mediaeval art and an expert in the chemistry of glass under the direct supervision of the museum's director.