Scientific study of an icon of St George and the youth from Mytilene
This small icon initially seems to be made in a typical way, with a wooden frame which is either part of the smoothed pine panel used for the painting (an integral frame), or made by adding an additional wooden piece (an engaged frame). However, close examination by British Museum scientists and conservators shows the frame is in fact made of strips of folded linen and parchment joined together.
This is very unusual but is remarkably similar to the frame on another small icon which comes from St Catherine’s Monastery, Sinai suggesting the two pieces were probably made in the same workshop.
Studies have shown that after the frame was constructed the whole surface was coated with a thick layer of gypsum (calcium sulphate) in a protein-based glue, and the image was drawn freehand onto this gesso layer.
Lines were also incised into the gypsum, following the outer edge of the image and the profile of the mountains in the background, marking the boundary between the area to be painted and area for the raised decoration. This raised decoration (known as pastiglia), also made of gypsum, was applied to the gesso covering the background and the raised frame to the very edge.
An infrared reflectogram (a type of photograph taken using infrared radiation rather than visible light) of the painting allows us to look through the paint to the initial freehand drawing where we can see a number of changes were made between this first sketch and the final picture.