|Conservation of the St. Vitus Mosaic in Prague (1992–2008)
The mosaic is cleaned prior to application of the sol-gel protective coating. After extensive studies and testing, the cleaning method selected was one using a stream of compressed air and microscopic glass particles. The use of such particles, which are harder than the corrosion layer but softer than the mosaic tesserae, thoroughly removed the corrosion layer without effecting the glass surface. Photo: Dusan Stulik.