Frieze of Angels, detail

Effects of previous restorations

The cleaning campaigns in 1940 and 1953 caused some damage to the murals. This image shows how past cleaning abraded the paint surface. Recent examinations and analyses suggest that the 1953 restorers used a caustic wax-oil cleaning formula to clean and coat the mural surfaces, saturating the paint colors. Though effective in removing some grime, this treatment damaged areas of oil paint irreversibly.
Frieze of Angels, detail showing abraded red paint above the angel’s head caused by previous cleaning (1999 photo)
The Triumph of Religion