VATICAN CITY (RNS) – “The Last Judgment,” Michelangelo’s vast fresco painted into the plaster of the Vatican’s Sistine Chapel is undergoing an extraordinary maintenance process in preparation for Easter, with a team of 20 restorers working in two shifts a day remove a thin milky residue that has built up due to the thousands who come to admire the masterpiece every day.
Barbara Jatta, director of the Vatican Museums, described the coating as “a sort of cataract” to journalists on Saturday (Feb. 28) that flattens the dramatic effect of shadows and light of the roughly 45-by-40-foot fresco.
After it was discovered two years ago, laboratory tests revealed that the coating primarily consisted of calcium lactate, a type of salt formed from the breath of the 17,000 to 20,000 daily visitors to the chapel, where the church’s cardinals convene to elect a pontiff. Seven million people passed through the space last year.
“Calcium lactate comes from respiration, the increase in temperatures, humidity, and also the increase in the number of visitors,” explained Fabrizio Biferali, the curator of 15th–16th Century art at the Vatican Museums.
Details of the group surrounding Minos, with visible signs of removal of the whitish patina and restoration of the original chiaroscuro, in the Sistine Chapel’s “The Last Judgment” fresco. (Copyright © Governatorato SCV – Direzione dei Musei. All rights reserved.)
Michelangelo created the most famous image in the chapel, the Creation of Adam, in which God and the first man extend their fingers toward the other, in 1508, 25 years after the first Mass was said in the completed chapel. In 1533, Pope Clement VII commissioned “The Last Judgment” for the altar wall, though Michelangelo did not begin painting until 1536 under Pope Paul III, who named him “Supreme Architect.”
The fresco — a form of art in which pigments are applied to wet plaster, rather than painted onto dry walls — fills nearl …