Renovation on Michelangelo’s fresco removes salt layer caused by visitors’ sweat

Michelangelo’s famed fresco “The Last Judgment” is undergoing a new cleaning campaign, as Vatican restorers work to remove a chalky white salt film that has formed over the Renaissance masterpiece covering the entire altar wall of the Sistine Chapel.

The intervention marks the first restoration effort on the fresco since its major renovation three decades ago, according to Vatican media outlets.

On February 28, the Vatican offered journalists a preview of the delicate operation, which is being carried out from floor-to-ceiling scaffolding that currently obscures the dramatic depiction of heaven and hell dominating the chapel’s front wall.

The cleaning is scheduled to be completed by Easter, in the first week of April. In the meantime, visitors can still enter the chapel, though they must view a reproduction of “The Last Judgment” displayed on a screen covering the scaffolding.

Officials from the Vatican Museums described the procedure as straightforward but essential. The salt residue has accumulated partly due to the roughly 25,000 visitors who pass through the museums each day.

“This salt is created because, above all, when we sweat, we emit lactic acid, and unfortunately lactic acid reacts with the calcium carbonate present on the wall,” said Fabio Moresi, who heads the scientific research team overseeing the project.

He added that climate change is also contributing to the problem, as warmer conditions cause visitors to perspire more, increasing humidity levels that interact with the fresco’s surface.

Vatican Museums director Barbara Jatta likened the buildup to a “cataract,” explaining that it can be removed with careful technique. Restorers soak sheets of Japanese rice paper in distilled water, apply them to the painted surface, and gently lift away the salt deposits.

Reporters granted access to the site described a striking contrast between treated and untreated areas: the uncleansed sections appear dulled by a layer of chalky dust, while the restored portions reveal the vivid colours and intricate detail of Michelangelo’s original work.

By Nazrin Sadigova