Vatican removes salty white film coating Michelangelo's 'The Last Judgment'

VATICAN CITY — Michelangelo's "The Last Judgement" is getting a facial, with restorers removing a chalky white film of salt that has accumulated over the Renaissance masterpiece since its last major renovation three decades ago.

The Vatican on Saturday gave the media a sneak peak to the cleaning operation, which is taking place on a floor-to-ceiling scaffolding that has obscured the imposing fresco of heaven and hell that dominates the front of the chapel.

The cleaning operation is expected to be completed by Easter, in the first week of April. The public can continue to visit in the meantime, but will have to settle for a reproduction of “The Last Judgment” superimposed on a screen that covers the scaffolding.

Vatican Museum officials on Saturday described a simple but important cleaning operation to remove the white film of salt that has accumulated on the fresco thanks to the nearly 25,000 people who pass through the Vatican 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, in charge of the scientific research team at the Vatican Museums that is overseeing the cleaning.

Climate change also has a role to play, since the visitors who do come tend to sweat more, creating even more humidity that reacts with the fresco, he said.

Vatican Museums chief Barbara Jatta described the film as a “cataract” that is easy enough to remove: Restorers dip sheets of Japanese rice paper into distilled water and apply them to the fresco, and carefully wipe away the salt film.

Viewed up close on Saturday on the scaffolding, the difference between before and after is remarkable: Sections of the fresco that haven’t been cleaned look as if they are coated in a chalky dust; the cleaned sections show the vibrant colors and detail of the original. On the figure of Jesus, for example, at the center of the fresco, a privileged visitor can see how Michelangelo painted his hair and the wounds of his crucifixion.

The Sistine Chapel is named after Pope Sixtus IV, an art patron who oversaw the construction of the main papal chapel in the 15th century.

But it was a later pontiff, Pope Julius II, who commissioned Michelangelo to paint the famous ceiling, the “Creation of Adam” showing God’s outstretched hand, between 1508 and 1512. A later pontiff, Pope Clement VII, commissioned Michelangelo in 1533 to return to paint “The Last Judgment.”

The other frescos of the Sistine Chapel, where Pope Leo XIV was elected in May, undergo yearly cleaning with restorers working at night on cherry-pickers that can be removed each morning before the public arrives.

But such machines can’t access all of “The Last Judgement,” since the fresco is located behind the altar, which is itself raised up marble steps. That logistical impediment required the mounting of a fixed scaffolding to access the full fresco to clean it.

The Sistine Chapel underwent a complete restoration between 1979 and 1999, when centuries of smoke, grime and wax buildup was removed. The Vatican has left small patches of the pre-restored fresco intact to show the difference, which are now visible on the upper floors of the scaffolding and show a nearly blackened wall.

Rather than radically reduce the number of visitors who can access the Sistine Chapel, the Vatican is studying ways to address humidity levels, through filtration systems and other technologies, so that the salty film doesn't form again.

___

Associated Press religion coverage receives support through the AP's collaboration with The Conversation US, with funding from Lilly Endowment Inc. The AP is solely responsible for this content.