NEW YORK >> It happened at 6 on a Sunday night. Adam — a strapping, 6-foot-3-inch marble sculpture by the Venetian Renaissance master Tullio Lombardo — fell to the ground on a patio at the Metropolitan Museum of Art, smashing into hundreds of pieces. "Nobody knew what had happened — it could have been foul play," said Jack Soultanian, a conservator who was called to the museum that night in 2002.

An investigation revealed that Adam’s plywood pedestal had buckled. "The head had come off," Soultanian said. "There were 28 recognizable pieces and hundreds of smaller fragments," he added, and skid marks on the torso where it slid across the patio floor. Philippe de Montebello, then the Met’s director, called it "about the worst thing that could happen" to a museum.

What followed was more than a decade of painstaking restoration that was unprecedented in the Met’s history. The project took so long there were rumors that the statue was beyond repair. But it wasn’t, as the Met will make clear on Tuesday when the museum not only puts Adam on display again but also releases videos of how Soultanian and his colleague Carolyn Riccardelli — with dozens of scientists and engineers — put the 500-year-old sculpture back together, relying on a radical approach to the conservation. Along the way, it made a visit to the hospital for CT scans. (Adam needed a nose job, as well as head, hand, knee and foot operations.)

The restoration project serves as a watershed of sorts for the Met, reflecting a new attitude adopted by museums around the world to share such innovative work not just professionally but also with the public. It is a dramatic reversal from decades past when museum conservators treated such efforts like state secrets, or subscribed to the belief that revealing a work’s history of damage would make it less beautiful to viewers. (Michele Marincola, a professor of conservation at New York University’s Institute of Fine Arts, recalled that the legendary conservator George L. Stout once compared discussing such restoration work to inquiring "about the digestive system of an opera singer." )

But today, "restoration is the cutting edge of art history," said Emilie Gordenker, director of the Royal Picture Gallery Mauritshuis in The Hague, whose museum is also planning a major exhibition centering on an in-depth restoration of a single painting, "Saul and David," which she described as riveting as a "crime scene investigation." Using the latest technology, the museum will chronicle the discoveries of its creation and history – every unexpected detail that lurks beneath the canvas, initially considered to be one of Rembrandt’s finest but later de-attributed. "We live in a time when the public wants to look behind the scenes, and museums are finally becoming more open about it," Gordenker said.

Italy’s Uffizi Gallery in Florence, for example, had conservators working in a glassed-in lab so visitors could watch the action. Right now, in Belgium, Jan and Hubert van Eyck’s "Adoration of the Mystic Lamb," better known as the Ghent Altarpiece of 1432 – one of the world’s most famous panel paintings – is undergoing a seven-year restoration. Financing from the Getty Foundation in Los Angeles has helped pay for it, including an interactive website showing the work in minute detail. (The public can also visit the three sites in Ghent where it is being restored.)

"This is a shift and I think a very important one," Luke Syson, the Met’s curator in charge of European sculpture and decorative arts, said of this new tell-all era. With Adam, he added, "there’s no pretending that the breaks aren’t there or that this didn’t happen. Yes, this awful accident occurred on our watch and now we are also responsible for its resurrection. Our processes need to be transparent."

In decades past, museums would have also restored a damaged work of art in a way that got it back on view as quickly as possible. In the case of a massive marble sculpture like Adam, they would have resorted to using multiple iron or steel pins that required drilling many of the sculpture’s joints. But such invasive work can be risky, curators said, potentially harming the marble.

Then there was the option, popular in the case of ancient sculptures, of leaving masterworks unrestored if they cracked with age, excavation or accidents – a process conservators often call "the romance of the fragment." That was the case with the Louvre’s headless "Winged Victory of Samothrace" or its armless Aphrodite of Milos, better known as the Venus de Milo. "There was a trend in conservation to take away all restorations from ancient sculpture and get down to the original fragment," said Riccardelli, the Met conservator who led the work on Adam. "But now we see the value of a Renaissance restoration."

Nobody at the Met thought the process would take 12 years. But de Montebello said then, and reiterated in a recent interview, that he wanted Adam "brought back to a state where only the cognoscenti could tell anything had happened."

"The aesthetic of Tullio is largely dependent on the high finish of the piece," he said. "To leave it in a broken state would have been to choose its accident as its defining historical moment."

The museum assembled a team of three conservators -Riccardelli, Soultanian and Michael Morris, who works independently – along with consulting scientists, engineers and curators. After Adam’s fall, conservators studied in depth how Tullio had created it – with a head of curly locks, a dreamy stare, leaning on a decorative tree trunk intertwined with a serpent and a grapevine. The sculpture, which dates from 1490-95, was originally commissioned for the tomb of a Venetian doge, Andrea Vendramin, and entered the museum’s collection in 1936.

Using a laser-mapping technology to create a three-dimensional "virtual Adam," the conservators and engineers were able to see the places within the sculpture that would bear the most stress when it was upright again. Fiberglass pins, an innovation in the field, tested best for weight-bearing and safety, and in the end only three – one in each ankle and one in his right knee – proved necessary to put Adam back together. Everything else could be reassembled using a newly developed, more pliable adhesive.

The last and final piece was the sculpture’s head, which was reattached on April 1, 2013. Since then, the entire sculpture has been cleaned, with the holes where the marble had pulverized filled in and colored to match the original stone.

When Adam goes back on view, some experts say, its accident will make it even more compelling to the public. "There’s the DIY factor," Patricia Rubin, the director of the Institute of Fine Arts, said. "It’s something everyone can relate to. What happened to this sculpture is a quandary you face each time you drop a piece of china in your kitchen and see it smash on the floor."

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