The artist Maurizio Cattelan has created a solid-gold toilet for a Guggenheim Museum rest room. And, yes, it is fully functional. COURTESY DODIE KAZANJIAN

Five years ago, the artist Maurizio Cattelan announced his retirement from art by hanging virtually everything he had done—a hundred and twenty-eight startling objects and images—from the skylight at the top of the Guggenheim Museum’s spiral atrium. This week, in a small rest room about two-thirds of the way up the spiral, the Guggenheim installed the first work of his un-retirement: a celestially glowing, fully functional, eighteen-karat solid-gold toilet. When the work goes public on Friday, a uniformed guard will be standing by the door to answer questions, and also, shall we say, to discourage souvenir takers. A discreet label on the wall outside provides the title, “America.”

Not since Marcel Duchamp submitted a porcelain urinal for exhibition at the 1917 Society of Independent Artists show has a plumbing fixture been so ennobled. That one was never shown—the exhibiting committee decided to hide it behind a screen—but Cattelan’s will remain on view, and in use, for an indefinite period. Decades, maybe, if a donor can be found to buy it. The toilet seat is really heavy to lift, but that shouldn’t deter serious art lovers. Nothing Cattelan has done pre-retirement is more drop-dead beautiful, although his sculpture of Pope John Paul II lying on the floor in full papal regalia, felled by a jagged meteorite, comes close. And, for viewers who crave a one-to-one relationship with art, this piece cannot be topped.

Cattelan himself, tall and saturnine in slim jeans and a salmon-colored shirt, was on hand for last-minute activities on the day before the press opening. A film crew recorded a ceremonial cleaning of the sculpture by Richard Armstrong, the Guggenheim’s director. “I’m not very good at plumbing,” he said, grinning broadly. “What I cared about most was that it be intellectually defensible, and that it engages a big audience in a variety of ideas.” Cattelan was avoiding the camera. He kept putting his head around the screened-off area surrounding the rest room, urging people to use the fixture. (“You can be the first!”) The toilet is an exact replica of the one that used to be there, but it looks a lot more powerful. What Cattelan seemed to like best was its democratic appeal. “Whatever you eat, a two-hundred-dollar lunch or a two-dollar hot dog, the results are the same, toilet-wise,” he said.

Nancy Spector, the Guggenheim’s former chief curator, arrived with the artist Rirkrit Tiravanija. Asked if he would like to be the first to use the facility, Tiravanija smiled. “I actually need it,” he said. He entered the rest room and closed the door. When he came out, Cattelan asked him if the familiar experience had been different. “Exactly,” Tiravanija said.

Nathan Otterson, the museum’s senior conservator of objects, was asked about special maintenance problems for the new work of art. “Well,” he said, “we’re changing the cleaning materials we use normally. Someone from our regular cleaning staff will come by every fifteen minutes, and they’ll use special wipes, like medical wipes, that don’t have any fragrance or color or oxidizers. And we have a steam cleaner that we’ll use periodically. The color is going to change, and we’ll probably be brightening the toilet up with polish along the way.”

Cattelan put his arm around Otterson’s shoulder. “They’ll use Bulgari wipes, and Chanel powder,” he said. “Nathan knows everything about how to maintain this object.”

“We worked together on Maurizio’s 2011 retrospective,” Otterson said, looking very pleased. “I have experience with him, and a lot of problem-solving.”