The last time Carl Sferrazza Anthony saw what he calls the most valuable thing he owns, he was sitting at a corner table at a cafe in Washington, waiting for his udon noodle soup to arrive.
Mr. Anthony, a historian of presidential families, had just come from the White House Historical Association, where he had picked up an engraved card from an aide to Jill Biden, the first lady, who had signed it last year and had kept it at the White House with a promise to have her husband sign it.
Mr. Anthony has spent three decades collecting the signatures of presidents and first ladies on the card, which is engraved with an image of the North Portico of the White House. With the addition of President Biden’s signature, the card now had the signatures of eight presidents and eight first ladies — every one from the Fords to the Bidens, save for the Trumps, whom Mr. Anthony had yet to track down.
Sitting at a corner table at Teaism, a cafe across from Lafayette Square, Mr. Anthony opened the manila folder that held the card and took a photo of it inside a flimsy plastic sleeve. He texted the photo to his brothers and sisters.
“Keep it in a safe place,” his sister texted back.
After lunch, Mr. Anthony took the manila folder in hand and walked back to his hotel room less than a mile away. He went to admire the card and found it was gone — only the plastic sleeve and the manila folder remained.
“I almost thought, ‘Did I play some kind of trick on myself, or did fate?’” Mr. Anthony said in an interview on Tuesday, just over a week after he had lost on the card on July 24. “How in the world could this possibly happen? My brain exploded.”
Mr. Anthony said he had never had the collection appraised and had never thought of selling it, since he planned to keep adding signatures to it. Its value, he said, was mainly sentimental.
The signatures were symbols, Mr. Anthony said, of his diligence and the personal relationships he had forged with presidents and their spouses. The loss of the collection was previously reported by the Washington Post columnist Petula Dvorak.
“I am trying to be philosophical about it, given the scope of so many people’s problems, but it’s been pretty crushing,” Mr. Anthony said. “There must be a word to describe those peculiar things that happen to us as a result of the most mundane little mechanical intricacies of life.”
Brian Kathenes, an appraiser who specializes in autographs, manuscripts, rare books and historical documents, said that a color photo signed by four presidents — Gerald Ford, Jimmy Carter, George H.W. Bush and Bill Clinton — as well as six first ladies had sold at Sotheby’s in 2020 for $9,375.
Mr. Anthony’s signed engraving was “probably more valuable,” as some of the presidents have died, Mr. Kathenes said. “It’s a wonderful piece of American history that might be gone forever,” he said.
Mr. Anthony said he had bought the engraved card in the mid-1990s, with only President Ronald Reagan’s signature on it. He then had it signed by Nancy Reagan, for whom he had worked as a speechwriter.
The Clintons signed it at the White House in 2001. The Fords signed it later that year when Mr. Anthony visited them in Rancho Mirage, Calif.
He mailed it to George H.W. Bush and Barbara Bush, who mailed it back with their signatures and a cheeky note from Mrs. Bush chiding him for collecting the signatures out of order.
George W. Bush and Laura Bush signed it during a joint interview they did with Mr. Anthony in the Oval Office in 2004.
In 2009, an aide in Michelle Obama’s press office took the card from Mr. Anthony at a White House gate and carried it upstairs to where the Obamas were having dinner and then took it back down to Mr. Anthony with their signatures.
After he had collected the card with Mr. Biden’s signature at the White House Historical Association on Aug. 24, he said, he walked across the street to Teaism. He was holding the manila folder gently, careful not to crush the card inside, he said.
Mr. Anthony, who lives in Los Angeles, was in Washington to read and sign copies of his latest biography, “Camera Girl: The Coming of Age of Jackie Bouvier Kennedy.”
After lunch, he walked along H Street to St. John’s Church. It was hot, and he stopped inside for a rest and sat in a pew where President Lincoln had sat, in the back corner.
He then walked to McPherson Square, where he stopped to take a photograph of the equestrian statue of James B. McPherson, a Civil War general, with birds perched on its head. It’s possible the signed engraving slipped out there, he said.
He continued to walk to Thomas Circle, where he stopped to take another photo, this time balancing a bag of salty oat cookies from Teaism and the manila folder in one hand and his camera in the other. He thinks that was most likely where he dropped it.
When he got back to his hotel room, at 1400 M Street, Northwest, he went to admire the engraving again and saw that it was gone.
He immediately went back to retrace his steps. He spoke to employees at Teaism and to a homeless man at Thomas Circle. Workers at St. John’s Church reviewed security footage, he said. Nobody had seen the card.
Mr. Anthony posted a video about his lost collection on TikTok, hoping that might help.
He said he was also offering a reward for its safe return, although he declined to say how much. He still hopes it might be found, but is trying to keep his loss in perspective.
He said he had written a list for himself, reminding himself that no one had been hurt or killed.
“I think I feel better having lost this myself than I would had it been stolen,” he said. “And I remind myself that people lose all sorts of valuable things, including loved ones in floods and fires. I suppose, ultimately, on a certain level, this was just a piece of paper with signatures on it of people who were, and are, no more intrinsically valuable than any of us.”