Abraham Lincoln's iconic silk top hat, which he was wearing the night he was assassinated, on display at Ford's Theatre in Washington, D.C.Jonathan Ernst / Reuters

Even in our fractious, ill-tempered times, we can all come together to agree on this: $6 million is a lot to pay for a hat. That’s true even if the hat is a stovepipe model that once belonged to Abraham Lincoln. If it turns out not to have belonged to Lincoln, well then, the $6 million really does begin to look like a serious extravagance. And if you borrowed the $6 million to pay for the hat that you later discover probably isn’t Lincoln’s, the whole deal could quickly swell from extravagance to calamity.

And so it might be doing now, in Springfield, Illinois, Lincoln’s hometown and the site of the Abraham Lincoln Presidential Library and Museum. Two years after the museum opened in 2005, its sponsoring foundation borrowed $25 million to buy the Taper collection, at the time the largest collection of Lincoln stuff in private hands. Louise Taper, the eponymous collector, had, over the previous 30 years, acquired artifacts that one expert refers to, in nontechnical language, as “the superstars.”

Among her 1,500 items were Lincoln’s billfold and his eyeglasses, his favorite pen, and the gloves he wore to Ford’s Theatre the night of his murder, still flecked with blood. She owned the earliest known sample of his handwriting, a leaf torn from a schoolbook. She even owned the chamber pot he used in the White House. And the hat too—as inseparable from the Lincoln image as the whiskers, and one of only three, it was said at the time, that were known to have survived from his day to ours. An assessment placed the value of the hat alone at more than $6 million.

Nobody back in 2007 thought $25 million was a pittance, but not many people said it was an extravagance either, at least publicly. Even in perpetually broke Illinois, times were flush; the Great Recession was a little cloud no bigger than a man’s hand rising from the cornfields. At a single stroke, the museum exponentially increased the historical value of its holdings, which until then had comprised mostly documents (including some superstars of its own—one of the five handwritten copies of the Gettysburg Address, for example). The museum was self-consciously cutting-edge in its computer-powered exhibits, using holograms and life-size re-creations and a relentless sequence of optical and sonic effects to divert the attention of visitors away from their cellphones. But the climax of the visitor’s experience was to be charmingly low-tech: a final, dimly lit exhibit called the “Treasures Gallery.”

The gallery, one of the museum designers told me, was modeled on the crown-jewels chamber at the Tower of London, with the important difference that these were crown jewels American-style. There were no rubied scepters or beaded orbs or sparkling tiaras, just the briefcase and notebooks and saddlebags of a 19th-century prairie lawyer, along with early printings or handwritten copies of his greatest utterances. In the innermost circle of the Treasures Gallery, the sanctum sanctorum, the holy trinity of Lincoln artifacts shone in pools of light: a signed copy of the Emancipation Proclamation, the Gettysburg Address in Lincoln’s hand, and, of course, the hat, a towering tube trimmed in beaver skin, with two small ovals worn away on the brim, presumably from Lincoln’s fingers as he tipped it to passersby or held it fast against blowy days.

For a book I was writing, not long after the museum opened, I spent an hour at a time in the Treasures Gallery watching visitors come and go. Not often, but often enough to notice, a man or a woman fresh from the high-tech fantasia of the previous galleries would suddenly confront the plain reality of these objects and be brought to tears. As a rule, visitors lingered in this gallery of relics longer than in any other. None that I spoke with ever seemed daunted when I told them the price of the hat.

The word relic is the key, redolent of the near-mystical reverence in which generations of Americans have held Lincoln. The Catholic Church, which has more experience with the veneration of physical objects than anyone else and has, as is its custom, surrounded the practice with a rubber-band ball of complicated rules accrued over centuries, divides its saintly relics into three classes. The first comprises physical remains of the beatified. The second deals with objects the saint used or wore. The third involves anything that has come into prolonged contact with the second class.

In the cult of Lincoln—which started before his body cooled on the morning of April 15, 1865—relics of the first class are relatively rare: The most obvious are tiny fragments of his skull, collected during his autopsy by the surgeons who tried to pry loose the bullet that killed him. They are kept and occasionally displayed at the National Museum of Health and Medicine in the Washington suburb of Silver Spring, Maryland, where they draw fans who are equal parts ghoul and Lincoln buff. Purported samples of Lincoln’s hair, allegedly clipped on his deathbed or during the autopsy, come on the private market now and then, but invite skepticism from serious collectors. “If every lock of Lincoln’s hair out there was genuine,” one avid collector told me the other day, “the man would have been a woolly mammoth.” (Like the other sources I spoke with for this story, this collector did not wish to be identified by name; the world of Lincolnalia is, as he put it, “too small and incestuous” to risk the loss of any relationships, commercial or otherwise.)

Of course, such objects, when they do go on the market, are priced beyond the reach of nearly everyone, so the market has responded as markets do: It has expanded the definition of desirable Lincoln objects beyond the first, second, and third classes to the 48th class, the 87th class, the 94th class. The demand for Lincoln memorabilia, collectors say, never flags. Depending on the day, a scroll through the Lincoln pages on eBay will bring come-ons for old matchbooks from the now-defunct Lincoln Life Insurance Company, old lithographs, new copies of old lithographs, playing cards, every species of folk art, bubble-gum cards, sheet music, and … did I mention the matchbook covers? Six dollars apiece.

Perhaps most remarkable of all is the market in Lincoln forgeries. If you can’t afford a real, verifiable Lincoln signature (starting perhaps at a couple of thousand dollars), you might want a fake Lincoln document, complete with a fake Lincoln signature, if it can be shown to be from the pen of Joseph Cosey, Charles Weisberg, or another of a handful of highly skilled forgers who flourished in the early years of the past century. Mark Hofmann, the world’s most celebrated living forger, who’s now serving a life sentence in a Utah prison, specialized in faking documents associated with the Mormon Church. But he also dabbled in Lincoln, and samples of his work occasionally stir the market and excite collectors.

Caveat emptor, however. “You just have to make sure it’s a real forgery—a real Weisberg or Cosey,” that avid collector once told me. “The market’s so hot now, we’re seeing a lot of fakes.”

But the museum’s Lincoln hat—this object capable of holding grown men and women in thrall, moving some of them to tears—is it a fake too? The first public suggestion that it might be came from a tireless reporter, Dave McKinney, then with the Chicago Sun-Times. Nosing around, McKinney discovered that historians at the museum had, over time, given different stories of the hat’s origins—its “provenance,” as the trade calls it.

The hat had been passed down through a family of farmers from downstate Illinois. The family sold it for an unknown price to the state’s official historian, James Hickey, in 1958. An affidavit accompanying the sale, written by the original owner’s daughter-in-law, said that Lincoln had given the hat to her father-in-law when he visited Lincoln in Washington in 1861. In 1990, Hickey sold the hat (again, price unknown) to Louise Taper, who occasionally lent it out to special Lincoln exhibits. By this time, Hickey’s successor was describing the hat as the one Lincoln had worn “during the Civil War.” In 2012, five years after the state had bought the hat as part of the Taper collection, another historian for the Lincoln library offered still another version of the provenance. He told McKinney that Lincoln had probably given the hat to the downstate farmer at one of the Lincoln-Douglas debates in 1858.

Because no one could show that the farmer had ever traveled to Washington during the Civil War, the library historian told McKinney, “I guess you’d say we’ve taken something of a historic liberty in redating it to a much more plausible time and place.”

The hat’s defenders point out that the hat is in Lincoln’s size. It was likely made by a Springfield haberdasher during Lincoln’s time there. Beyond those claims, the trail goes cold. Even after McKinney’s first story ran, the museum continued to show the hat periodically in rotation with other artifacts, with no mention of its dubious provenance. The visitors continued to come and go, to stand before the relic and marvel. The foundation’s website still offers a clickable, 3-D image of the hat.

Now at WBEZ, a public radio station in Chicago, McKinney has stayed on the case. In September, he reported on a “highly secretive effort to authenticate the hat” by the Abraham Lincoln Presidential Library Foundation, which had taken out the loan to buy the Taper collection. The effort, begun in 2013, failed. It involved DNA tests by forensic analysts from the FBI, which found no evidence of Lincoln’s genetic material, and a study of the provenance by two historians, one from the Smithsonian and another from the Chicago History Museum.

“The current documentation,” the historians concluded, “is insufficient to claim that the hat formerly belonged to President Abraham Lincoln.” They recommended that the museum remove the hat from display until further research could establish its authenticity.

As it happened, the hat was off display when McKinney’s story aired on WBEZ. Museum officials said more research was already under way to authenticate the hat, and until the project was finished, the hat would remain in the vault.

Meanwhile, the foundation is struggling to pay off the roughly $9 million remaining on the original loan, which comes due in October. The Taper collection is the loan’s collateral and would be forfeited with a failure to pay; an auction would be held, and the collection would scatter. The state government is broke and says it can’t help. The foundation, says its vice chair, Nick Kalm, is pursuing “traditional outreach to high-net-worth individuals and foundations” to raise the money quickly. Among its other efforts is a GoFundMe page, which so far has raised nearly $35,000 toward its $9.7 million goal.

“We are going to do everything in our power,” Kalm says, “to raise enough money to work with the bank so that none of the core holdings in the museum ever see the auction block.”

In Illinois, they’ve coined their own word, hinky, to describe the irregularities—sometimes amusing, sometimes appalling—that characterize the way official business is conducted in the state. There is much about the tale of the hat that is hinky. You could begin in 1958, with the obvious conflict of interest involved in a state historian using his position to buy an apparently invaluable artifact for his own use.

On the other hand, we could also be looking at something more innocent, and more telling—a case of mass, mutual hypnosis, a will to believe so deep-seated that it overpowers any inclination to skepticism, even among men and women trained to be skeptical. Catholics will tell you that relics have a practical, theological point to them. They are a rebuke to the tendency to spiritualize the saints, to think of them as spectral beings, somehow removed from the world. Physical relics impose on believers the reality that saints were bodily creatures, just as they are.

Lincoln wasn’t a saint, of course—he probably wasn’t a Christian either. Yet for many of us, his historical importance and personal greatness are so vast that we risk untethering him from the real world. The Lincoln museum is testimony to his role in American history, a role like no other. How invigorating it is to move through the exhibits in Springfield as the evidence of his greatness piles up and, at the end, to come upon something of his own, a relic that might carry over the reality of a man: a book or a belt or a pen. Or a hat.

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