NEW YORK (Reuters) - Two of America’s leading auctioneers of guns said they refused on ethical grounds to handle the sale of the 9 mm pistol that George Zimmerman used to kill unarmed black teenager Trayvon Martin.

The firearm is so toxic that another auctioneer, the man who sold the revolver used to kill John F. Kennedy’s assassin, said he would want no part of it had he been approached by Zimmerman.

Zimmerman, a onetime neighborhood watch volunteer, is trying to sell the Kel-Tec PF-9 that he used to shoot the black Florida teenager in 2012, a case that convulsed the country and ignited debates on race relations, gun control and American justice.

A jury acquitted Zimmerman, who was protected by Florida’s “stand your ground” self-defense laws.

Two auctioneers, Wes Cowan of Cowan’s Auctions in Cincinnati and James Julia of James D. Julia Auctioneers in Fairfield, Maine, both said on Friday that Zimmerman called their establishments recently hoping to consign the gun with them. Both turned him down.

Cowan said he never returned the call. Julia said he instructed his employees not to accept the gun.

“The man is despicable and I would have nothing to do with his gun,” Julia said.

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Cowan said: “Morally and ethically, no, I wouldn’t do it.”

Zimmerman could not be reached for comment, but told Orlando TV station WOFL this week the gun was his to sell and he would not be “cowed” by critics.

The gun may be valuable to history buffs, gun enthusiasts or opponents of the Black Lives Matter civil rights movement that Martin’s death helped spawn.

Others who apparently retain vitriol for Zimmerman have placed false bids on the gun in an online auction on the United Gun Group’s website, bidding it up to $65 million on Friday with bidder names such as “Racist McShootFace.”

Herman Darvick, a collector and auctioneer, said there was no such backlash when he helped Ruby’s brother sell the .38 Colt Cobra that killed Lee Harvey Oswald on Nov. 24, 1963, two days after the assassination of John F. Kennedy. The gun sold for $220,000 in 1991.

Darvick said selling the Zimmerman gun was outside the bounds of acceptable behavior.

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“No, I wouldn’t touch it,” Darvick said. “If anything, it should go to a black history museum. He shouldn’t get a penny for it.”

NEGATIVE PUBLICITY

Another antique gun dealer, who was not approached by Zimmerman, said he would turn it down just as he refuses to sell Nazi memorabilia.

Sean Rich, owner of Tortuga Trading and well known as an antique firearms consultant on the History Channel TV show “Pawn Stars,” said the negative publicity for an auctioneer would outweigh any profit.

“That’s one of the reasons I choose not to deal with Nazi material. You have to draw the line somewhere,” Rich said.

But guns used by gangsters and gunslingers from the past are more acceptable, the dealers said, in part because of the passage of time and the lore surrounding personalities such as Jesse James, prohibition-era bootleggers or Bonnie and Clyde.

Rarely do history’s most infamous guns go on sale. The Mannlicher-Carcano rifle from the Kennedy assassination is held at the National Archives. John Wilkes Booth’s Deringer, used to kill President Abraham Lincoln, is on display at the Ford’s Theater Museum.

The Deringer would get $1 million to $2 million at auction, Julia estimated. About 10 years ago, he sold the law enforcement rifle that killed outlaw Clyde Barrow for $69,000. He said he would have to think about selling Jack Ruby’s gun, given the chance.

That gun has belonged to South Florida real estate developer Anthony Pugliese III, who bought it at Darvick’s auction, but he had to give up formal ownership when he pleaded guilty to a fraud charge last year, according to Doug Marek, general counsel for his firm, the Pugliese Company.

Marek declined to say who formally owned the gun now but offered, “It hasn’t gone far.”

In any case, there are no plans to sell the gun, Marek said.

“Reportedly, it’s the most valuable gun in private possession,” Marek said. “It’s clearly worth millions.”