A presentation sword given to Lafayette, a French general known as one of the great heroes of the American revolution, is valued at $40,000-50,000.
The lot will auction at Early American in Santa Fe, California on August 23.
It features a curved blade inscribed with "Honneur au Gal: Lafayette" and "Chartre u Liberte".
It's thought to have been made for the general's return to the US in 1824, when he took an extended tour of the nation as the guest of president James Monroe.
Lafayette (1757-1834) joined the revolution in 1777, evading capture while crossing the Atlantic by disguising himself as a woman.
He proved a useful ally to the continental army, both as a general and in his ability to negotiate aid from the French government.
A letter written by George Washington in 1778 is another highlight.
The lot concerns Thomas-Antoine de Mauduit du Plessis, another French officer serving the Americans.
It reads in part: "The Chevalier (Thomas Antoine) Mauduit Du Plessis will have the honor of delivering you this letter.
"In expectation that the war is at a conclusion in this Country and that another is kindling in Europe; he has determined to return to France to offer his Service to his own Country.
"He waits upon Congress to obtain their concurrence for this purpose."
Washington believed at the time that the war was coming to a close and allowed Thomas-Antoine to leave. In fact, it would drag on for another three years.
We have a genuine strand of George Washington's hair available.
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