An interesting sword. It does not look like a repro but I'm not sure exactly what it is. The Medicus collection included a Tiffany-marked M1861 cutlass, but from the photo in the Fledermann book it is hard to tell details. I have also heard a member of the Sword Forum International site had an example in his collection, but he never posted a photo. I am fairly confident your cutlasses is not a wartime Ames product. First it lacks the Ames name and the inspection/acceptance marks found on wartime produced swords. (Granted these could have been worn/polished off or purposely removed.) Second, it lacks the serial numbers normally found on cutlasses made under Navy contract during the war. In June 1861 the Navy instructed Ames to serial number all cutlasses delivered. These are the numbers found stamped on the quillon in the format 12M/345. The sword with this marking would be the 12,345
th cutlass produced by Ames. The cutlass shown by UCV above is stamped 20M/95 which shows it was the 20,095
th cutlass produced for the Navy. (These numbers are often erroneously referred to as "rack numbers".) One occasionally finds unserial numbered cutlasses. Ames also produced 300 M1861 cutlasses for the Army which were not serial numbered but which were inspector marked "A.D.K.". The US Revenue Marine/Revenue Cutter Service (USRM/RCS) was the predecessor to the Coast Guard. During the CW it bought about 1000 Navy-style cutlasses to equip its cutters. It is believed these were also not serial numbered. Third, and in my view most important, Ames wartime cutlasses had 19 turns of wide on their grips; this cutlass appears to have only about 13 or 14.
Although most collectors think production of the M1861 cutlass ceased in 1864, in fact a small number were produced later in the century. These include the special-order cutlasses produced for the USS Niagara and USS Aloha around the turn of the century as well as the Medicus-pictured Ames Sword Co officer's cutlass named to Winfried Proskey. They were etched with the name of the ship or the officer, but no serial numbers. In the 1890s the RCS and the Navy also ordered a small number of additional cutlasses, all apparently completely unmarked. Finally New York and possibly other State Naval Militias ordered a small number of cutlasses for their units. Aside from markings (or lack thereof), the main difference from the CW examples is the number of turns of wire on the grips is reduced.
I suspect your cutlass may be from this later era and is probably an Ames product. If so, it may have been purchased through Tiffany, just as the Niagara cutlasses were procured through Hartley Graham, in which case the Tiffany markiings would be genuine. Alternatively, someone may have wanted to improve on unmarked Ames by stamping it with the prestigious Tiffany name. I tend to doubt this. The Horse Soldier Tiffany cutlass is quite different construction, and I have no idea why or for whom it was made. The blade etching appears to by a style found on late-century officers' swords.
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