This a really interesting Colt Model 1851 Navy Revolver. I've seen and owned A LOT of 1851 Navies over the past twenty years but I have never seen one like this before. Aside from presentation and engraved guns, you see few Colts during the percussion era that show any special features. This one appears to have THREE:
1. For starters, it's a New York address gun in the 72,000 range with an iron trigger guard and backstrap. That wouldn't be totally out of the ordinary as following the closure of Sam Colt's London factory in 1857, leftover parts including iron guards and backstraps were shipped back to the Hartford plant and used on American production. We see iron straps on 1851 Navies and 1849 Pockets as a result but this one is different. All the iron strapped 1851's I've ever seen had the London-styled large bow style trigger guards but this one is different. Instead of the large iron bow, it has a small iron trigger guard that is the size of a brass guard you see on a 3rd model. I almost wonder if this small iron guard was something the London factory was considering but never used...only to be sent back to the States years later within the large quantities of parts and unfinished guns after they closed.
2. This Navy appears to have been originally tin plated as there are traces of it remaining on the bottom of the barrel, top of the loading lever, as well as protected areas of the hammer and frame. The trigger guard and backstrap however were originally silver plated as these show some tarnish. Very unusual to see an 1851 with a plated finish.
3. This one appears to have special sights which is not terribly uncommon...this feature you'll see from time to time. Rather than a pin front sight, it had a fancier sight that was dovetailed into the front of the barrel that resembled a miniature version of a Rocky Mountain Front. Someone has trimmed it down long ago but that appears to have been what was originally there. The rear sight is in the form of a fancier elongated V-notch on the hammer. Given that the hammers were case hardened, this fancier V notch would have been difficult to accomplish outside of the factory.
The other item this Navy Revolver has that is definitely a leftover from the London factory and often found on American production from circa 1857-58 is a nice pair of London Slim Jim grips in English walnut. They are fantastic with about 60% of the original varnish remaining.
Overall Condition grades to NRA Antique Very Good Overall with strong traces of original plating in protected areas and side of the frame. The grips grade to Fine. The barrel and cylinder are mostly a gray patina that could stand a careful cleaning if desired. The New York barrel address is sharp and legible. Cylinder is in good shape with about half of the original roll engraved scene still visible. The serial numbers are all matching. Very Good screws overall. Good mechanics. Frame, wedge, and barrel are tight with no play or wiggle. Bore is Good+ with strong lands and grooves with no rings or bulges. All in all, a very interesting Colt Navy with a unique tin plated finish, fancy sights, and some very unique Colt London DNA.