This brings up a good point.
Most people would not accept an 18th Century firearm finished in an 18th Century manner.
It would either look too new....
too unfinished
too modern looking on finer guns...
too rough on American and lower grade English/Continental Guns.
You hear the phrase....workman like manner. The lower grade (trade) guns and a lot of American work is a little rough for modern uneducated tastes.
With that said, it was good work and far far superior to say North African or Balkan...Ottoman type work.
Sometimes builders go too far with the grunge look producing a gun that looks North African.
On the other hand....Some makers produce high grade English Or Continental quality on guns that originally were not finished so fine.
Of course the Chief grade guns would be of much higher quality.
There is an expectation for a new gun to still have that 250 year old look. So a bright barrel, polished furniture and a fresh stock.....Don't look like...."the real thing".
Now on the finer guns with carving...fine furniture...blued barrels and beautiful stocks....
Hey....that looks too modern, although a gun could be finished as authentic as research and evidence allows.