Francotte.
Records go back to 1902 and Model 18 from what the seller shared with me (though it didn’t say who they were from so I can’t verify their authenticity).
The gun is more highly engraved with scrolling than most model 14s but is a basic boxlock no side plates. Which I would think would be consistent with it being an 18.
There’s a weird silvery speckling to the barrels when you look at it in decent light, but it’s silver speckling not brownish or anything. I can’t discern any actual pattern at this point
I might try that with the vinegar under the forend or something.
Also the barrel flats are oddly matte looking, and under the forend too, the “texture” of the finish is just more matte/like the re-went-over it with something or other. Not sure how to explain but it struck me as odd.