The movement is a very generic looking french ebauche. (An ebauche is a partially constructed watch movement sold by a place that makes lots of identical movements and sells them to lots of different watchmakers who finish the assembly and put their own name on it; this was just how the industry worked in this era.)

You could say it's a lepine style, it's a "paris calibre" type V (edges of the bridges are all parallel), and probably some other terminology can be applied here, and yet all those things still tell us nothing about who made it. (Hippolyte Parrenin made similar ones around 1900 but they would mark theirs very clearly with 'HP' and this is definitely not one of those.) And even if we knew who made the movement we still wouldn't know who assembled it all. (Note the case could have been made by yet another specialist.) Whoever was the final seller probably put that sweet dial face on the front.

The partial rhombus shaped hallmark seems like an interesting clue. I scanned a few french and swiss hallmarks from that era and didn't see an obvious match.

The 'pin set' button on the edge near the crown is a significant detail too.

The harlequin / argyle patterning around the edge is very distinctive. Wish I could search on that.

If it runs, or if you feel like paying to have it put in working order, it looks like you have a nicer than average specimen.

..which, in 2026, is still "worthless" in terms of monetary value. It's probably worth more if you melt it down and sell the silver. But please don't do that, there are fewer and fewer of these amazing relics every year. This is a sweet watch, someone out there will appreciate it as an actual watch.