Thought so. Belgian. Liege proof marks and dates them around 1900
Hmmmm, the feds consider any gun manufactured on or before 1898 as an antique and exempt from federal gun laws. It would be ALOT easier to sell what looks like a late 19th century gamblers kit if guns were made before 1898. Some of these gamblers kits are very valuable, naturally, it all depends on the details, date of guns, is kit complete, condition, etc. I would have this checked by an appraiser that specializes in arms.