Conclusive evidence would be extremely difficult because there is no distinctive mark to indicate the country of origin.
.800 standard was very common in many European countries.
It could be a snuff box but also a pill box (more likely).
Millesimal fineness 800 was not used anywhere in Europe before second half 19th century, or even later.
Nicely hand engraved.All said I would date it late 19th or early 20th century.