Chasing & Repousse
Chasing is a term used to describe the technique in which certain parts of a malleable metal object (usually silver) is hammered from the exterior/front in order to 'sink' the metal and create a relief/3-dimensional texture.
It is often misinterpreted with "repoussé" which is the exact opposite - a process in which a malleable metal is hammered from the interior/reverse side to create a low relief.
Both chasing and repousse may be combined to create an even further sense of depth/design.
The edges of the box is a chased design - a typical Georgian design found on snuff boxes.
Below is a snuff box with a fully repousse covered design. The design has been hammered from the interior-out/reverse side creating a different effect from chasing.