Chinese pill box? snuff box? Signed.

Found this at an estate sale yesterday. What would you call this piece? A pill or snuff box? Also would this green oxidation be consistent with silver? Might the white residue on the edges be silver polish?

I google imaged the signature and got this:

The image shows two Chinese silver hallmark stamps reading 吉順 (Ji Shun, likely a silversmith or shop name) and 足紋 (Zu Wen, meaning "full/pure silver" or fine silver standard).

It's fairly light in weigh, the metal seems stamped. All thoughts appreciated.