This mark came from some sort of strange cup... maybe a shotglass? It has M/S Oslofjord engraved on it, which is what clued me in to its Swedish or Norwegian heritage.
Any clues as to who, what, or when?
Also, HUGE props to you guys - I have been listing a TON of silver on eBay and have used information I found on 925-1000 and in these forums to help me identify MANY pieces. I finally decided to just create an account, so this is my first post.