story identification - Searching for the title of a Fantasy book series from the 1980's

I am trying to remember the name of a Fantasy series from the 1980's. It contained at least 7 novels.

I remember it was about a magic bottle that was entered by use of the ring. Each novel, whilst a separate story, was connected to the others, building the story of the bottle from different perspectives.

Went to re-read them but found they had been "tidied away" during a house move.

Any ideas on either title of the series or one of the books?