That is the most unusual ring I have seen.  How strange that Tiffany couldn´t tell you more, surely something like that wouldn´t be too difficult for them.
I wonder if you got someone unhelpful....  It looks like art deco, try OMC he should know more about it than I do.
I like it.......

Joia

You need to make a little visit to an Antiques Roadshow.  They can always get to the bottom of things.   That being said....that is really cool.   Perfect for one of those fat days. 

GG-thanks   That is what I mentioned to joia---a very 'practical' ring 

OMC-the only info I have is from the previous owner's daughter, she is 78 and remembers her mom receiving it when she was young---so thinking 65 to 70yrs old(she wasn't sure of her age exactly!?!?!).  And a 20+yr old appraisal, with out any age info.  So OMC, you'd be right on

The only other marking(other that makers mark and gold hallmark) is the number '471' on the inside of one of the links. 

OMC-to answer your question, I had emailed info and pics to T's on 5th awhile back---and was told that they have their pieces made in so many places that they are really unable to date a piece from markings, because they were all different.  Seemed like a bunch of bunk and I Thought that the man was maybe just unwilling to help actually!!!