Art Deco Platinum Hallmark/Trademark?

[decogirl]

Hi everyone!

I just bought a beautiful art deco jade platinum diamond ring, and I'm doing some research on the mark inside the shank. If anyone knows what it might be, I would appreciate it

 

[decogirl]

And here is a front view of the ring. It has transitional rounds and emerald cuts.

 

[Kismet]

It's a lovely ring!

If the piece is American it could possibly be the mark for M. Adels & Co. as shown here. I don't know anything about them (and nothing came from a quick online search.)