Russian napkin ring?

Hi everyone,
First post by a newbie so hope someone can help. I picked this up the other day (and bought it, obviously!) - an enamel serviette ring which I hope is Russian silver, although if it is I can’t find the town mark on the online silver sites. There is also a stamped name which looks like ‘Adler’ but I’d have thought it would be in cyrillic. Any ideas would be much appreciated.