Wax seal ring? old? unknown hallmarks, help appreciated.

[Treetails]

Hello any information on this ring would be much appreciated, it appears to have writing on the back of the disc too but i don't think it's readable, i've shown this in the last photo.
I have no idea how old this ring is, only thing i know is it's 900 silver and i guessed maybe it could be an old wax seal ring??? Not sure on this though.
Thanks in advance.

[AG2012]

Hi,
It is a replica of medieval ring by Museum of Applied Art, Belgrade,Yugoslavia (now Serbia).
Replicas were made by the jewelry factory Zlatara Majdanpek (‚‚ZM‚‚ mark on the left).
The mark on the right is ‚‚cockerel‚‚ mark for small articles in Kingdom of Yugoslavia introduced in 1933 and continued to be used ever since.
The ring was made in late 20th century.

Regards