Russian Hallmarks but what do they mean?

[Christina21]

[AG2012]

Hi,
It was made in Tallinn, Estonia, after 1958. At the time, it was Soviet Republic of Estonia.
Star, sickle and hammer, fineness 916 and assay office code 3 for Tallinn.
Regards

[Christina21]

Thank you for your help!
I find these rings so interesting with the more unusual hallmarks (unusual for the UK anyway!)