Rings was made only during first Latvian Republic (1918-1940). Like Latvian regimental badges. In period of 1940-1994 was Soviet hallmarks. In period of 1922-1940 was Latvian silver hallmarks with "Milda".
Smart things from wikipedia are good, but real life was/is different.
Up to 1930ies authorities was not tight so in use unofficially was even 84 hallmark.
In a first year of russian occupation 1940 - 1941 they had a lot things to care other than hallmarks.
During German occupation authorities didn't care at all about hallmarks, so there were unmarked things, marked with Milda 875 or even 84. Depending on who had what stamps left or made.
After war sure on officially sold items were soviet hallmarks.
At the beggining of 1990ies when russian army moved out and new Latvian government again didn't care much about hallmarking. So here was total mess around and many items were sold without hallmarks at all. However people wanted some hallmark on jewelry they purchased so in use was everything somebody had. Meaningless 925, old prewar Milda or any other ******** stamps. This is the case with ring on your page you claim to be "original". That is ring made in old die in 90ies and hallmarked 925 in order to have at least something stamped.
In the middle of 1990ies authorities become pretty tight so on officially sold items had to be official hallmark, jewelers personal stamp.
