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Yes, the oval mark is Latvia's control mark for silver. However, the circular mark is not an actual hallmark but a warrant mark used in Latvia 1927-1940. It was punched on silver objects with attached parts as an indication of assay.
Forgot to tell that the oval shaped hallmark was implemented 1994. I believe that it is a remarking done after 1994. The original hallmark is the 875-mark from 1922-1940.