Help with unknown hallmarks

Can Someone please help with these hallmarks, they are on the back of a spoon that looks quite old, soon I Will add photos of it.
thanks

Hi Ricardo and welcome to this forum. Perhaps you will be able to help if we have any marks from Portugal.

Your spoon has Dutch hallmarks. The first mark is the maker’s mark, then the symbol for .833 standard silver, then the duty mark (head of Minerva), and finally the date mark. Unfortunately “O” as a date letter is a bit difficult to determine - you will find a table of Dutch date codes here. Perhaps you can match it!

Phil

Thanks a lot for your help, I will check that out.
I will definetly help if I see portuguese silver arround here.