Thank you Oliver! I must confess that I was totally ignorant of this movement in Ottoman art.
A current thread about
stories accompanying items from dealers brought to mind that when I bought this, decades ago, I was told the marks were Bavarian import marks. Sure enough, following several internet searches I find the larger of the two marks is a variation on the Munich coat of arms (better with a jeweler's loupe than any photo I can capture) and would be used with another mark for origin on an imported silver item before 1886. Probably an interesting story there, definitely now lost.