Vanity jar lid question

[Adam.NYC]

I have had many of these and all of them were marked. I can't find marks on this other than the numbers 45 and 37 which I imagine are the style numbers. I am positive this is sterling but I could be wrong. I know it should be marked if it is sterling. Can this be plated? The quality seems too good to be silver plate. Thanks!

[asheland]

Nice piece! Given the overall appearance and that terrific monogram, I'd be surprised if it wasn't sterling...
I bet there's a sterling mark hiding somewhere on that piece.

[Adam.NYC]

Thank you! That's what I thought, too. I will keep looking with my loupe!