Unknown mark on 925 bracelet possibly overplated in gold?

[GabbyLilith]

I'm not sure how long this bracelet has been in my family, but it is a very simply designed sterling cuff bracelet that appears to be plated in gold, or possibly patina to a yellowish hew. I can easily make out the 925 stamp, but the other stamp appears to be a torus within an oval. Hopefully the attached picture will help with both identifying the mark as well as if it is plated in gold over the sterling, or simply an old patina.