Hi Scot , that looks like a really lovely custom made contemporary ring you have there. In an effort to try and answer this one, could you upload a photo of the FRONT of the ring in a follow-up submission. Also close up photo of the mark if possible in another follow-up. Please could you type "JsC Hallmark" in the subject heading of the follow-up posts so that we can quickly assign the photos to your original question here.
Could you provide any information that might help us in focusing our research to a particular period or region? Any other information you may have already discovered and any other details that will help.