Well the marks all mean something. Grade, Date, Region it was made and maker. The only thing I can find is another Wedgewood ring kindof like it, but they don't offer any info or even a picture of the marks. They mentioned only that it has a lot of hallmarks. https://www.etsy.com/listing/224518..._query=wedgwood cameo ring&ref=sr_gallery-1-7 ... Maybe there's a Wedgewood collector site out there that could shed some light on it?
Ring looks like a wedding band that has had the Jasperware disc attached to it. It's unusual that the back is enclosed. You will find the vast majority of Wedgwood jewelry has an open back in order to see the marks on the porcelain itself. Cuff links are often enclosed.