Thanks for responding @Canturi loverHi BeenBurned, it’s a beautiful ring! Great find. Does it have any other marks? How much does it weigh? The number 58 could be the size so check the diameter- it will measure around 18.5mm if it is the size marking. Appraisals can be expensive, especially if your really not sure that the piece is worth it. You could always take it in to a local pawn shop as if you wanted to sell it. They can do the acid test there and then to tell you what metal it is. Finally, if it is real and you want to size it, it will most likely cost quite a bit as it looks like the setting is a full band. Hope this helps [emoji253]
Would 18.5 mm be the inside diameter or outside. OD is about 20 mm and ID is about 18 (or maybe 18.5. (It's difficult to measure.)
I don't have a jewelry scale to weigh it but the quality seems better than costume jewelry and that's why I took the chance on it.
I will take it (at some point) to a pawn shop or jeweler for testing.