I don't think I have ever seen a ring over 15 grams, that must be a monster!
Congrats on that honker. Looks like a 2 tone ring and the hallmarks look to be european? The 750 is easy, but would be interested to know if the preceding one that isn't clear in the image is for another type of metal. Do you have another clearer picture of the hallmarks?
RainorShine it is a Platinum with 18k yellow gold