Inside circle of ring is 1.7cm in diameter. I thought this was sterling silver but not really sure as I can't see the sterling silver marker on the actual ring only the cz for cubic zirconia and some other unidentifiable mark, maybe someone might know what the other mark means? Ring is in pretty good condition, no noticeable signs of being misshapen and only very fine almost invisible scratches from normal wear and tear. Three cubic zirconia stones.