Size 7.5, but it can be resized. The old European cut diamond weighs in at approx 5.0 mm (estimated 0.45 carats). Small chips to the diamond due to surface inclusions but nothing that can be seen without a loupe. Some natural inclusions visible under magnification and one small black inclusion is visible to the naked eye. Sexy big culet at center. Rosy 18k gold. Weighs 6.27 g. Nearly invisible evidence of a previous resizing. Owl hallmark. c. 1900.