Ring with cabochon-cut turquoise

Ring with cabochon-cut turquoise and brilliant- and old-european-cut diamonds totalling ca. 1.65 ct, central old-european-cut diamond ca. 0.65 ct, STW (I)/ SI and brilliant-cut diamonds totalling ca. 1.0 ct, of good colour and medium to good clarity, platinum, 22.5 g, ring size 56, 20th/21st century, good condition. 1 diamond missing.