925 Sterling Silver London Blue Topaz & White Topaz Ring Size 6 3/4. Beautiful ring featuring 3 marquise-cut London Blue Topaz, approximately 0.87 ctw, and 2 white Topaz, approximately 0.14 ctw, totaling just over 1 carat of beautiful topaz in this ring. The stones are set in 925 sterling silver and each stone has a crown-like grouping of prongs around them. Unique and secure! It is a size 6 3/4 and weighs 2.94 grams. In great used condition! Minimal scratches on the band. Otherwise, looks almost brand new!