Item Type: Ring Material: Metal Decoration: Opal Stone Features: Unique Ring, Black Ring, Ring with Opal Size Info: Size Perimeter (mm) Diameter (mm) 5.5 51 16.10 6 52 16.51 6.5 53 16.92 7 55 17.35 7.25 55.5 17.50 8 56 17.75 9 57 18.19 10 58 18.53 11 59 18.89 12 60 19.41