My inspiration — ring made of red gold with a diamond

Ring sizes: A (Diameter: 11.95 mm) A 1/2 (Diameter: 12.18 mm) B (Diameter: 12.37 mm) B 1/2 (Diameter: 12.6 mm) C (Diameter: 12.78 mm) C 1/2 (Diameter: 13 mm) D (Diameter: 13.21 mm) D 1/2 (Diameter: 13.41 mm) E (Diameter: 13.61 mm) E 1/2 (Diameter: 13.83 mm) F (Diameter: 14.05 mm) F 1/2 (Diameter: 14.15 mm) G (Diameter: 14.36 mm) G 1/2 (Diameter: 14.56 mm) H (Diameter: 14.65 mm) H 1/2 (Diameter: 14.86 mm) I (Diameter: 15.04 mm) I 1/2 (Diameter: 15.27 mm) J (Diameter: 15.4 mm) J 1/2 (Diameter: 15.7 mm) K (Diameter: 15.8 mm) K 1/2 (Diameter: 16 mm) L (Diameter: 16.1 mm) L 1/2 (Diameter: 16.41 mm) M (Diameter: 16.51 mm) M 1/2 (Diameter: 16.71 mm) N (Diameter: 16.92 mm) N 1/2 (Diameter: 17.13 mm) O (Diameter: 17.35 mm) O 1/2 (Diameter: 17.45 mm) P (Diameter: 17.75 mm) P 1/2 (Diameter: 17.97 mm) Q (Diameter: 18.19 mm) Q 1/2 (Diameter: 18.35 mm) R (Diameter: 18.61 mm) R 1/2 (Diameter: 18.8 mm) S (Diameter: 19.1 mm) S 1/2 (Diameter: 19.31 mm) T (Diameter: 19.51 mm) T 1/2 (Diameter: 19.84 mm) U (Diameter: 20.02 mm) U 1/2 (Diameter: 20.2 mm) V (Diameter: 20.32 mm) V 1/2 (Diameter: 20.68 mm) W (Diameter: 20.76 mm) W 1/2 (Diameter: 20.94 mm) X (Diameter: 21.18 mm) X 1/2 (Diameter: 21.3 mm) Y (Diameter: 21.49 mm) Y 1/2 (Diameter: 21.69 mm) Z (Diameter: 21.89 mm) Z 1/2 (Diameter: 22.1 mm)