Authentic 18K White Gold Hidalgo Enamel Diamond Sapphire Ring Band. 18K white gold blue enamel ring with diamonds and sapphire. This authentic ring is by an award winning jewelry designer Hidalgo. The band features a genuine sapphire measuring 6 mm long by 4 mm wide, surrounded by 12 brilliant round diamonds. The band measures more than 3/8 of an inch wide. It weighs 6.3 grams.