London Blue Topaz and Diamond Halo Ring Blue Topaz 3.8 ct. Diamond 0.43 ct. 18K White Gold Other Products. Yellow Sapphire and Diamond Ring Yellow Sapphire and Diamond Ring 18K Yellow Gold More Detail Diamond Drop Earrings Diamond 0.83 ct. 18K White Gold More Detail 9 Colored Gemstones Ring 18K Rose Gold More Detail Emerald and Diamond Halo Ring Emerald 0.48 ct. Round Diamond 0.73 ct. Baguette Diamond 0.75 ct. 18K White Gold More Detail