5.30 Carat Oval Sapphire & Trilliant Cut Diamond Engagement Ring5. 30 Carat Oval Sapphire Trilliant Cut Diamond Engagement Ring. This modern ring features an absolutely dreamy oval cut 5. 30 sapphire with . 92 carats of trilliant cut diamond accents and finished in platinum. The beauty of using a trilliant cut diamond on each shoulder is the outer contours lead straight into the edges of the primary stone. The setting is strong and elegant and will exude that style for years to come!