World’s Most Expensive Diamond Engagement Rings Facebook Prev Article Next Article 7. Grace Kelly’s Engagement Ring: The Cartier diamond comes with 10.47 carats. It also features two diamond baguettes on its sides. Prince III of Monaco presented the engagement to his wife Grace Kelly. The ring is worth $4.06 million. Previous 1 2 3 4 5 6 7 8 9 10Next Prev Article Next Article Related Posts Gloria Estefan Mansion Listed for $40 million Top 10 Most Expensive Watches Over $1 Million Should We Be Drinking Milk – Depends on What Type A Brilliant Way To Pay Down Your Credit Card Balances 15 Most Luxurious Honeymoon Destinations 15 Yummy Healthy Breakfast Under 400 Calories