Prince William Proposes to Kate Middleton with Princess Diana’s Engagement Ring

Feast your eyes on Kate Middleton’s royal engagement ring! Now that Prince William and Kate Middleton have copped to wedding planning, she can show off her stunning engagement ring bling!

Prince William proposed with his late mother's platinum, diamond, and sapphire engagement ring. The oval-shaped blue sapphire weighs in at a whopping 18 carats, and is surrounded by 14 dazzling white diamonds. I wonder if Kate Middleton and Penelope Cruz will be comparing notes & sizing up each other's very similar engagement ring rocks?!

Here's to this royal engagement, and to one more vote for the "Color is Back" 2011 engagement ring trend!