From her sapphire and diamond engagement ring to her yellow gold Cartier Tank Française, some of the late princess's most beloved pieces have ended up with her daughters-in-law, while others haven't been seen since Diana's death. Princess Diana loved jewelry, wearing her favorite pieces over and over, even as every ring, bracelet, and earring was photographed, scrutinized and analyzed. Since her tragic death at age 36 in 1997, the almost mythical lure of her jewels has only grown.