Prince William proposed to Kate with Diana’s famous sapphire ring in 2010, choosing the heirloom for its personal significance rather than as a new commission; its estimated value mirrors Diana’s at roughly $520,000.
Harry commissioned a bespoke ring with a cushion-cut diamond from Botswana flanked by two stones from his mother’s collection. The band was later altered from yellow gold to a micro-pavé style; estimates place it near $300,000–$350,000.
Camilla received a family heirloom: a 5-carat emerald-cut diamond once owned by the Queen Mother, framed by baguette side stones in an Art Deco arrangement, valued at about $288,000.
Philip designed Elizabeth’s engagement ring with 11 diamonds, including a central 3-carat stone and ten pavé diamonds taken from his mother’s tiara and set in platinum. Once modestly priced, its modern estimate is near $250,000.