Princess Diana picked a 12-carat Ceylon sapphire surrounded by 14 diamonds—a look later worn by Kate. Grace Kelly was first given an eternity band of rubies and diamonds, then an emerald-cut Cartier stone. Queen Máxima’s ring centers an orange oval diamond as a nod to the Netherlands.
Meghan’s custom ring includes a Botswana-sourced center diamond flanked by two stones from Prince Harry’s mother. Other notable picks: Wallis Simpson’s 19.77-carat Cartier emerald (sold for $1.98M at Sotheby’s), Princess Madeleine’s four-carat Asscher and Princess Eugenie’s padparadscha sapphire.