When it comes to engagement rings, many people think instantly of diamonds. But royals like Princess Anne, Princess Diana and Princess Eugenie have debuted some stunning sapphire rings over the years. The royal trend for these precious stones has also caught on abroad, as some European royals wear sapphire engagement rings too.

Princess Diana and Kate, Duchess of Cambridge

Perhaps the most iconic sapphire engagement ring is the one debuted by Lady Diana Spencer in 1981 upon her engagement to Prince Charles.

A real show-stopper, a central oval 12-carat sapphire is surrounded by a halo of 14 diamonds and set on white gold.

The ring now belongs to Prince William’s wife Kate, Duchess of Cambridge, who wears it in a fashionable ring stack with her Welsh gold wedding band and diamond eternity ring.

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Princess Anne

Princess Anne received a sapphire engagement ring from her first husband, Captain Mark Phillips, and another sapphire sparkler from her second husband, Vice Admiral Sir Timothy Laurence.

Clearly a fan of the blue stone, Anne’s second engagement ring features a cabochon oval sapphire flanked by diamonds.

The ring is crafted in a vintage theme and is understated, making it perfect for a royal famed for her no-frills approach to public duty.

Queen Mathilde of Belgium

Queen Mathilde of Belgium debuted a ruby ring after her engagement to King Philippe was announced, but she rarely wears it now.

Instead, she often wears a sapphire and diamond ring that she is thought to have received as a 10th wedding anniversary present.

Princess Marie of Denmark

Princess Marie of Denmark was given a ring with a ruby, diamond and sapphire from her husband-to-be, Prince Joachim.

The precious stones were arranged to reflect the French flag as Marie hails from France, and are set on a wide gold band.