Sapphires
Kate Middleton’s stunning blue sapphire engagement ring recently caused a resurgence in the popularity of colored gemstone engagement rings. The irony in this “trend,” however, is that engagement rings with vibrantly colored gems
have been in vogue among European royal families for generations.

Often the choice of gemstone is a nod to a country’s national color or the colors of its flag, or is a family heirloom taken from other pieces of jewelry, such as a crown. For many royals, their choice of gemstone tells a story.
In the eighteenth and nineteenth centuries, the blue sapphire was the  most sought after gemstone for engagement rings, in part because their color was believed to symbolize the heavens.
 
Kate Middleton’s dazzling sapphire halo engagement ring brought the blue sapphire back into the limelight. The ring was originally selected by Princess Diana in 1981, shortly after accepting Prince Charles’ proposal.

One of the most memorable royal weddings was that of Grace Kelly to Prince Rainier III of Monaco in 1956. Engaged after knowing each other for mere days, this whirlwind romance and Hollywood-Royalty union lasted until Princess Grace’s death in 1982. Prince Rainier originally presented Grace Kelly with a Cartier eternity band of rubies and diamonds, but when he saw that big diamond
engagement rings were in fashion among Hollywood starlets, he replaced it with a 10.5-carat diamond ring.

Princess  Margaret, Countess of Snowdon, wore a ruby engagement ring custom designed by her husband. The luminous red gemstone was surrounded by diamonds and – in a heartfelt touch – shaped to resemble a rose in honor of Princess Margaret’s middle name.

Duchess Sarah Ferguson’s engagement ring did for rubies what Princess Diana’s ring did for blue sapphires. Prince Andrew, who designed the ring himself, selected a red ruby as a nod to his beloved’s fiery red hair. The mixed metal ring features an oval ruby surrounded by a sparkling halo of ten diamonds.

Emeralds
Emeralds have been prized since ancient times, when they were worn to encourage healing and to foster love and contentment. The green emerald symbolizes faithfulness and continuity and is a rare but stunning addition to an
engagement ring.