Lady Diana Spencer (later to become Princess of Wales) reveals her sapphire and diamond engagement ring while she and Prince Charles, Prince of Wales pose for photographs in the grounds of Buckingham Palace following the announcement of their engagement  (Photo by Tim Graham Photo Library via Getty Images)
The Controversial History Behind Princess Diana's Engagement Ring
Lifestyle - News
The late Princess Diana’s engagement ring is one of the most coveted baubles in the world, estimated to cost $440,000 at the time and consists of a 12-carat oval sapphire encircled by diamonds. Whatever the cut, color, clarity and carat may be, Diana's ring was controversial from the moment she picked the ring.
According to Brides magazine, Princess Diana chose the ring from a standard catalog, meaning that anyone could have chosen or copied it, which didn't impress Diana's future in-laws. Princess Diana likely chose the ring for sentimental reasons, as her mother had a similar ring, and it was reported a brooch worn by Queen Victoria inspired the design.
Princess Diana and then-Prince Charles separated in 1992, but she still wore her engagement ring and wedding band as a gesture of respect for her sons, Prince William and Prince Harry. While this ring was special to Princess Diana, it now has a new home on the hand of her daughter-in-law, the new Princess of Wales, Kate Middleton.