In a previous post I wrote about history’s most iconic wedding gowns including those of Grace Kelly, Elizabeth Taylor and, most recently, Kate Middleton. Even more than her Sarah Burton-designed dress, I adore the diamond-encrusted sapphire engagement ring Kate wears, which Prince Charles originally gave to Diana, and which her son William presented to his new financee when he proposed in 2010.

I’m old enough to remember when Diana first showed off her engagement ring back in 1981 and I feel oddly sentimental every time I see it on the new princess’s finger.

Although grand, the ring was not custom made but chosen by Diana from the Crown jeweller’s collection, yet another example of Diana’s departure from the “royal” way of doing things. (Previous betrothed members of the royal family would opt for a one-of-a-kind engagement ring.) Diana also chose to marry Charles at St. Paul’s Cathedral rather than the traditional royal wedding venue, Westminster Abbey. She then left out the word “obey” when saying her vows at the altar which caused quite a ruckus at the time.

Diana continued on a somewhat unorthodox path by becoming involved in causes normally outside the job description of a royal princess, embracing the true meaning of Christian charity. The day after her divorce she resigned from over 100 charities so she could dedicate her time to just six, including the Leprosy Mission and National AIDS trust.