But what is the wider significance of the ring, and what is it worth today? Express.co.uk spoke exclusively to an expert at We Love Diamonds about the late Princess Diana’s beautiful sapphire stone.
The “simple sapphire and diamond ring” can be described as “an iconic and truly beautiful engagement ring”, worth around £40,000 in 1981 when it was purchased.
According to the experts, the stunning ring would now be “absolutely priceless” – “not that it would ever be placed on the open market”.
The experts at We Love Diamonds value the sapphire ring at an astonishing amount, in excess of £12.5million.
The ring may be gorgeous in and of itself, but it apparently has a deeper symbolism attached to it.
“Ironically, while such a ring is typically intended to signify wealth, its latent natural meaning was ironically intended to represent a disdain towards infidelity.
“Read into the future connotations of that as you will but, in royal circles sapphires have traditionally been highly venerated for that reason and they are, undoubtedly, one of the blue-bloods, go-to gemstones.”
The experts pointed out that Princess Eugenie “sports a magnificent sapphire ring”, as does the Princess Royal.
Princess Eugenie’s engagement ring is a phenomenal Padparadscha sapphire, with an ethereal pinkish-orange hue.
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Princess Anne’s engagement ring boasts a cabochon sapphire framed by clusters of diamonds.
The experts noted that Princess Diana and Kate Middleton both wore outfits that complemented their rings in their official engagement photos.
“Always the forward-thinking fashionista, Diana cleverly showcased this ring to the world by wearing a matching sapphire blue skirt.
“Symmetrically (and perhaps symbolically), Catherine herself later wore a royal blue dress that mirrored William’s mother’s ring when she was confirming their own engagement to the international press.”
Diana’s engagement ring ended up on Kate’s finger in a sweet gesture of brotherly love.
Following the Princess’ death, it was actually Prince Harry who inherited her engagement ring and “touchingly” offered it to William ahead of his engagement to Kate.
“We Love Diamonds regards this as the most noteworthy of noteworthy gestures as it was clearly an overt display of the very tight bond between the two brothers, at least at the time.
“Regardless, it is emphatically known that, in memory of his beloved mother, Harry always wanted to see that ring sat on the throne in one way, shape or form.”