The ring is a huge piece, a massive rectangular cut aquamarine stone flnaked with diamonds.
Diana is thought to have commissioned the piece for herself, inspired by a favourite aquamarine and diamond ring.
A big fan of blue stones in general, the aquamarine was a lighter, fresher look than Diana’s deep blue engagement ring.
The piece, as a part of Diana’s private collection, was left to her sons on her death to give to their future partners, went unworn for decades.
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