Diamond experts at Taylor and Hart estimated that the ring would cost around £200,000 to create today.
However, its association with the late monarch and its historical provenance would “make the ring priceless”, they said.
Taylor and Hart’s design director Kate Earlam-Charnley commented: “The centre diamond is a 3.0ct Old European cut which originated from a diamond tiara which belonged to Prince Philip’s mother, Princess Alice.
“It’s a timely design that carries all the noblesse of Queen Elizabeth. Featuring eight eagle prongs, we’ve created our own interpretation of the majestic engagement ring.
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