Diamond experts at Taylor and Hart estimated that the ring would cost around ÂŁ200,000 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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