toi et moi–style engagement ring, which appears to have similarly sized cushion- and round-cut diamonds in lieu of a single center stone—plus tapered baguettes on the band.Rainier III of Monaco initially proposed to American actress Grace Kelly in 1955 with a Cartier band of rubies and diamonds.
Soon after the proposal, he upgraded to a platinum Cartier engagement ring with a 10.47-carat emerald-cut diamond flanked by four diamond baguettes.When Prince Philip Mountbatten of Greece and Denmark was set to propose to the then Princess Elizabeth in 1947, he picked a three-carat round center stone, and surrounded it with 10 smaller diamonds from a tiara owned by his mother, Princess Alice.
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