Town & Country reports, and exactly what it says is a closely guarded secret. According to royal biographer Ingrid Seward, in new book Prince Philip: Revealed, "No one knows what it says, other than the engraver, the Queen and her husband." What's more, the monarch "never takes it off," Seward writes—so there's no chance of any fellow palace dweller sneaking into her room while she sleeps and snatching the ring from her nightstand to solve the mystery.
Seward writes that Prince Philip, in keeping with royal tradition, had the ring made from Welsh gold, after "the people of Wales supplied a nugget" of the rare metal.
A post shared by The Royal Family (@theroyalfamily)The royals upheld the tradition for 21st century royal brides Meghan Markle.
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