Fergie also donned the pricey headgear to Elton John’s 2001 white tie event.
Maxwell Stone, the creative director at Steven Stone, told Express.co.uk: “The stunning diamond tiara, with a huge five-carat centre stone, is surrounded by an intricate swirled pattern of diamonds of various sizes.
“It’s a remarkable piece, however, with a value of around £250,000, it’s not quite as expensive as some of the other royal tiaras we’ve seen.
“The Greville Emerald Kokoshnik tiara worn by Princess Eugenie on her wedding day is the most valuable tiara overall, worth an estimated £10million.
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