Maxwell Stone from Steven Stone jewellers estimated just how much the fabulous, elegant piece is worth.
He stated: “Only a very small percentage of pearls used for jewellery are natural, with most of them being cultured.
“If these pieces are made up from natural pearls, they are going to be incredibly rare, not to mention valuable.
“One single natural pearl is worth around £3,000, and as the Queen has a three-strand necklace, this could be worth anywhere from £600,000 to £1,000,000.”
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