“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.”
According to David Douglas Diamonds and Jewellery, the Queen loved her pearl necklace so much that she actually had a few backups and could rotate them freely.
READ MORE: Kate and Princess Charlotte ‘bond’ through matching outfits – pictures