02 LA PEREGRINA NECKLACE BY CARTIER, 1972

SOLD: $11,842,500 (£8.7m)

This ornate piece features La Peregrina, a pear-shaped pearl found some 500 years ago and once owned by Queen Mary I. After Richard Burton bought the pearl as a gift for Elizabeth Taylor, the actress had it made into a necklace. It formed part of Christie’s New York’s 2011 sale, The Collection of Elizabeth Taylor, which realised over $156m (£100m) and generated more than 57,000 bids. The necklace is the most expensive pearl jewellery ever sold at auction.