Undoubtedly the best-known item in Kate's jewellery collection is her engagement ring. The oval blue sapphire surrounded by 14 diamonds was the ring that Lady Diana Spencer selected herself after Prince Charles proposed in 1981.
It was from a selection of rings from the former Crown jewellers Garrard of Mayfair and cost £28,500.
"It's very special to me. As Kate's very special to me now, it was right to put the two together," William said on the day of their engagement announcement. "It was my way of making sure my mother didn't miss out on today and the excitement, and the fact that we're going to spend the rest of our lives together"