Since the wedding of the Duke and Duchess of Cambridge Sapphire sales have rocketed, due to Kate Middleton receiving Princess Diana’s classic Sapphire and Diamond engagement ring. Like his grandfather, Prince William gave Kate Middleton Diamonds that belonged to his mother. The diamonds for Queen Elizabeth II's engagement ring from Prince Philip also have a special history. The diamonds came from a tiara belonging to his mother – Princess Andrew of Greece. Prince Philip was involved in the design of the queen’s engagement ring. The engagement ring is a platinum ring set with eleven diamonds, a 3 carat round solitaire and five smaller stones set on each shoulder. Queen Elizabeth II met Prince Philip when they attended the wedding of Philip's cousin, Princess Marina of Greece to The Duke of Kent. Their engagement was announced on the 9 July 1947. Prince Phillip proposed to Queen Elizabeth during a walk around the grounds of Balmoral. Their wedding took place the same year at Westminster Abbey.