Maria Doulton: We're all fascinated with diamonds, and in particular coloured diamonds, so when I heard that 'The Blue', a 13.22-carat, vivid blue diamond was coming to London, I came along to Christie's to find out more.
I had the chance to talk to David Warren, who is the Head of International Jewellery here, and he has great experience in coloured diamonds.
David, there is one very important diamond here called 'The Blue'; can you tell me a little bit about it?