Whatever the truth about this amazing ruby, it must be (still is?) one heck of a precious stone. It belonged to a French king, and leapt from his ring to attach itself to the tomb of Thomas Becket, who was born 900 years ago today, in Canterbury. The ruby then ended up belonging to Henry VIII (who had it removed from the tomb and put in a thumb ring for himself). George IV then had Henry’s tomb opened up, in the belief the ruby would be inside, but it wasn’t. So where did it go?