Kate Middleton stunned at a Windsor Castle state banquet for German President Frank-Walter Steinmeier, debuting the Oriental Circlet Tiara, her largest and first worn to date, paired with a sequinned blue Jenny Packham gown. Earlier at Heathrow, she welcomed the guests in a blue Alexander McQueen coat, Burberry dress, Diana's sapphire earrings and the Prince of Wales feather brooch.