The pearl and diamond accessory is called the Lotus Flower tiara, and it happens to be a favorite of Queen Elizabeth. It's only the third time Middleton has ever chosen to wore a tiara, according to Vanity Fair, because as we all know, the "people's princess" likes to keep her royalty on chill. Middleton first wore the tiara during her 2011 wedding to Prince William, and then again in December 2013.
Middleton's color choice for her dress was also very important, according to Elizabeth Emanuel (via People), who co-designed her gown, because "red is very important as a statement in itself as it matches the color of the Chinese flag and it means good fortune."
The banquet appeared to go off without a hitch, and Middleton looked completely on point for the diplomatic dinner.