Halo tiara in platinum, with brilliant-cut and baguette-cut diamonds, with scroll or palmette motifs.
This tiara was originally comissioned from Cartier London by the Duke of York for his wife. The piece was worn by Queen Elizabeth I, who passed it down to Elizabeth II (currently the Queen of England).
The headpiece has made other appearances. Princess Margaret, the queen's sister, wore it in the 1960s. About a decade later, Princess Anne, daugher of Elizabeth II, donned the tiara. Most recently, Kate Middleton wore the piece at her wedding and to an event earlier this month.