Queen Nazli ordered the diamond parure from Van Cleef & Arpels in preparation for her eldest daughter, Princess Fawzia's, marriage to the Shah of Iran in 1939. It was previouly auctioned along with some of her other jewellery at Sotheby's in 1975, a few years before her death.
She seemed to have an extraordinary collection of jewellery. I've seen pics of her wearing at least two other tiaras and a few different pairs of large diamond earrings.