The sparkler, thought to be late-19th or early-20th century, originally belonged to Princess Dagmar, the fourth and youngest daughter of King Frederik VIII of Denmark and Queen Louise of Sweden and Norway.
Princess Dagmar married for love, and although her husband Jørgen Castenskjold was of noble birth, their children were deemed to be commoners, denied regal titles and so had no compelling need for expensive courtly jewels.
Consequently, when Princess Dagmar died in Denmark 1961, her floral tiara reverted to the royal family.
The inheritor was her nephew King Frederik IX, who on his death in 1972 passed it along to his eldest daughter, Queen Margrethe II of Denmark, who has been photographed wearing it on at least three occasions.
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The tiara is one of "an interesting group of head ornaments owned by the Danish royal family" according to tiara expert Geoffrey C. Munn, author of Tiaras: A History of Splendour, the standard work on the subject.
French-born Princess Marie's dark hair serves as the perfect foil for the diadem's myriad clear stones, set symmetrically within congruent floral motifs to brilliantly reflect surrounding light.
Since her wedding, the princess, who celebrated her 40th birthday in February, has worn the topper to a range of occasions and events, including family celebrations, the annual Danish New Year’s Courts and to Queen Margrethe's Annual Arts and Culture Ball.