The Württemberg Pearl Tiara was originally made in 1897 for Queen Wilhelmina of the Netherlands. She had become Queen at the age of ten, and the tiara was made just before her eighteenth birthday, when she was crowned.
It's an elaborate (or ornate) tiara that is quite difficult to wear successfully. It was made of 11 pear-shaped pearls, 35 round pearls and diamonds.
In 1966, the tiara was given as a gift to her granddaughter Princess Beatrix (later Queen Beatrix of the Netherlands) to wear on her wedding day.
As you can see, the tiara was huge and the pearls big. The embroidery on the skirt of Beatrix's wedding dress was designed with the same pattern as the tiara. She managed to pull off the look with aplomb.