This is not a royal tiara, but one that was recently created by Los Angeles designer Irene Neuwirth for singer-songwriter Joanna Newsom when she married comedian-actor Andy Samberg. I thought some of you might be interested since there was a thread recently about different kinds of opals.
Although not royal or classical, I really like this for its unique mixture of stones and the asymmetry. I can totally see one of the Danish royal ladies (daisies!) wearing something like this.
[The pictures are from the designer's Facebook page.]