
It's hard to tell with Queen Juliana but in
this picture, it almost looks like she's wearing
Queen Wilhelmina's Diamond Haircomb. Then again, I believe there are other diamond haircombs and small tiaras in the Dutch collection (mostly, coming from Wilhelmina as well), so it's hard to tell. She's wearing the devant de corsage from the Melleiro Ruby Parure and her necklace appears to be a combination of rubies and diamonds, so it's a safe bet to say that the hairpiece is either all-diamond, or ruby and diamond as well.
Juliana and Beatrix were Queens Regnant and focal point of the ceremony anyway. Maxima is the first Queen Consort in nearly 123 years so there is no fixed tradition what she can or cannot wear. The Dutch Inauguration ceremony is probably closest to a coronation among the continental ceremonies so I'm hoping for something that will
scream "Queen". Or, in other words, I'm hoping for the Stuart.