Im not convinced it was a mistake. Beatrix never wore the House Diamonds or the Stuart Tiara. She was prone to migraine attacks and heavy tiara's were not to her liking. So in order to honour her hostess' request she wore the other tiara in her possession with pale blue stones. Margrethe no doubt understood and possibly even had a laugh with Beatrix about this solution.
Okay, thanks, but my question is still how Margrethe’s request became known to the public. What is your source?
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