It could be this was eventually happened : the same misadventure happened to Queen Ingrid during the 100 th anniversary Greek dinasty celebration.
But let us recognize that GD Josephine Charlotte didn't have a great emerald tiara to wear in a such great event. The VCA necklace as tiara is lovely but rather simple for a royal wedding.
Of course a tiara loaned is the most surprising knowing the Luxembourg vault and her personnal jewellery. Just my guesses.
--Previous Message-- : If it was a loan....I have a question about : the circumstances. : : Suppose she went with an tiara to Denmark : but suddenly the frame broke and couldn't be : fixed or wear it any more. : : 1. Why didn't she wore her necklace as : tiara? : 2. Wich royal/aristocrat person would have : those days an extra tiara? : : :