The Royal Watcher has a page on the wedding with photos of the leading guests.
See http://royalwatcherblog.com/2019/09/08/wedding-prince-knud-princess-caroline-mathilde/
From what little I know most of the jewels are still in existence.
Which ones are you interested in?
Which tiara are you referring to when you say "even the tiara Queen Margarethe II wore on that Day"? Did you mean Queen Alexandrine?
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