Well, there are a lot of exquisite jewellery among the different Royal Families in Europe (as well as in other parts of the world), and I love to see all the tiaras, necklaces, earrings, and so on, being worn at different events, on TV, and on photos, rather than being in museums, just to be seen by visitors, and at risk to be stolen, and then most likely broken up by the thieves.
Much of the royal jewellery have historical value, with connections to earlier generations, and countries through marriages, and so on. The Swedish Royal Family have jewellery connecting them with France, and Napoleon Bonaparte's time, and some of those items are now in the Danish, and Norwegian, Royal Families, given as wedding gifts, or as inheritance, showing the connections between the Scandinavian Royal Families.
The Scandinavian Royal Families have more 'tiara events' than the British Royal Family, as most royal weddings, and other aniversary celebrations, and such, are usually 'white tie dress code', and the other European Royal Families are usually invited. From the British Royal Family, the guests attending has been Edward and Sophie (Wessex/Edinburghs).
OT: Historically Sweden and Denmark have fought the highest number of wars, and armed conflicts, between two nations (at least 13, up to 30 or more), from the late 15th century to 1814. There have been several royal marriages between members of the two Royal Families through the centuries, four of them after 1814.