Jura regalia is a fancy phrase for things that a king or queen owns and uses to show that they're in charge. You know how you might have a toy that's really special just to you, and you don't let anyone else play with it? That's kind of like jura regalia for a king or queen, but way fancier.
Some examples of jura regalia include crowns (the big fancy hats that kings and queens wear, usually with lots of jewels on them), scepters (long sticks with a fancy decoration on the end that the king or queen can hold), and even thrones (really big, fancy chairs that only the king or queen gets to sit in).
These things are important because they help show that the king or queen is in charge, and they can be used for important ceremonies or events, like coronations or official visits from other leaders. So, just like how you might show off your special toy to your friends, a king or queen can show off their jura regalia to other people to show how important and powerful they are.