On the weekend, my sister and I spotted some "Crown Jewel pre-made craft kits" on a UK site (unfortunately, I can't find the link right now, but will add it when I do!).
Inspired this post on Red Ted's Art Blog and my old 1973 version of The Queen, we cut out the shapes from my cardboard stash (the cardboard is cereal box weight). (Not shown: two additional strips of cardboard for the top of the crown and white felt for fur for the bottom).
After painting the cardboard gold (DecoArt's Spun Gold), the kids decorated the crowns with stick-on jewels. I added white felt and painted on black spots because I didn't have any leopard faux fur in my stash.