There are 4 different types of materials I would recommend making your tiara with:
1) Gum paste/ Pastillage
2) Royal Icing
3) Chocolate **Recommend using the Wilton Candy wafers as high quality chocolate will be thinner, and more difficult to pipe for this format. Plus you need a nice & thick chocolate for stability!
4) Sugar dough
Additional Materials needed:
Fine paint brush **only used for edible materials!
Edible pearls/ dragees
Pearl luster dust/powder (In gold, silver, or color of choice)
drawn out tiara design (template)
silicone fondant/ gum paste molds
tips/ pastry bag
medium sized can or container
In addition, I would stick with ENTIRELY edible materials! (Even if you don't think anyone will try to eat this, you never know, and I would strongly advise against using the plastic gemstones you purchase at craft stores- for a more "bling" look! Not a good idea!) There are so many great products now that could be used for finishing, such as the pearl luster powders, and the amazing colored "glitters", and dragees. Also, in some specialty cake supply stores, you may be able to find edible gold leaf as well!
If you are a skilled sugar artisan, and have worked a lot with Royal Icing, (Australian Lace work, etc.), in combination with the gum paste or pastillage would be my number one choice, as it is the most intricate and realistic looking version!
If you haven't worked much with royal icing, I would recommend using strictly a dough or paste- such as sugar dough or the gum paste/ pastillage only. I don't recommend using fondant at all! (It will not dry as solid or hard as the gum paste or pastillage. Chocolate can actually be very tricky too, as the consistency is key, along with the difficulty of piping on a curved surface. (Yes, it was even tricky for me!)
Questions before getting started:
How big is the cake that this will go on? (Or how large does centerpiece need to be?)
What is the size/ circumference & height of tiara ? Design? (Intricate or simple?)
Once you have the answers to the above questions, it's time to begin!
1) Design or photocopy your tiara design according to the appropriate size you need.
2) Find a can or plastic container to act as the "mold" for setting your tiara.
3) ** If using sugar dough and baking to set hard, you will need a tin can with paper removed, to bake the main design on. Use the copied paper or cardboard template for cutting out the dough.
(Once dough is baked, the form will remain on the can until decoration is complete.)
**If using gum paste, royal icing, or chocolate, then tape the drawn design down first- along the base of the can or container. Then, tape down a strip of parchment to entirely cover the design.
4) Next, begin to roll, cut, or mold the strips of gum paste if you are using. I "glued" my pieces together with a bit of egg white. You can use ALL gum paste, or combine with royal icing. Royal icing must be thick! (You also want the structure strong, so pipe a second layer of royal icing over the first. Make sure to allow 2-3 days of proper drying in a moisture free/ dry environment at room temp.
**If you are using chocolate, make sure it is tempered, and pipe the outlines, then fill in. Depending on thickness or consistency of chocolate, you may want to do a second layer piped over first as well- to strengthen. Before the royal icing or chocolate sets, place the pearls or dragees where you want them to go. **Allow to dry overnight.
5) To finish, simply take a clean and dry paint brush, (used for edible decorating only!!), and brush over the chocolate, gum paste, or royal icing with the luster dust to add a finished look!
6) Very carefully remove from the can/ container- making sure to handle from the base and not the top!! Place on top of cake or centerpiece. If transporting for placement at location, find a shallow and round container, and place a foam like substance that will cushion the tiara, and protect it from any shifting.
***If breakage occurs, make sure to have tools for quick fix, or a backup tiara! (Believe me, I broke mine while placing on the cake in the above pics, and had to use my 2nd choice backup tiara!)
Good luck, and I hope you have fun creating your edible tiara!!