New to Decorating and Need advice on Modeling Chocolate

do you have the equipment to airbrush and the equipment to spray cocoa butter???

some of the metallic products/dusts/foils are edible and a lot of them are not edible so there's that  too

but the learning curve and equipment needed to spray melted cocoa butter is quite a bit for just a crown

you can do a lot with cocoa butter but painting it on will not be smoothie smooth like fondant

it's a fat and it needs temperature control to perform like that

but it would stick fine

but i'd recommend you using fondant or gum paste

While gumpaste is technically edible, you probably wouldn't like it and if it's used for decorations, it will be too hard to eat anyway.  Modeling chocolate tastes great and is good for covering cakes, but if you're going to make decorations that need to hold their shape (like a crown) you'll want to mix it about 50/50 with fondant or gumpaste.

I would suggest making the crown with fondant or a modeling chocolate/fondant mix. You can find several really pretty templates here on CC.  After it dries and holds it shape well, paint it with luster dust mixed with a clear alcohol like vodka or rum. All you need is a paintbrush.

I recently read on a chocolate making forum that you can spray cocoa butter through an airbrush, but you have to heat the airbrush up, too. They used a heat gun, but said a blow drier would work too, but take longer. I also wonder if anyone burned their hand trying it! I used a heat gun to soften vinyl tile to cut it on the diagonal, for the floor of my bakery, and I accidently touched my ankle to the tip if it, and my skin sizzled and bubbled immediately!