Check out Fibreglast

www.fibreglast.com

Check out their online "brochure" about using glitterflake. Their first choice is to use a female mold with first a thin layer of clear gel coat. That is followed by a layer of gel coat with your flakes in it, then you put on a layer of gel coat or casting resin with a tint in it. This coat can have some glass reinforcement. Then you can add more glass and resin to make the thing as thick and/or strong as you want.

When you pop this out of the mold you'll find the glitter layer sandwiched between a background color and a clear overcoat. This multilayer rocess is qhat makes the glitter appear to float and sparkle. If it were mixed in with the colored resin it would be partially obscured.

If you want good detail in your mask use regular plaster of Paris. Most hardware stores carry it. Don't get patching plaster or spackle, which take longer to set up.

Seriously, ( and I know this sounds strange, but it has worked for me) get some fat soda straws from a fast food restaurant, cut them to lengths of about 4 inches, and insert them in your nose to breathe through. If you try to breathe through straws in your mouth you get a messed up facial expression.

Don't try to put the plaster on your own face. Get a helper. Lay on your back on some newspapers, as the plaster can be a bit messy. Start applying the plaster around the straws, being careful to not plug them, and then you can just ladle on more all around your face. A few sheets of cardboard will help you define the edges of the mold. Your assistant will have to position them for you, so go over this with them beforehand.

Ordinary plaster should get pleasantly warm, and be firm enough to remove in about 10 minutes. If you mix it and then let the stuff rest for 3-5 minutes you won't be under it for very long.

The flexibility of your skin and normal facial oils will keep the plaster from sticking to you, but if you want to put on a coat of oil, it won't hurt.

The cast of your face will be a female mold, which should be sufficient for making your mask. Sealing it with shellac, or some other lacquer (not varnish)is probably a good idea. So is paste wax.

Good luck with your project.

PGJ