I've been experimenting a bit this last week with glass paint (Porcelain 150). It is a bake on paint and I already had some. The recommended temperature is 300F for 35 minutes and the polymer clay is for 275F. No problem cooking even thin pieces for that length and the paint does bond at that temperature. But it's semi-reliable.
For one thing the paint has to be completely dry. A thick coating takes about a week and could be longer. The clear glaze has a slight yellow tint to it. Some colors work better than other colors and some come out more matte than others. The transparent colors show brush marks. You can't touch the surface until it is totally cooled down or it will dull.
But it works great on a metallic piece as a gloss (gives it more of a glasslike look that acrylic glazes) and it's very neat for tiny dot embellishments. I did a test piece of black dots (use the end of a tiny detail brush...it will not flatten out or run in the baking process) on pearl white and it was almost hypnotizing to see the shiny dots against the matte pearl when it moves. But I touched that before it was totally cool and lost the shine (impatience gets you every time). I reproduced the look with white on red (see below) and it worked well, but the white absorbs light rather than reflect it. So, the paint is useable with polymer clay, but be aware that you never can be 100% sure of the results.
So this piece is a total concept piece, inspired by a painting of poisonous mushrooms I did long ago. I wanted to not be literal and not just sculpt a whole mushroom, so I played with the repeating shape of the mushroom head, nestling the 3 little heads on top of a rounded piece and then cupping the whole thing inside a larger inverted mushroom head shape. I also knew I was going to try the raised dot thing, so I wanted to contrast that with an opposite texture (pierced holes)...this is the result...
It's just about an inch around. When I did the black on white spots in my experiment I got perfect little round dots, but I used a much thicker paint for this, sacrificing the perfect spheres so that I wouldn't be taking the chance of running paint. But I like that I acheived what I was aiming for, I'm wearing it right now and loved the feel of the raised surface. The shapes remind me of several things...one is baby cactus and the other is little strawberries (and I won't say the other things it makes me think of lol). The very matte pitted black piece looks like volcanic rock and is a nice contrast. Maybe the design is a little out there (like having a koi pond on your chest lol) but concept art isn't about the norm, it's about pushig the boudaries of a conceptual idea.
I like the idea of taking a known object and abstracting it, but it's not always successful (even as a concept)...I did a monstrosity of a piece today that went straight from oven to trash :D (well, not really...the colors are neat, but the design was too bulky for a pendant and didn't want to stay in the right position, but it may look neat as a little windcatcher, so I hung on to it)
I also played with getting something that looked like an antique coin and put a clear glass paint finish on that...in this case I used a carved vase design as a 'stamp' and then distressed it.
The finish doesn't show in the photo, only in strong light...which I find unusual because my acrylic varnish glares in any light.
Anyways, nothing earth shattering for results, but I had a lot of fun doing the experiments. Hope you enjoyed too :)