I am experimenting with regular white bathroom tiles. Trying to figure out what kinds of paints or inks will work on them, permanently. So far, I don't think I know the trick or the secret. I really want to figure this out and do some lettering on them and make them into coasters. If anyone has any helpful hints, I'm all ears! Do I need to use acrylic paints, then put them in the oven to cure? Help me!