For the colored lithophanes, we take the process one step further. We hand apply  ceramic pigments to the back of the porcelain panel, and then fire the panel in our kilns at 1300 degrees F, to permanently fuse the color to the porcelain. Is this a more difficult method? Yes. We could have gone the easy way, using acrylic paint that can eventually fade or peel off. But our lithophanes are designed to be cherished heirlooms, and not just a momentary whim.