Interesting and rustic effects can be achieved by enameling over a clear transparent enamel. The clear transparent enamels are "soft" and the color you choose to put on top will sink into the clear layer a bit so the beautiful copper color shines through. Transparent enamel is also called flux not to be confused with the flux that is used in soldering. I use Thompsen medium clear and put a generous coat on the front and back. It's great for smaller pieces because it covers easily when fired and makes a good base for the next layer. For these pieces, I used Foundation white as my second layer and one layer of a transparent color on top. Pretty spring colors with a rustic look!