The original project was published in my first book, pp 15-17. In this version the earrings are flat, not concave.
1. Start with a copper circle as the back layer.
2. Follow steps 3 – 6 of the original project, using smooth layers of bronze and copper clay instead of textured layers of silver clay.
Watch the circles as they dry. As soon as they start warping, flip them over. Repeat until they stop warping. Alternatively you can tape them to a Corian block or a piece of sheet metal.
3. Instead of steps 7 – 8 of the original project, roll a layer of bronze clay. Lay a snake of copper clay on it and roll it down, as in the project “Necklace/Bracelet with Bronze and Copper Clay,” published here on this blog.
Cut the small circle out of the layer.
4. Fire the earrings. Finish them as described in Part 2 of the project above.
Here is the design suggested on p. 16:
And here is the one suggested on p. 17: