Follow this link to see the other posts concerning the Sea Urchin series.
This sea urchin is an EXTRA LARGE where as the first and third were small and the second was medium/large. I started with a 7" diameter 18g copper disk which was raised. I had to bring in the walls a bit or else it would not fit IN the pitch bowl. YES, IN IT. I removed most of the pitch from the bowl so I could literally get the shell into the bowl and then back fill around it. This allowed me to do all the repousse without having to remove and reposition it as I worked my way round the inside. I finished the chasing last weekend and then I had to raise the edge more to roll it under. I then applied a Liberty Green patina to give it that "long under the sea" look.
Enjoy the process pictures.