After the first attempt, I realized that groggy clay is very difficult to carve into and switched to using porcelain. The first step of the process is rolling out a slab of clay, then cutting out 12 pentagons and cutting the holes. I bevel and score the edges before building the dodecahedron. It helps to have a friend helping during the building process! I use slip to “glue” the sides together.
I love the contrast of black slip and the bright white color of the bare porcelain, so after the dodecahedron is built, I paint the entire piece with black slip (for a shinier finish I use SJ black, for a slate-like finish I use Conrad black, and a mix of the 2 will produce something in between). The white design is made by carving away the slip using a needle tool.
After the carving is finished, I put the piece in the bisque fire. After the bisque fire the clay is hard, making the piece less fragile, but no more carving can be done. I then glue small clay pads on the bottom (in a section that has been carved away exposing the bare clay), then fire the piece at Cone 10. The final piece is very shiny since I used SJ black. I didn’t like how shiny it turned out, so later pieces use a mix of the SJ and Conrad black for a more matte finish.