Filling in negative spaces and surrounding the object with clay:
The clay at the bottom is a drain for when the mold is used with clay slip (liquid clay). The four round lumps of clay are "keys," where the top part of the mold will fit into the bottom.
Everything is wiped down with soap to keep it from sticking to the plaster.
The pottery plaster is poured on top.
After it dries, it is turned over.
Here I am preparing to make the other side of the mold.
I think I used the wrong type of soap or not enough of it because the plaster stuck to the bottom part of the mold and it was only with a great deal of pounding and cursing that I was able to extract and rescue the Cat Head. The molds were destroyed in the process.
