Create 20cm square (or with lip 26cm square) dishes easily.
This mold actually has a total size of 26cm square, with the inner slump an 20cm square. The inner bottom flat is approximately 12cm square with a depth of 1.5cm.
You can trim the clay to the 20cm square, or add a "lip" to your dish and trim at the 26cm square. Allow clay slab to dry in the mold before removing from mold and firing.
Plaster mold for use with clay only.