Test for sheet of plaster with varied layers

Today I've made a test mould for a plaster sheet. I want to create a sheet with layers in multiple directions, so the mould needs to be detachable from all sides. I will pour one layer and then prop the mould one way. I will then rotate the mould and open a different side before pouring a different coloured plaster into the mould. Describing this is extremely difficult, so here are some photos!