Testing different colour combinations and thicknesses of layers.
Rutile is my 'go to 'colour at the moment.
Again there are cracks. These would happen naturally in the landscape through weathering yet, for a piece to be shown in a gallery, I would prefer no cracks.
Sometimes they form along the strata lines and sometimes they appear across the layers.
A combination of drying thoroughly and layering sufficiently to remove air pockets needs to be undertaken.