Please share the info from the geologist about other color pigment.
Well, probably nothing that would be of too much use to anyone but us, I'm afraid, since it was all very specific to this area. But here goes. The big take-aways were:
1. The mustard-yellow rock is, in fact, yellow ocher. It is a fairly thin, intermediate layer in between other, more substantial layers.
2. Directly underneath this ocher sandstone layer we should find some clay stone or silt stone (we'll have to dig for it a bit) that should have interesting purple and green colors.
3. Anywhere we find belemnite fossils (also known as bullet fossils; quite common around here), look upslope for the rock shelf they've eroded from. It too should contain rocks of interesting colors: Blues, greens, grays, purples.