Sedimentary rock question?

Question

A sedimentary rock such as the sandstone observed in the cliffs near Dawlish, UK contains well-sorted, well-rounded, fine pitted and reddened grains. What does this tell you about its origins?

Answer 1

It's probably an eolian (desert/dune) deposit...the sorting, rounding, and pitting tells you that. The grains contain some iron oxide (rust), so they weren't reworked long enough to alter diagenetically to quartz.

That's the most likely origin of the sandstone. The origin of the grains that make up the sandstone is another story altogether.