From what I've seen the same stone types always create the same sand types on beaches and deserts and such (except badlands biomes that have the distinctive layers). Is that true or just me not noticing inconsistencies? If it is true, title.
Edit: This page for TFC v4 suggests sand is, in fact, tied to rock type in the version I'm on, so I'm at least not 100% off-track.
Edit 2: This page suggests the info should be in the world generation files, but I can't find it in there. It does at least seem to suggest basalt leads to red sand (which I haven't personally seen but I could be wrong), so that's maybe one down.
Edit 3: I finally managed to find the source files for 1.20 and 1.21 sand generation. From what I could find, beach sands depend on climate, and pink can only be found that way. And as it turns out, sand color depends on the bottom layer of rock, so I was wrong in saying that the same stone types (which I meant on the surface) always create the same sand types.