So I've just heard in Oathbringer > 60. 'Winds and Oaths' where Kaladin observes the colorful strata of the Windblades. I've heard this at least once before as well. And searching through other forum topics - it seems like other unique stone formations on Roshar may have similar. Question is: why are these not covered over with millennia-worth of crem by now? How are external rock-faces exhibiting colorful strata at all? Any ideas?