>>32366663I... don't know. If we assume /ahoy/'s orogeny to be old, then its composition will depend on what said orogeny is, which is somewhat lacking given the information we have now. My guess is that the surface rocks of the highland will be a mix of hard igneous rocks (like granite) and metamorphic rocks that could withstand the weathering, with the gaps being filled by eroded sediments. The same weathering process also reduces the mineral deposits the hills have (as many of them are somewhat soluble, especially given /ahoy/'s warm and wet climate). Many of them will end up in the sea, but they can also pile up in the lowland alongside rivers old and new, so /ahoy/ would still have a decent amount of it if you know where to look.
Ultimately I would say just go with what you want and justify it backwards. You can probably expect the more common ones like iron and copper to be found with relative ease, but precious metals might be harder to find in biog deposits. Maybe that's one of the reasons why /ahoy/ becomes pirates?
