Board Thread:General Mod Discussion/@comment-30303386-20180208063501/@comment-33185350-20180215045228

Recneps wrote: It almost definitely had fertile soil with its name being the Green Hills. I suppose it could just have lots of copper in the soil/rocks, but I think it's more likely it was fairly fertile.

Yeah. In real life copper ore looks nothing like the mod’s idealized version - I have actually found pieces of copper ore. But I agree the description is more likely due to vegetation. Fertile soil and at least a decent amount of rain would explain it.