I've been looking into some rumors and a theory of mine. I've found that the different colors of rock on grassy tiles seem to indicate the type of ore in the vicinity. I've found copper near greenish rocks and iron near the large gray rocks. It should be noted that greenish rocks were not present where I found iron and visa virsa. I'm still looking into this and would love more information regarding this subject to the degree it could be added to this page.
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