Changes

By the most new experiments (done at 20 skill in prospecting), it looks like the more distance the ore is, the more difficult its to determine what is.

A message like ''[xx:xx:xx] You notice a slight trace of something, but cannot quite make it out.'' would be shown then, as an example, for some ore in the 2nd tile radius, displaying the ore vein as unknown (even if the vein is exposed and you can see it).