Noticing these features can help you. They can act as 'landmarks', so once you find a rare asteroid, you can use them to find it again. The features may also act as 'guide posts', with rare ore being concentrated around certain features or types of rock.
===Mineral Maps===
Once you find a nice rare ore, it might be helpful to write down where you found it. Here are some maps from those who have done exactly that:
[[mining:Mineral Maps]]
===Sources===