This article talks about the possibility of mining Uranium on the moon. Since the Moon lacks the geological forces that have created veins of concentrated minerals on Earth, would extraterrestrial mining be more difficult or impractical? How does Moon, Martian, or asteroid mining overcome the lack of mineral veins otherwise formed by Earth's geology?
It seems like extraterrestrial mining would be at least as difficult as trying to refine desert sand, which isn't a thing.
Wayfaring Stranger added an interesting link on ore genesis.