Earth may be a finite source of minerals, but there's always outer space. That's one of the thoughts behind a project Chinese scientists have recently proposed. A paper published in the Chinese Journal of Astronomy and Astrophysics hypothesizes that an asteroid could be temporarily captured in Earth's orbit, making it possible to mine it for valuable minerals.
The paper is based on the observation that Jupiter occasionally has trapped passing objects in its orbit temporarily, only to release them again on a new course. The scientists have targeted a 10-meter asteroid as a possible test candidate and speculate that a slight increase in its velocity would cause it to temporarily enter Earth's orbit at a distance about twice the distance of the moon.
There are no plans to mine the small test asteroid, but the scientists do propose studying it once captured. Once the technique of pulling objects into Earth's orbit is mastered, then the idea of asteroid mining could fully be considered. Asteroid mining isn't a new idea. You can read more about it here. You can also see more coverage of these scientists' work in Popular Science and Technology Review.