It matters more where it hits and how big it is. If you want that material on Earth, it's best to break the rock apart in space in such a way that the chunks ar

It matters more where it hits and how big it is. If you want that material on Earth, it's best to break the rock apart in space in such a way that the chunks are still shielded from reentry heat, and send them on a good trajectory to crash somewhere empty and minable. Siberia and swathes of desert are a good choice.