Nice thought indeed MarlboroDog BUT if you brought a lot of gold down to earth not only the gold of the competition would be worth less but also yours, namely the cost that you put in to get it home would exceed your return.
There are rarer elements that we need and am not sure if it would be beneficial to bring them to earth in the near term.
The minerals in space are huge but they would for the most part remain in space. They would be used to produce macinery and structures in space. Moving them from one place to another while in space would be much cheeper and they would be very much needed there.
So hold that thought for the 22nd century. Now get back to today and quit dreaming, lol.