Really nice concept, I enjoyed a lot looking around and finding where to get the upgrades :)
I noticed that if you spam E when you are on top of ore, and then let the animation finish, then press again E, you can get essentially as much as you want (instead of a single one). I don't know if that's intended n.n" Also, the "Back" button in the settings was not always responding, but it worked after some tries.
Apart from that, very well done! 3D feels so daunting to me :O