Asteroids are clumps of rocks and ices. So where are all the rocks?
This mod changes regular and advanced asteroid processing to return 5 (configurable) stone instead of the asteroid you fed into in. Although this might be more lore friendly, there's a better reason why to use this mod. Stone is the only basic raw mineral resource that can't be mined on aquilo or dropped down from space without first sending it ... up to space. Putting rocks into rockets, flying across the solar system, just to drop rocks down onto aquilo for some train track seems a bit, brute forcey.
Now, you can keep some stone, throw the rest overboard and make Aquilo fully self sufficient.