Burner mining drill
Mines about 7 resources per single unit of coal used to fuel it. Covers and mines in a 2x2 area. Mines 0.28/s of copper, coal or iron and .3675/s of stone. Burner miners create a lot of pollution per resource.
Two burner mining drills can refuel each other, when placed next to each other on a coal deposit as long as they're facing each other. Each drill fuels the other and coal gradually accumulates in their Storage/Stacks, so you have effectively a storage of 100 coal (2 stack, 50 coal, one in each burner miner, together 100). You can do this also for 4 or any other even number of miners, though Electric Mining Drills are far more efficient once Electricity is available.