Rock Dust

So in Minecraft you get raw iron/copper/gold after mining an ore, but what happens to the rest of it? What I suggest is that when you mine an ore you get 1-2 of rock dust. What you can do is put 4 of them in a crafting bench or your inventory crafting and make 1 piece of cobblestone. You can also get 4 pieces of rock dust after dropping an anvil on top of a block of cobble or stone.