What are mountains made of?

I noticed that mountains have a gray, stone-ish color. Does digging these areas still yield dirt? Or are there plans to make stone blocks from them? For that matter, does digging snow give dirt too?

Of course to make it natural the surface should be covered some dirt and under the dirt full of Rocks with some ores ofc to mine! With oil too like in BH

I’m not sure yet how I’ll deal with mining different surface types, or how ores will be found. For now they just look different to make it look more interesting, and that’s it. But I do definitely plan to add ores, and yep it’ll probably make sense to get rock when you mine rock!