Stone-specific caves

With the recent announcement of the Caves&Cliffs update, I had the idea to have stone-specific caves. For example, there would be a granite cave, an andesite cave, a cobble/gravel cave or (sorry Iskall) a diorite cave. Maybe we could introduce some other stone types as well, but that is for another suggestion. The caves could also have their own features as well. Maybe andesite caves can only be found just below the surface like often in real life.