Minecraft wiki entry for Mining, associated text: Really reckless miners have been known to make huge quarries, some giant ones are 50×50, 64×64 and 80×80, yielding a staggering 2200 stacks of cobblestone/stone. To put that in perspective, that many cobblestone blocks in a tower would be a whopping 140,800 meters tall, or an unrealistic 170 times the height of the Burj Khalifa, which is the tallest building on earth. These will take a couple weeks of 24/7 gameplay, given their size, but the stone payoff is gigantic.