I also want to know if you can farm ores. Sorry, I‘m a newbie.
They are limited, however the world size is so large, that they can be considered ininite. In fact the minecraft world is 64000km x 64000km. Unfortunately without mods it is not possible to farm ores.
Ores will not respawn, but since Minecraft generates new chunks (small sections of the world) when you go to unexplored areas, you'll never run out. It's an endless world. If you ever run out of ore, just wander off, and you'll be able to find more. So the ore is unlimited, really.
the ores don't respawn. most of the blocks dont respawn. but the world is INFINITE ^_^ explore to your hearts content. there are so many caves and tunnels i've been playing for over a year and the world generator still amazes me.
