To give you a little more information most of the resource do not have hard rules. That is to say that gold is most common at low altitudes but can spawn at higher ones on rare occasions.
Additionally gems will only be able to be found on their own world types e.i. ruby on burn worlds. We are making a small change though. You will be able to find gem types of the worlds sister element just in much lower quantities e.i. a low amount of diamond on burn world.