All the mountains of the world are either young (high mountains such as the Himalaya) or old (low mountains such as the Pyrenees mountains). The latter is a low mountain range because time has had its erosive effect.
There is no such thing as minerals going from one rock or mountain to the other because there is only one. And it´s young or (becomes) old.
You didnt provide the second sentence but from my understanding the prefix "un" , which means not, could be added to friendly to mean unfriendly or not friendly.
