How do I mine gems and how do I build?

I have completed the first part of the game and I am now in the last cell of the map, where you can continue to the world map. I have explored around 98% and scouted 100%. I also killed the Boss where you are told to turn around after finding new Spells. Then I found the settlement.

My question is:

How can I get those colored gems in the dungeons and how exactly do I build? I am a bit confused about that atm :). Thanks for any answer.

Solution 1:

Use one of the touch spells (like Fire Touch spell you get first off) on the gem vein as if it was a monster you wanted to kill.

Paraphrasing from the arcengames wiki: Building requires a guardian power scroll for the particular building and an NPC with a particular profession and enough skill in said profession