I would like to add, a perspective on value.

Let's take physical mining for example, there is cost of labour, machinery, renting or buying the lands, and probably a bunch of other costs. These all add up to create the bare minimum value of the (for example, iron) being mined. On top of that, for the efforts to be worth it, people have to add an extra cost to all processes of mining and even further if they are middle men for the goods being mined to be worth the time and effort to mine.

That'll be all.