Mantle convection is a process of that creates circular currents in the asthenosphere. As a result, the
plates slowly move.

Dis the answer you perception is how you see the world 

Where's the we need to see the it could be any country!

If a particular resource is not useful or needed then the price would be considerably low. once that resource is needed the price or value will raise depending on how useful or needed it is especially if the resource is low in quantity, the consumers would pay whatever they have to, to get that material.

The bottom part thats where most farming goes on