The area, which stretches from Nora over Riddarhyttan up to Avesta, has been named the REE line (Rare Earth Elements).

In the warp that was left behind after the old mines, you will now find rare earth metals that were not interesting when the mines were in operation.

Increased demand

But in the last 20 years, the demand for the metals has increased sharply.

Erik Jonsson is a state geologist at SGU, the Swedish Geological Survey, a state authority responsible for issues of rock, soil and groundwater.

They have investigated the REE line and according to Erik Jonsson, there are now several companies investigating the area's deposits.

- The problem is probably that it is an extremely dangerous metal industry to enter, he says.

- Because despite the fact that these metals are so critical in a number of products, they are still very small volumes.

Therefore, it may be enough for one or two new mines to open somewhere in the world for the market to change dramatically, which makes investors in new mines hesitate.