Days of Evil - Official Board

So how can you produce Cobalt?

Finally built my Foundry, its description says it can produce Cobalt.

But when I press "Commission", there is no Foundry option to produce Cobalt?

You need to expand your Foundry from small to middle to produce cobalt.
To do so, go to Production / Expand Buildings and before issuing the command make sure you have no tasks running in the Foundry and that you have the necessary resources:

The following products are needed to expand the building:
35.000 Gold, 22.000 Wood, 95.000 Stones, 150.000 Water, 100 Steel
Duration:: 34 Hours 43 Minutes 20 Seconds

Cheers,
st0rm

Wow, many thanks for your very quick and helpful reply!!