This artwork is called ‘What will be left’
All currently awarded mining licences were cut out from a tourist map, to make the actual impact visible. Not all licenses will be used immediately or at all, but companies would not pay for such licenses if they did not have the intention of using it sooner or later. Also many of the areas are awarded more than once, for instance for diamonds and for nuclear fuels at the same time.
(This information can be found on the webpage of the Ministry of Mines & Energy of Namibia).