Uranium is a Continent specific resource, only available to some nations. Nations in North America, Asia, and Africa have the ability to build Uranium Mines in their cities to produce Uranium.
Uranium Mines produce 0.25 Uranium per turn each, accumulating to 3 Uranium per day. Uranium Mines are expensive to build and operate, and never run out of Uranium to mine. Each city can have up to 5 Uranium Mines.
The Uranium Enrichment Program National Project doubles Uranium production. To increase Uranium Production, a nation must increase the number of Uranium Mines it has or build the Uranium Enrichment Program.
Uranium is used to fuel Nuclear Power Plants which are a high-end Power Improvement for large nations. Uranium is also necessary for building Nuclear Weapons, the most devastating weapons in the game. Uranium is very scarce, and primarily imported by very large nations.