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 2 Uranium Mines.
There are no National Projects that increase Uranium production. To increase Uranium Production, a nation must increase the number of Uranium Mines it has.
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.