A Mine is a tile improvement that can be built by Workers immediately upon the discovery of Mining. A mine adds 2 to its tile. Mines may be created on all hills, and on flatland tiles that have resources which are unlocked by mines.
When a Mine is worked, and it is not already on a resource tile, there is a small chance every turn that it will discover a new resource. A civ must have the tech unlocking a resource to gain it via a discovery.
- Gems, Gold and Silver can be unlocked from the start of the game.
- Copper requires Bronze Working.
- Iron requires Iron Working.
- Coal requires Steam Power.
- Uranium requires Physics.
- Aluminum requires Industrialism.
Resources that can be gained in this way are any of the resources unlocked by Mines: Aluminum, Coal, Copper, Gems, Gold, Iron, Silver, and Uranium.