[UB] Treasury (replaces Mint): Can be built everywhere. Also provides +2 Gold from Salt. When constructed, reveals a new source of Copper, Silver, Gold, or Salt on an appropriate unimproved tile within the City's borders (if possible).
Known Issue: The UU and UB borrow art from other parts of the game.
Treasury probabilities: Desert = (Gold 40%, Salt 30%, Copper 20%, Silver 10%). Grassland = (Gold 45%, Salt 11%, Copper 33%, Silver 11%). Plains = (Gold 33%, Salt 33%, Copper 22%, Silver 12%). Tundra = (Gold 25%, Salt 25%, Copper 25%, Silver 25%). Hills override flat tiles with the following ratios: (Gold 50%, Salt 0%, Copper 25%, Silver 25%)
[BUG]: Hill override mentioned above does not currently work - it treats the tile as if it were not a hill and bases the chance on the terrain only, allowing Salt hills.