Bug: Conquests Multiplayer (regular deathmatch game--not a scenario) - Settled on top of a saltpeter source. When you right-click to get Terrain Info, it indicates that it is Saltpeter; however, when you go to the Trade screen (F2), the resource appears as horses. This prevented me from getting musketmen at any point in the game.

JBAdams101, Here (http://forums.civfanatics.com/showthread.php?s=&threadid=55122) are instructions on how to upload saves. It would probably be helpful if you uploaded a game save where this happened. And even if it isn't helpful then the rest of us will have fun seeing the situation ourselves.

might be similar to this bug:

look at this post (http://forums.civfanatics.com/showthread.php?s=&threadid=68696)