[1.0.1.383] Hot Seat - Mt. Fuji lost its culture

[HappyBuilder]

I founded a city next to Mt. Fuji so I could work it for culture. At some point during the game, it stopped producing it. All it gives me now is 2 gold per turn. Unfortunately, I wasn't micromanaging and didn't take note of when the culture disappeared. I suspect it happened at one of the save points. When the game reloaded, the culture was gone. Anyone else have an issue with a natural wonder? Can you exhaust a national wonder?

HB