Limits to cities of a given resource in Antike Duellum?

Question

In a current game on Yucata.de (http://www.yucata.de/en/Game/CasusBelli/4606422), both my opponent and I have tried to build gold producing cities and failed. We have a total of 10 gold cities on the board, which doesn't seem like it would trigger a limit and we can't find anything about it in the rules (http://www.yucata.de/en/Rules/CasusBelli). Is there a limit to the cities you can found to produce each resource?

The rules on Yucata state that when founding a city: "The player takes a city token out of the bank’s supply (marble, iron, or gold), and puts it at the place of the newly founded city on the board." It doesn't say anything about limits on these city tokens.

Answer 1

The Yucata rules state (emphasis mine)

The game material comes in limited quantity. If a player has no more legions or galleys, or if the bank has no more city tokens or temples, the supply is empty. Only resource chips are unlimited.

24 galleys (12 per player color brown and beige)

24 legions (12 per player color brown and beige)

12 temples (white)

10 gold-cities

12 marble-cities

12 iron-cities

12 Town Walls

Answer 2

There are 10 Gold cities, 12 Marble and 12 Iron cities in the physical game. These tiles are all double sided to mark which player owns them. So 10 Gold cities is the maximum limit.