I simply cannot beleive the math!
A Gold Ore mine contains 300 ore and costs 1400 Hardwood, 1400 Marble and 1500 Tools - per mine!
To smelt Ore into gold bars you need 2 Ore and 8 Coal to produce just One Gold Bar. Four Gold bars produce One coin!
A Gold Ore mine therefore produces no more than 75 coins! With the additional cost of 2400 coal used in the production of the Gold bars! (I'm also writing off for 'free' the 4500 Hardwood 4500 Marble and 5500 Tools used as a one off cost to build the Gold Smelter and Coinage building in the first place!)
I am sure anyone will realise they could produce:
1400 Hardwood,
1400 Marble
1500 Tools
2400 Coal
and trade the lot for far more than 75 Gold Coins! (I just traded 400 Coal for 35 coins!)
So what is the point of this production system or using it to produce gold goins?
Sorry I don't get it!