This is the plan(in bold the bonus chain):
Coal = Blaze of Macedon
Silver = Blaze of Macedon
Iron
Aluminum
Marble
Water = Gambit
Lumber
Wheat = Nagaichi
Wine = Nagaichi
Uranium = Gambit
Sugar = Kentlah
Gold = Kentlah
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Steel, Construction, Beer
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I know it's tough to have it all the best way so i'd be ready to make some reasonable compromises along the way to have a secure and longlasting trade circle.
Post if interested.